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Sun Q, Hao Y, Liu Y, Cui M, Zhang G, Yu W, Luo L. Identification and Characterization of Polyamine Metabolism in Citrus in Response to ' Candidatus Liberibacter asiaticus' Infection. PHYTOPATHOLOGY 2024; 114:1380-1392. [PMID: 38349804 DOI: 10.1094/phyto-04-23-0114-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Citrus Huanglongbing, one of the most devastating citrus diseases, is caused by 'Candidatus Liberibacter asiaticus' (CLas). Polyamines are aliphatic nitrogen-containing compounds that play important roles in disease resistance and are synthesized primarily by two pathways: an arginine decarboxylation pathway and an ornithine decarboxylation pathway. However, it is unclear whether polyamines play a role in the tolerance of citrus to infection by CLas and, if so, whether one or both of the core polyamine metabolic pathways are important. We used high-performance liquid chromatography and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry to detect the contents of nine polyamine metabolism-related compounds in six citrus cultivars with varying levels of tolerance to CLas. We also systematically detected the changes in polyamine metabolism-related compounds and H2O2 contents and compared the gene expression levels and the activities of enzymes involved in the polyamine metabolic pathway among healthy, asymptomatic, and symptomatic leaves of Newhall navel oranges infected with CLas. The tolerant and moderately tolerant varieties showed higher polyamine metabolism-related compound levels than those of susceptible varieties. Compared with the healthy group, the symptomatic group showed significantly increased contents of arginine, ornithine, γ-aminobutyric acid, and putrescine by approximately 180, 19, 1.5, and 0.2 times, respectively, and upregulated expression of biosynthetic genes. Arginase and ornithine decarboxylase enzyme activities were the highest in the symptomatic group, whereas arginine decarboxylase and agmatine deiminase enzyme activities were the highest in the asymptomatic group. The two polyamine biosynthetic pathways showed different trends with the increase of the CLas titer, indicating that polyamines were mainly synthesized through the arginine decarboxylase pathway in the asymptomatic leaves and were synthesized via the ornithine decarboxylase pathway in symptomatic leaves. These findings provide new insight into the changes in polyamine metabolism in citrus infected with CLas.
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Affiliation(s)
- Qifang Sun
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang 330047, China
| | - Yingbin Hao
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Yongquan Liu
- College of Life Sciences, Gannan Normal University, Ganzhou 341000, China
| | - Meng Cui
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Gaowei Zhang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Wenjie Yu
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Liping Luo
- School of Food and Health, Beijing Technology and Business University, Beijing 100048, China
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Wang M, Chen Y, Li S, Yu J, Yang L, Hong L. Widely Targeted Metabolomic Analysis Provides New Insights into the Effect of Rootstocks on Citrus Fruit Quality. Metabolites 2024; 14:242. [PMID: 38668370 PMCID: PMC11052146 DOI: 10.3390/metabo14040242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
The use of different rootstocks has a significant effect on the content of flavor components and overall fruit quality. However, little information is available about the metabolic basis of the nutritional value of citrus plants. In this study, UPLC-MS/MS (ultra-performance liquid chromatography-tandem mass spectrometry) was performed to analyze the metabolites of three late-maturing hybrid mandarin varieties ('Gold Nugget', 'Tango' and 'Orah') grafted on four rootstocks ('Trifoliate orange', 'Carrizo citrange', 'Red tangerine' and 'Ziyang Xiangcheng'). A total of 1006 metabolites were identified through OPLS-DA (Orthogonal Partial Least Squares-Discriminant Analysis) analysis. KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis revealed the most critical pathways among the different pathways associated with genes grafted on the four rootstocks that were differentially activated, including tryptophan metabolism and sphingolipid metabolism in 'Gold Nugget'; tryptophan metabolism, phenylpropanoid biosynthesis and sphingolipid metabolism in 'Tango'; and pantothenate and CoA biosynthesis- and photosynthesis-related biosynthesis in 'Orah'. A considerable difference between the different rootstocks was also observed in the accumulation of lipids, phenolic acids and flavonoids; further analysis revealed that the rootstocks regulated specific metabolites, including deacetylnomylinic acid, sudachinoid A, amoenin evodol, rutaevin, cyclo (phenylalanine-glutamic acid), cyclo (proline-phenylalanine), 2-hydroxyisocaproic acid, and 2-hydroxy-3-phenylpropanoic acid. The results of this study provide a useful foundation for further investigation of rootstock selection for late-maturation hybrid mandarin varieties.
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Affiliation(s)
- Min Wang
- Fruit Tree Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China; (M.W.); (S.L.); (J.Y.)
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
| | - Yang Chen
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
- Biotechnology Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China
| | - Shuang Li
- Fruit Tree Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China; (M.W.); (S.L.); (J.Y.)
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
| | - Jianjun Yu
- Fruit Tree Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China; (M.W.); (S.L.); (J.Y.)
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
| | - Lei Yang
- Fruit Tree Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China; (M.W.); (S.L.); (J.Y.)
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
| | - Lin Hong
- Fruit Tree Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China; (M.W.); (S.L.); (J.Y.)
- Key Laboratory of Evaluation and Utilization for Special Crops Germplasm Resource in the Southwest Mountains, Ministry of Agriculture and Rural Affairs, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China;
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Li Y, Ma R, Gao C, Li Z, Zheng Y, Fang F, Wang C, Li G, Du X, Xu C, Xu M, Liu R, Deng X, Zheng Z. Integrated bacterial transcriptome and host metabolome analysis reveals insights into " Candidatus Liberibacter asiaticus" population dynamics in the fruit pith of three citrus cultivars with different tolerance. Microbiol Spectr 2024; 12:e0405223. [PMID: 38440971 PMCID: PMC10986616 DOI: 10.1128/spectrum.04052-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 01/22/2024] [Indexed: 03/06/2024] Open
Abstract
"Candidatus Liberibacter asiaticus" (CLas), the causal agent of citrus Huanglongbing (HLB), is able to multiply to a high abundance in citrus fruit pith. However, little is known about the biological processes and phytochemical substances that are vital for CLas colonization and growth in fruit pith. In this study, CLas-infected fruit pith of three citrus cultivars ("Shatangju" mandarin, "Guanxi" pomelo, and "Shatian" pomelo) exhibiting different tolerance to CLas were collected and used for dual RNA-Seq and untargeted metabolome analysis. Comparative transcriptome analysis found that the activation of the CLas noncyclic TCA pathway and pathogenic-related effectors could contribute to the colonization and growth of CLas in fruit pith. The pre-established Type 2 prophage in the CLas genome and the induction of its CRISPR/cas system could enhance the phage resistance of CLas and, in turn, facilitate CLas population growth in fruit pith. CLas infection caused the accumulation of amino acids that were correlated with tolerance to CLas. The accumulation of most sugars and organic acids in CLas-infected fruit pith, which could be due to the phloem blockage caused by CLas infection, was thought to be beneficial for CLas growth in localized phloem tissue. The higher levels of flavonoids and terpenoids in the fruit pith of CLas-tolerant cultivars, particularly those known for their antimicrobial properties, could hinder the growth of CLas. This study advances our understanding of CLas multiplication in fruit pith and offers novel insight into metabolites that could be responsible for tolerance to CLas or essential to CLas population growth.IMPORTANCECitrus Huanglongbing (HLB, also called citrus greening disease) is a highly destructive disease currently threatening citrus production worldwide. HLB is caused by an unculturable bacterial pathogen, "Candidatus Liberibacter asiaticus" (CLas). However, the mechanism of CLas colonization and growth in citrus hosts is poorly understood. In this study, we utilized the fruit pith tissue, which was able to maintain the CLas at a high abundance, as the materials for dual RNA-Seq and untargeted metabolome analysis, aiming to reveal the biological processes and phytochemical substances that are vital for CLas colonization and growth. We provided a genome-wide CLas transcriptome landscape in the fruit pith of three citrus cultivars with different tolerance and identified the important genes/pathways that contribute to CLas colonization and growth in the fruit pith. Metabolome profiling identified the key metabolites, which were mainly affected by CLas infection and influenced the population dynamic of CLas in fruit pith.
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Affiliation(s)
- Yun Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Ruifeng Ma
- Institute of Fruit Tree Research, Meizhou Academy of Agriculture and Forestry Sciences, Meizhou, Guangdong, China
| | - Chenying Gao
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Ziyi Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Yongqin Zheng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Fang Fang
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Cheng Wang
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Guohua Li
- Institute of Fruit Tree Research, Meizhou Academy of Agriculture and Forestry Sciences, Meizhou, Guangdong, China
| | - Xiaozhen Du
- Institute of Fruit Tree Research, Meizhou Academy of Agriculture and Forestry Sciences, Meizhou, Guangdong, China
| | - Changbao Xu
- College of Horticulture, South China Agricultural University, Guangzhou, Guangdong, China
| | - Meirong Xu
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Rui Liu
- Institute of Fruit Tree Research, Meizhou Academy of Agriculture and Forestry Sciences, Meizhou, Guangdong, China
| | - Xiaoling Deng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Zheng Zheng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
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Castellano-Hinojosa A, Albrecht U, Strauss SL. Interactions between rootstocks and compost influence the active rhizosphere bacterial communities in citrus. MICROBIOME 2023; 11:79. [PMID: 37076924 PMCID: PMC10116748 DOI: 10.1186/s40168-023-01524-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 03/20/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND While the rootstock genotype (belowground part of a plant) can impact rhizosphere microbial communities, few studies have examined the relationships between rootstock genotype-based recruitment of active rhizosphere bacterial communities and the availability of root nutrients for plant uptake. Rootstocks are developed to provide resistance to disease or tolerance of abiotic stresses, and compost application is a common practice to also control biotic and abiotic stresses in crops. In this field study, we examined: (i) the effect of four citrus rootstocks and/or compost application on the abundance, diversity, composition, and predicted functionality of active rhizosphere bacterial communities, and (ii) the relationships between active rhizosphere bacterial communities and root nutrient concentrations, with identification of bacterial taxa significantly correlated with changes in root nutrients in the rhizosphere. RESULTS The rootstock genotype determined differences in the diversity of active rhizosphere bacterial communities and also impacted how compost altered the abundance, diversity, composition, and predicted functions of these active communities. Variations in the active bacterial rhizobiome were strongly linked to root nutrient cycling, and these interactions were root-nutrient- and rootstock-specific. Direct positive relationships between enriched taxa in treated soils and specific root nutrients were detected, and potentially important taxa for root nutrient uptake were identified. Significant differences in specific predicted functions were related to soil nutrient cycling (carbon, nitrogen, and tryptophan metabolisms) in the active bacterial rhizobiome among rootstocks, particularly in soils treated with compost. CONCLUSIONS This study illustrates that interactions between citrus rootstocks and compost can influence active rhizosphere bacterial communities, which impact root nutrient concentrations. In particular, the response of the rhizobiome bacterial abundance, diversity, and community composition to compost was determined by the rootstock. Specific bacterial taxa therefore appear to be driving changes in root nutrient concentrations in the active rhizobiome of different citrus rootstocks. Several potential functions of active bacterial rhizobiomes recruited by different citrus rootstocks did not appear to be redundant but rather rootstock-specific. Together, these findings have important agronomic implications as they indicate the potential for agricultural production systems to maximize benefits from rhizobiomes through the choice of selected rootstocks and the application of compost. Video Abstract.
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Affiliation(s)
- Antonio Castellano-Hinojosa
- Department of Soil, Water, and Ecosystem Sciences, Southwest Florida Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 2685 State Rd 29N, Immokalee, FL, 34142, USA.
| | - Ute Albrecht
- Department of Horticultural Sciences, Southwest Florida Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 2685 State Rd 29N, Immokalee, FL, 34142, USA
| | - Sarah L Strauss
- Department of Soil, Water, and Ecosystem Sciences, Southwest Florida Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, 2685 State Rd 29N, Immokalee, FL, 34142, USA.
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Chen Q, Min A, Luo S, He J, Wu R, Lin X, Wang Y, He W, Zhang Y, Lin Y, Li M, Zhang Y, Luo Y, Tang H, Wang X. Metabolomic Analysis Revealed Distinct Physiological Responses of Leaves and Roots to Huanglongbing in a Citrus Rootstock. Int J Mol Sci 2022; 23:ijms23169242. [PMID: 36012507 PMCID: PMC9409271 DOI: 10.3390/ijms23169242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 12/11/2022] Open
Abstract
Huanglongbing (HLB) is an obstinate disease in the citrus industry. No resistant citrus resources were currently available, but various degrees of Huanglongbing tolerance exist in different germplasm. Citrus junos is emerging as one of the popular rootstocks widely used in the citrus production. However, its responses to the HLB causal agent, Candidatus Liberibacter asiaticus (CLas), were still elusive. In the current study, we investigated the physiological, anatomical, and metabolomic responses of a C. junos rootstock ‘Pujiang Xiangcheng’ by a controlled CLas grafting inoculation. The summer flushes and roots were impaired at 15 weeks after inoculation, although typical leaf symptomatic phenotypes were not obvious. The chlorophyll pigments and the photosynthetic rate were compromised. The phloem sieve tubes were still working, despite the fact that the callose was deposited and the starch granules were accumulated in the phloem cells. A wide, targeted metabolomic analysis was carried out to explore the systematic alterations of the metabolites at this early stage of infection in the leaves and root system. The differentially accumulated metabolites in the CLas-affected leaves and roots compared with the mock-inoculation control tissues revealed that distinct responses were obvious. Besides the commonly observed alteration of sugar and amino acids, the active break down of starch in the roots was discovered. The different types of fatty acids were altered in the two tissues, with a more pronounced content decline in the roots. Our results not only provided fundamental knowledge about the response of the C. junos rootstock to the HLB disease, but also presented new insights into the host–pathogen interaction in the early stages.
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Affiliation(s)
- Qing Chen
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Ailing Min
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Shu Luo
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Jinwei He
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Runqin Wu
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Ximeng Lin
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Yan Wang
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
| | - Wen He
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
| | - Yunting Zhang
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
| | - Yuanxiu Lin
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
| | - Mengyao Li
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Yong Zhang
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Ya Luo
- College of Horticulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Haoru Tang
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
- Correspondence: (H.T.); (X.W.)
| | - Xiaorong Wang
- Institute of Pomology and Olericulture, Sichuan Agricultural Universtiy, Chengdu 611130, China
- Correspondence: (H.T.); (X.W.)
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Mashabela MD, Masamba P, Kappo AP. Metabolomics and Chemoinformatics in Agricultural Biotechnology Research: Complementary Probes in Unravelling New Metabolites for Crop Improvement. BIOLOGY 2022; 11:1156. [PMID: 36009783 PMCID: PMC9405339 DOI: 10.3390/biology11081156] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/16/2022] [Accepted: 07/28/2022] [Indexed: 11/25/2022]
Abstract
The United Nations (UN) estimate that the global population will reach 10 billion people by 2050. These projections have placed the agroeconomic industry under immense pressure to meet the growing demand for food and maintain global food security. However, factors associated with climate variability and the emergence of virulent plant pathogens and pests pose a considerable threat to meeting these demands. Advanced crop improvement strategies are required to circumvent the deleterious effects of biotic and abiotic stress and improve yields. Metabolomics is an emerging field in the omics pipeline and systems biology concerned with the quantitative and qualitative analysis of metabolites from a biological specimen under specified conditions. In the past few decades, metabolomics techniques have been extensively used to decipher and describe the metabolic networks associated with plant growth and development and the response and adaptation to biotic and abiotic stress. In recent years, metabolomics technologies, particularly plant metabolomics, have expanded to screening metabolic biomarkers for enhanced performance in yield and stress tolerance for metabolomics-assisted breeding. This review explores the recent advances in the application of metabolomics in agricultural biotechnology for biomarker discovery and the identification of new metabolites for crop improvement. We describe the basic plant metabolomics workflow, the essential analytical techniques, and the power of these combined analytical techniques with chemometrics and chemoinformatics tools. Furthermore, there are mentions of integrated omics systems for metabolomics-assisted breeding and of current applications.
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Affiliation(s)
| | | | - Abidemi Paul Kappo
- Department of Biochemistry, Faculty of Science, University of Johannesburg, Auckland Park Kingsway Campus, P.O. Box 524, Johannesburg 2006, South Africa; (M.D.M.); (P.M.)
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Ali Q, Zheng H, Rao MJ, Ali M, Hussain A, Saleem MH, Nehela Y, Sohail MA, Ahmed AM, Kubar KA, Ali S, Usman K, Manghwar H, Zhou L. Advances, limitations, and prospects of biosensing technology for detecting phytopathogenic bacteria. CHEMOSPHERE 2022; 296:133773. [PMID: 35114264 DOI: 10.1016/j.chemosphere.2022.133773] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 01/23/2022] [Accepted: 01/25/2022] [Indexed: 05/22/2023]
Abstract
Phytopathogenic bacteria cause severe economic losses in agricultural production worldwide. The spread rates, severity, and emerging plant bacterial diseases have become serious threat to the sustainability of food sources and the fruit industry. Detection and diagnosis of plant diseases are imperative in order to manage plant diseases in field conditions, greenhouses, and food storage conditions as well as to maximize agricultural productivity and sustainability. To date, various techniques including, serological, observation-based, and molecular methods have been employed for plant disease detection. These methods are sensitive and specific for genetic identification of bacteria. However, these methods are specific for genetic identification of bacteria. Currently, the innovative biosensor-based disease detection technique is an attractive and promising alternative. A biosensor system involves biological recognition and transducer active receptors based on sensors used in plant-bacteria diagnosis. This system has been broadly used for the rapid diagnosis of plant bacterial pathogens. In the present review, we have discussed the conventional methods of bacterial-disease detection, however, the present review mainly focuses on the applications of different biosensor-based techniques along with point-of-care (POC), robotics, and cell phone-based systems. In addition, we have also discussed the challenges and limitations of these techniques.
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Affiliation(s)
- Qurban Ali
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China; Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing, 210095, China.
| | - Hongxia Zheng
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Muhammad Junaid Rao
- Guangxi Key Laboratory of Sugarcane Biology, College of Agriculture, Guangxi University, 100 Daxue Rd., 8, Nanning, Guangxi, 530004, PR China
| | - Mohsin Ali
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Amjad Hussain
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Muhammad Hamzah Saleem
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yasser Nehela
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL, 33850, USA; Department of Agricultural Botany, Faculty of Agriculture, Tanta University, Tanta, Egypt
| | - Muhammad Aamir Sohail
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Agha Mushtaque Ahmed
- Department of Entomology, Faculty of Crop Protection, Sindh Agriculture University Tando Jam, Sindh, Pakistan
| | - Kashif Ali Kubar
- Faculty of Agriculture, Lasbela University of Agriculture, Water and Marine Sciences, Uthal, 90150, Balochistan, Pakistan
| | - Shafaqat Ali
- Department of Environmental Sciences and Engineering, Government College University Allama Iqbal Road, 38000, Faisalabad, Pakistan
| | - Kamal Usman
- Agricultural Research Station, Office of VP for Research & Graduate Studies, Qatar University, 2713, Doha, Qatar
| | - Hakim Manghwar
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang, Jiangxi, 332900, China.
| | - Lei Zhou
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
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Pandey SS, Hendrich C, Andrade MO, Wang N. Candidatus Liberibacter: From Movement, Host Responses, to Symptom Development of Citrus Huanglongbing. PHYTOPATHOLOGY 2022; 112:55-68. [PMID: 34609203 DOI: 10.1094/phyto-08-21-0354-fi] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Candidatus Liberibacter spp. are fastidious α-proteobacteria that cause multiple diseases on plant hosts of economic importance, including the most devastating citrus disease: Huanglongbing (HLB). HLB was reported in Asia a century ago but has since spread worldwide. Understanding the pathogenesis of Candidatus Liberibacter spp. remains challenging as they are yet to be cultured in artificial media and infect the phloem, a sophisticated environment that is difficult to manipulate. Despite those challenges, tremendous progress has been made on Ca. Liberibacter pathosystems. Here, we first reviewed recent studies on genetic information of flagellar and type IV pili biosynthesis, their expression profiles, and movement of Ca. Liberibacter spp. inside the plant and insect hosts. Next, we reviewed the transcriptomic, proteomic, and metabolomic studies of susceptible and tolerant plant genotypes to Ca. Liberibacter spp. infection and how Ca. Liberibacter spp. adapt in plants. Analyses of the interactions between plants and Ca. Liberibacter spp. imply the involvement of immune response in the Ca. Liberibacter pathosystems. Lastly, we reviewed how Ca. Liberibacter spp. movement inside and interactions with plants lead to symptom development.
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Affiliation(s)
- Sheo Shankar Pandey
- Citrus Research and Education Center, Department of Microbiology and Cell Sciences, University of Florida, Lake Alfred, FL 33850, U.S.A
| | - Connor Hendrich
- Citrus Research and Education Center, Department of Microbiology and Cell Sciences, University of Florida, Lake Alfred, FL 33850, U.S.A
| | - Maxuel O Andrade
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Centre for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Sciences, University of Florida, Lake Alfred, FL 33850, U.S.A
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da Cruz MA, Neves CSVJ, de Carvalho DU, Colombo RC, Bai J, Yada IFU, Leite Junior RP, Tazima ZH. Five Rootstocks for "Emperor" Mandarin Under Subtropical Climate in Southern Brazil. FRONTIERS IN PLANT SCIENCE 2021; 12:777871. [PMID: 34987531 PMCID: PMC8722343 DOI: 10.3389/fpls.2021.777871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
Rootstocks modulate several characteristics of citrus trees, including vegetative growth, fruit yield and quality, and resistance or tolerance to pests, diseases, soil drought, and salinity, among other factors. There is a shortage of scion and rootstock cultivars among the combinations planted in Brazil. "Ponkan" mandarin and "Murcott" tangor grafted on "Rangpur" lime comprise the majority of the commercial mandarin orchards in Brazil. This low genetic diversity of citrus orchards can favor pest and disease outbreaks. This study aimed to evaluate the agronomic performance, Huanglongbing (HLB) tolerance, and fruit quality of "Emperor" mandarin on five different rootstocks for nine cropping seasons under the subtropical soil-climate conditions of the North region of the state of Paraná, Brazil. The experimental design was a randomized block, with six replications, two trees per block, and five rootstocks, including "Rangpur" lime, "Cleopatra," and "Sunki" mandarins, "Swingle" citrumelo, and "Fepagro C-13" citrange. The evaluations included tree growth, yield performance, fruit quality, and HLB disease incidence. "Emperor" mandarin trees grafted on "Rangpur" lime and "Swingle" citrumelo had early fruiting and high yield efficiency. "Rangpur" lime also induced the lowest tree growth, but low fruit quality. Trees on "Swingle" citrumelo and "Fepagro C-13" citrange showed low scion and rootstock affinity and produced fruits with high total soluble solids (TSS), with a lower number of seeds for those from trees on "Fepagro C-13" citrange. "Cleopatra" and "Sunki" mandarins induced higher juice content, while fruits from trees on "Cleopatra" also had higher TSS/titratable acidity (TA) ratio. "Emperor" mandarin trees were susceptible to HLB regardless of the rootstocks. Overall, "Cleopatra" and "Sunki" mandarins, "Swingle" citrumelo, and "Fepagro C-13" are more suitable rootstocks for "Emperor" mandarin under Brazilian subtropical conditions than "Rangpur" lime.
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Affiliation(s)
- Maria Aparecida da Cruz
- Horticultural Research Laboratory, ARS, United States Department of Agriculture (USDA), Fort Pierce, FL, United States
- Centro de Ciências Agrárias, Universidade Estadual de Londrina, Londrina, Brazil
- Área de Fitotecnia, Instituto de Desenvolvimento Rural do Paraná, Londrina, Brazil
| | | | - Deived Uilian de Carvalho
- Centro de Ciências Agrárias, Universidade Estadual de Londrina, Londrina, Brazil
- Área de Fitotecnia, Instituto de Desenvolvimento Rural do Paraná, Londrina, Brazil
| | - Ronan Carlos Colombo
- Centro de Ciências Agrárias, Universidade Federal Tecnológica do Paraná, Francisco Beltrão, Brazil
| | - Jinhe Bai
- Horticultural Research Laboratory, ARS, United States Department of Agriculture (USDA), Fort Pierce, FL, United States
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10
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Hu B, Rao MJ, Deng X, Pandey SS, Hendrich C, Ding F, Wang N, Xu Q. Molecular signatures between citrus and Candidatus Liberibacter asiaticus. PLoS Pathog 2021; 17:e1010071. [PMID: 34882744 PMCID: PMC8659345 DOI: 10.1371/journal.ppat.1010071] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Citrus Huanglongbing (HLB), also known as citrus greening, is one of the most devastating citrus diseases worldwide. Candidatus Liberibacter asiaticus (CLas) is the most prevalent strain associated with HLB, which is yet to be cultured in vitro. None of the commercial citrus cultivars are resistant to HLB. The pathosystem of Ca. Liberibacter is complex and remains a mystery. In this review, we focus on the recent progress in genomic research on the pathogen, the interaction of host and CLas, and the influence of CLas infection on the transcripts, proteins, and metabolism of the host. We have also focused on the identification of candidate genes for CLas pathogenicity or the improvements of HLB tolerance in citrus. In the end, we propose potentially promising areas for mechanistic studies of CLas pathogenicity, defense regulators, and genetic improvement for HLB tolerance/resistance in the future.
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Affiliation(s)
- Bin Hu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Ministry of Agriculture), Huazhong Agricultural University, Wuhan, Hubei, China
| | - Muhammad Junaid Rao
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Ministry of Agriculture), Huazhong Agricultural University, Wuhan, Hubei, China
| | - Xiuxin Deng
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Ministry of Agriculture), Huazhong Agricultural University, Wuhan, Hubei, China
| | - Sheo Shankar Pandey
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida, United States of America
| | - Connor Hendrich
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida, United States of America
| | - Fang Ding
- Hubei Key Laboratory of Plant Pathology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida, United States of America
| | - Qiang Xu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Ministry of Agriculture), Huazhong Agricultural University, Wuhan, Hubei, China
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11
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Identification of citrus greening based on visual symptoms: A grower's diagnostic toolkit. Heliyon 2021; 7:e08387. [PMID: 34841106 PMCID: PMC8605348 DOI: 10.1016/j.heliyon.2021.e08387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/01/2021] [Accepted: 11/11/2021] [Indexed: 11/23/2022] Open
Abstract
Citrus greening is one of the world's most serious diseases of citrus that affects all cultivars and causes the systematic death of trees worldwide. The disease is caused mostly by the bacteria Candidatus Liberibacter species. The wind, rain, and touch of infected workers cannot transmit this infectious disease. The Asian Citrus Psyllid (ACP), a minuscule insect, is one of the main vectors that transmit the disease by feeding on citrus leaves. Citrus greening management is also quite expensive since no successful treatment for the cure has been found, except to remove all affected vegetables from healthy crops to eliminate the bacterial spread. Citrus greening is also the most challenging task, as signs of other citrus diseases and nutritional deficiencies are identical. The major signs of this disease are asymmetrical, blotchy mottling patterns on leaves. Here, several visible indications of citrus greening were addressed, which will enable farmers at the root level to detect and avoid this condition prior to its having a dramatic influence on citrus plantations. We also talked about the pen test method to determine symptoms as symmetrical or asymmetrical throughout the mid-vine, regardless of whether they are impacted by citrus greening or lack of nutrients.
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12
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Deng H, Zhang Y, Reuss L, Suh JH, Yu Q, Liang G, Wang Y, Gmitter FG. Comparative Leaf Volatile Profiles of Two Contrasting Mandarin Cultivars against Candidatus Liberibacter asiaticus Infection Illustrate Huanglongbing Tolerance Mechanisms. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:10869-10884. [PMID: 34499509 DOI: 10.1021/acs.jafc.1c02875] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Huanglongbing (HLB), presumably caused by Candidatus Liberibacter asiaticus (CaLas), is a devastating citrus disease worldwide. While all citrus are affected by HLB, some cultivars display greater tolerance; however, the underlying mechanisms are not fully understood. Here, volatile changes in HLB-tolerant LB8-9 Sugar Belle (SB) and HLB-sensitive Murcott mandarins after CaLas infection were comprehensively compared to determine if specific volatiles are associated with HLB responses and to discern the underlying tolerance mechanisms. These cultivars emitted qualitatively and quantitatively different volatiles in response to HLB induced by artificial graft or natural psyllid inoculation. Increasing amounts of total volatiles and de novo-synthesized new volatiles were two key responses to HLB of both cultivars. Markers potentially associated with HLB and host susceptibility were identified. Terpenoid biosynthetic pathway, green leaf volatile, and thymol metabolic pathways responsive to CaLas infection were dramatically altered. SB mandarin allows simultaneous defense and growth, contributing to its greater HLB tolerance.
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Affiliation(s)
- Honghong Deng
- College of Horticulture, Institute of Pomology and Olericulture, Sichuan Agricultural University, Chengdu 611130, China
- Citrus Research and Education Center, Horticultural Science, University of Florida, Lake Alfred, Florida 33850, United States
- College of Horticulture and Landscape Architecture, Horticultural Science, Southwest University, Chongqing 400715, China
| | - Yi Zhang
- Citrus Research and Education Center, Horticultural Science, University of Florida, Lake Alfred, Florida 33850, United States
| | - Laura Reuss
- Citrus Research and Education Center, Food Science and Human Nutrition, University of Florida, Lake Alfred, Florida 33850, United States
| | - Joon Hyuk Suh
- Citrus Research and Education Center, Food Science and Human Nutrition, University of Florida, Lake Alfred, Florida 33850, United States
| | - Qibin Yu
- Citrus Research and Education Center, Horticultural Science, University of Florida, Lake Alfred, Florida 33850, United States
| | - Guolu Liang
- College of Horticulture and Landscape Architecture, Horticultural Science, Southwest University, Chongqing 400715, China
| | - Yu Wang
- Citrus Research and Education Center, Food Science and Human Nutrition, University of Florida, Lake Alfred, Florida 33850, United States
| | - Fred G Gmitter
- Citrus Research and Education Center, Horticultural Science, University of Florida, Lake Alfred, Florida 33850, United States
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13
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Suh JH, Tang X, Zhang Y, Gmitter FG, Wang Y. Metabolomic Analysis Provides New Insight Into Tolerance of Huanglongbing in Citrus. FRONTIERS IN PLANT SCIENCE 2021; 12:710598. [PMID: 34421957 PMCID: PMC8371912 DOI: 10.3389/fpls.2021.710598] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 06/30/2021] [Indexed: 05/17/2023]
Abstract
There have been efforts to develop citrus cultivars that are tolerant of Huanglongbing (HLB), a catastrophic phloem-limited disease. Previous studies demonstrated that continuous plant growth with phloem regeneration is one of the major characteristics of HLB tolerance. In this study, the metabolic mechanisms of HLB tolerance in citrus were elucidated using a multiple pathway-targeted metabolomic approach. Comparative analysis of healthy and infected HLB-tolerant and HLB-sensitive mandarin cultivars (Citrus reticulata) revealed differentially expressed metabolic responses among different groups. Pathway enrichment analysis indicated aspartate and glutamate metabolism, purine metabolism, and biosynthesis of plant hormones were upregulated in the tolerant group, except salicylic acid signaling. Catabolic pathways linked to energy-yielding metabolism were also upregulated in the tolerant group. These metabolisms and pathways were interconnected with each other, unveiling a pivotal metabolic network associated with HLB tolerance. In the network, auxins and cytokinins, the plant hormones responsible for plant growth and phloem regeneration, were accumulated. In addition, purine metabolites serving as energy carriers and nitrogen sources of plants were increased. Only salicylic acid-related metabolites for plant defense responses were decreased in the tolerant group. Our findings may evidence the strategy of HLB-tolerant cultivars that sustain plant growth and phloem formation rather than displaying direct plant defense to overcome the disease.
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Affiliation(s)
| | | | | | | | - Yu Wang
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
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14
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Mahmoud LM, Huyck PJ, Vincent CI, Gmitter FG, Grosser JW, Dutt M. Physiological Responses and Gene Expression Patterns in Open-Pollinated Seedlings of a Pummelo-Mandarin Hybrid Rootstock Exposed to Salt Stress and Huanglongbing. PLANTS 2021; 10:plants10071439. [PMID: 34371641 PMCID: PMC8309399 DOI: 10.3390/plants10071439] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 07/08/2021] [Accepted: 07/09/2021] [Indexed: 02/04/2023]
Abstract
Huanglongbing (HLB), caused by the phloem-limited bacterium Candidatus Liberibacter asiaticus (CaLas), is the primary biotic stress causing significant economic damage to the global citrus industry. Among the abiotic stresses, salinity affects citrus production worldwide, especially in arid and coastal regions. In this study, we evaluated open-pollinated seedlings of the S10 (a diploid rootstock produced from a cross between two siblings of the Hirado Buntan Pink pummelo (Citrus maxima (Burm.) Merr.) with the Shekwasha mandarin (Citrus reticulata Blanco)) for their ability to tolerate HLB and salinity stresses. In a greenhouse study, ‘Valencia’ sweet orange (either HLB-positive or negative) was grafted onto six clonally propagated lines generated from the screened seedlings in the greenhouse and the trees were irrigated with 150 mM NaCl after eight months of successful grafting and detection of CaLas in the leaf petioles. Cleopatra mandarin was used as a salt-tolerant and HLB-sensitive rootstock control. CaLas infection was monitored using a quantitative polymerase chain reaction before and after NaCl treatments. Following three months of NaCl treatment, ‘Valencia’ leaves on the S10 rootstock seedlings recorded lower levels of chlorophyll content compared to Cleopatra under similar conditions. Malondialdehyde content was higher in HLB-infected ‘Valencia’ grafted onto Cleopatra than in the S10 lines. Several plant defense-related genes were significantly upregulated in the S10 lines. Antioxidant and Na+ co-transporter genes were differentially regulated in these lines. Based on our results, selected S10 lines have potential as salt-tolerant rootstocks of ‘Valencia’ sweet orange under endemic HLB conditions. However, it is necessary to propagate selected lines through tissue culture or cuttings because of the high percentage of zygotic seedlings derived from S10.
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Affiliation(s)
- Lamiaa M. Mahmoud
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
- Pomology Department, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt
| | - Patrick J. Huyck
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
| | - Christopher I. Vincent
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
| | - Frederick G. Gmitter
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
| | - Jude W. Grosser
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
| | - Manjul Dutt
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850, USA; (L.M.M.); (P.J.H.); (C.I.V.); (F.G.G.J.); (J.W.G.)
- Correspondence:
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15
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Huang CY, Niu D, Kund G, Jones M, Albrecht U, Nguyen L, Bui C, Ramadugu C, Bowman KD, Trumble J, Jin H. Identification of citrus immune regulators involved in defence against Huanglongbing using a new functional screening system. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:757-766. [PMID: 33108698 PMCID: PMC8051609 DOI: 10.1111/pbi.13502] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 09/27/2020] [Accepted: 10/18/2020] [Indexed: 05/24/2023]
Abstract
Huanglongbing (HLB) is the most devastating citrus disease in the world. Almost all commercial citrus varieties are susceptible to the causal bacterium, Candidatus Liberibacter asiaticus (CLas), which is transmitted by the Asian citrus psyllid (ACP). Currently, there are no effective management strategies to control HLB. HLB-tolerant traits have been reported in some citrus relatives and citrus hybrids, which offer a direct pathway for discovering natural defence regulators to combat HLB. Through comparative analysis of small RNA profiles and target gene expression between an HLB-tolerant citrus hybrid (Poncirus trifoliata × Citrus reticulata) and a susceptible citrus variety, we identified a panel of candidate defence regulators for HLB-tolerance. These regulators display similar expression patterns in another HLB-tolerant citrus relative, with a distinct genetic and geographic background, the Sydney hybrid (Microcitrus virgata). Because the functional validation of candidate regulators in tree crops is always challenging, we developed a novel rapid functional screening method, using a C. Liberibacter solanacearum (CLso)/potato psyllid/Nicotiana benthamiana interaction system to mimic the natural transmission and infection circuit of the HLB complex. When combined with efficient virus-induced gene silencing in N. benthamiana, this innovative and cost-effective screening method allows for rapid identification and functional characterization of regulators involved in plant immune responses against HLB, such as the positive regulator BRCA1-Associated Protein, and the negative regulator Vascular Associated Death Protein.
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Affiliation(s)
- Chien Yu Huang
- Department of Microbiology and Plant PathologyCenter for Plant Cell BiologyUniversity of CaliforniaRiversideCAUSA
| | - DongDong Niu
- Department of Microbiology and Plant PathologyCenter for Plant Cell BiologyUniversity of CaliforniaRiversideCAUSA
- Department of Plant ProtectionNanjing Agriculture UniversityNanjingChina
| | | | | | - Ute Albrecht
- Horticultural Sciences DepartmentSouthwest Florida Research and Education CenterUniversity of Florida/IFASImmokaleeFLUSA
| | - Lincoln Nguyen
- Department of Microbiology and Plant PathologyCenter for Plant Cell BiologyUniversity of CaliforniaRiversideCAUSA
| | - Christine Bui
- Department of Microbiology and Plant PathologyCenter for Plant Cell BiologyUniversity of CaliforniaRiversideCAUSA
| | | | - Kim D. Bowman
- US Horticultural Research LaboratoryAgricultural Research ServiceUSDAFort PierceFLUSA
| | | | - Hailing Jin
- Department of Microbiology and Plant PathologyCenter for Plant Cell BiologyUniversity of CaliforniaRiversideCAUSA
- Institute for Integrative Genome BiologyUCRCAUSA
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16
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Munir S, Li Y, He P, He P, He P, Cui W, Wu Y, Li X, Li Q, Zhang S, Xiong Y, Lu Z, Wang W, Zong K, Yang Y, Yang S, Mu C, Wen H, Wang Y, Guo J, Karunarathna SC, He Y. Defeating Huanglongbing Pathogen Candidatus Liberibacter asiaticus With Indigenous Citrus Endophyte Bacillus subtilis L1-21. FRONTIERS IN PLANT SCIENCE 2021; 12:789065. [PMID: 35126416 PMCID: PMC8813962 DOI: 10.3389/fpls.2021.789065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/26/2021] [Indexed: 05/11/2023]
Abstract
Huanglongbing (HLB) has turned into a devastating botanical pandemic of citrus crops, caused by Candidatus Liberibacter asiaticus (CLas). However, until now the disease has remained incurable with very limited control strategies available. Restoration of the affected microbiomes in the diseased host through the introduction of an indigenous endophyte Bacillus subtilis L1-21 isolated from healthy citrus may provide an innovative approach for disease management. A novel half-leaf method was developed in vitro to test the efficacy of the endophyte L1-21 against CLas. Application of B. subtilis L1-21 at 104 colony forming unit (cfu ml-1) resulted in a 1,000-fold reduction in the CLas copies per gram of leaf midrib (107 to 104) in 4 days. In HLB-affected citrus orchards over a period of 2 years, the CLas incidence was reduced to < 3%, and CLas copies declined from 109 to 104 g-1 of diseased leaf midribs in the endophyte L1-21 treated trees. Reduction in disease incidence may corroborate a direct or an indirect biocontrol effect of the endophytes as red fluorescent protein-labeled B. subtilis L1-21 colonized and shared niche (phloem) with CLas. This is the first large-scale study for establishing a sustainable HLB control strategy through citrus endophytic microbiome restructuring using an indigenous endophyte.
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Affiliation(s)
- Shahzad Munir
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Yongmei Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Pengbo He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Pengfei He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Pengjie He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Wenyan Cui
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Yixin Wu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Xingyu Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Qi Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
| | - Sixiang Zhang
- Binchuan Institute for Food and Medicine Inspection and Testing, Binchuan, China
| | - Yangsu Xiong
- Binchuan Institute for Food and Medicine Inspection and Testing, Binchuan, China
| | - Zhanjun Lu
- College of Life Sciences, Gannan Normal University, Ganzhou, China
| | - Wenbiao Wang
- Binchuan Institute for Food and Medicine Inspection and Testing, Binchuan, China
| | - Kexian Zong
- Binchuan Institute for Food and Medicine Inspection and Testing, Binchuan, China
| | - Yongchao Yang
- Institute of Upland Crops, Wenshan Academy of Agricultural Sciences, Wenshan, China
| | - Shaocong Yang
- Institute of Crop Fertilization, Yuxi Academy of Agricultural Sciences, Yuxi, China
| | - Chan Mu
- Institute of Crop Fertilization, Yuxi Academy of Agricultural Sciences, Yuxi, China
| | - Heming Wen
- Institute of Upland Crops, Wenshan Academy of Agricultural Sciences, Wenshan, China
| | - Yuehu Wang
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
| | - Jun Guo
- Institute of Tropical and Subtropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan, China
| | - Samantha C. Karunarathna
- Center for Mountain Futures (CMF), Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
| | - Yueqiu He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
- *Correspondence: Yueqiu He
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17
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Nehela Y, Killiny N. Revisiting the Complex Pathosystem of Huanglongbing: Deciphering the Role of Citrus Metabolites in Symptom Development. Metabolites 2020; 10:E409. [PMID: 33066072 PMCID: PMC7600524 DOI: 10.3390/metabo10100409] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/02/2020] [Accepted: 10/06/2020] [Indexed: 12/20/2022] Open
Abstract
Huanglongbing (HLB), formerly known as citrus greening disease, is one of the most devastating bacterial diseases in citrus worldwide. HLB is caused by 'Candidatus Liberibacter asiaticus' bacterium and transmitted by Diaphorina citri. Both 'Ca. L. asiaticus' and its vector manipulate the host metabolism to fulfill their nutritional needs and/or to neutralize the host defense responses. Herein, we discuss the history of HLB and the complexity of its pathosystem as well as the geographical distribution of its pathogens and vectors. Recently, our recognition of physiological events associated with 'Ca. L. asiaticus' infection and/or D. citri-infestation has greatly improved. However, the roles of citrus metabolites in the development of HLB symptoms are still unclear. We believe that symptom development of HLB disease is a complicated process and relies on a multilayered metabolic network which is mainly regulated by phytohormones. Citrus metabolites play vital roles in the development of HLB symptoms through the modulation of carbohydrate metabolism, phytohormone homeostasis, antioxidant pathways, or via the interaction with other metabolic pathways, particularly involving amino acids, leaf pigments, and polyamines. Understanding how 'Ca. L. asiaticus' and its vector, D. citri, affect the metabolic pathways of their host is critical for developing novel, sustainable strategies for HLB management.
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Affiliation(s)
- Yasser Nehela
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd., Lake Alfred, FL 33850, USA;
- Department of Agricultural Botany, Faculty of Agriculture, Tanta University, Tanta 31511, Egypt
| | - Nabil Killiny
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd., Lake Alfred, FL 33850, USA;
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18
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Belabess Z, Sagouti T, Rhallabi N, Tahiri A, Massart S, Tahzima R, Lahlali R, Jijakli MH. Citrus Psorosis Virus: Current Insights on a Still Poorly Understood Ophiovirus. Microorganisms 2020; 8:microorganisms8081197. [PMID: 32781662 PMCID: PMC7465697 DOI: 10.3390/microorganisms8081197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/27/2020] [Accepted: 08/03/2020] [Indexed: 01/11/2023] Open
Abstract
Citrus psorosis was reported for the first time in Florida in 1896 and was confirmed as a graft-transmissible disease in 1934. Citrus psorosis virus (CPsV) is the presumed causal agent of this disease. It is considered as a type species of the genus Ophiovirus, within the family Aspiviridae. CPsV genome is a negative single-stranded RNA (-ssRNA) with three segments. It has a coat protein (CP) of 48 kDa and its particles are non-enveloped with naked filamentous nucleocapsids existing as either circular open structures or collapsed pseudo-linear forms. Numerous rapid and sensitive immuno-enzymatic and molecular-based detection methods specific to CPsV are available. CPsV occurrence in key citrus growing regions across the world has been spurred the establishment of the earliest eradication and virus-free budwood programs. Despite these efforts, CPsV remains a common and serious challenge in several countries and causes a range of symptoms depending on the isolate, the cultivar, and the environment. CPsV can be transmitted mechanically to some herbaceous hosts and back to citrus. Although CPsV was confirmed to be seedborne, the seed transmission is not efficient. CPsV natural spread has been increasing based on both CPsV surveys detection and specific CPsV symptoms monitoring. However, trials to ensure its transmission by a soil-inhabiting fungus and one aphid species have been unsuccessful. Psorosis disease control is achieved using CPsV-free buds for new plantations, launching budwood certification and indexing programs, and establishing a quarantine system for the introduction of new varieties. The use of natural resistance to control CPsV is very challenging. Transgenic resistance to at least some CPsV isolates is now possible in at least some sweet orange varieties and constitutes a promising biotechnological alternative to control CPsV. This paper provides an overview of the most remarkable achievements in CPsV research that could improve the understanding of the disease and lead the development of better control strategies.
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Affiliation(s)
- Zineb Belabess
- Plant Protection Laboratory. INRA, Centre Régional de la Recherche Agronomique (CRRA), Oujda 60000, Qualipole de Berkane, 63300 Berkane, Morocco;
| | - Tourya Sagouti
- Faculté des Sciences et Techniques de Mohammedia, Laboratoire de Virologie, Microbiologie et Qualité/Ecotoxicologie et Biodiversité, 20650 Mohammedia, Morocco; (T.S.); (N.R.)
| | - Naima Rhallabi
- Faculté des Sciences et Techniques de Mohammedia, Laboratoire de Virologie, Microbiologie et Qualité/Ecotoxicologie et Biodiversité, 20650 Mohammedia, Morocco; (T.S.); (N.R.)
| | - Abdessalem Tahiri
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, 50001 Meknes, Morocco;
| | - Sébastien Massart
- Integrated and Urban Plant Pathology Laboratory, Gembloux Agro BioTech, University of Liege, 25030 Gembloux, Belgium; (S.M.); (R.T.); (M.H.J.)
| | - Rachid Tahzima
- Integrated and Urban Plant Pathology Laboratory, Gembloux Agro BioTech, University of Liege, 25030 Gembloux, Belgium; (S.M.); (R.T.); (M.H.J.)
| | - Rachid Lahlali
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, 50001 Meknes, Morocco;
- Correspondence: ; Tel.: +212-55-30-02-39
| | - M. Haissam Jijakli
- Integrated and Urban Plant Pathology Laboratory, Gembloux Agro BioTech, University of Liege, 25030 Gembloux, Belgium; (S.M.); (R.T.); (M.H.J.)
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20
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Song F, Bai F, Wang J, Wu L, Jiang Y, Pan Z. Influence of Citrus Scion/Rootstock Genotypes on Arbuscular Mycorrhizal Community Composition under Controlled Environment Condition. PLANTS 2020; 9:plants9070901. [PMID: 32708770 PMCID: PMC7412222 DOI: 10.3390/plants9070901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 01/01/2023]
Abstract
Citrus is vegetatively propagated by grafting for commercial production, and most rootstock cultivars of citrus have scarce root hairs, thus heavily relying on mutualistic symbiosis with arbuscular mycorrhizal fungi (AMF) for mineral nutrient uptake. However, the AMF community composition, and its differences under different citrus scion/rootstock genotypes, were largely unknown. In this study, we investigated the citrus root-associated AMF diversity and richness, and assessed the influence of citrus scion/rootstock genotypes on the AMF community composition in a controlled condition, in order to exclude interferences from environmental factors and agricultural practices. As a result, a total of 613,408 Glomeromycota tags were detected in the citrus roots, and 46 AMF species were annotated against the MAARJAM database. Of these, 39 species belonged to Glomus, indicating a dominant role of the Glomus AMF in the symbiosis with citrus. PCoA analysis indicated that the AMF community’s composition was significantly impacted by both citrus scion and rootstock genotypes, but total samples were clustered according to rootstock genotype rather than scion genotype. In addition, AMF α diversity was significantly affected merely by rootstock genotype. Thus, rootstock genotype might exert a greater impact on the AMF community than scion genotype. Taken together, this study provides a comprehensive insight into the AMF community in juvenile citrus plants, and reveals the important effects of citrus genotype on AMF community composition.
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Affiliation(s)
- Fang Song
- Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Fuxi Bai
- Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Juanjuan Wang
- Institute National Agro-Technical Extension and Service Center (NATESC), Ministry of Agriculture, Beijing 100000, China
| | - Liming Wu
- Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Yingchun Jiang
- Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430064, China
| | - Zhiyong Pan
- College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
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Nehela Y, Killiny N. The unknown soldier in citrus plants: polyamines-based defensive mechanisms against biotic and abiotic stresses and their relationship with other stress-associated metabolites. PLANT SIGNALING & BEHAVIOR 2020; 15:1761080. [PMID: 32408848 PMCID: PMC8570725 DOI: 10.1080/15592324.2020.1761080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 05/07/2023]
Abstract
Citrus plants are challenged by a broad diversity of abiotic and biotic stresses, which definitely alter their growth, development, and productivity. In order to survive the various stressful conditions, citrus plants relay on multi-layered adaptive strategies, among which is the accumulation of stress-associated metabolites that play vital and complex roles in citrus defensive responses. These metabolites included amino acids, organic acids, fatty acids, phytohormones, polyamines (PAs), and other secondary metabolites. However, the contribution of PAs pathways in citrus defense responses is poorly understood. In this review article, we will discuss the recent metabolic, genetic, and molecular evidence illustrating the potential roles of PAs in citrus defensive responses against biotic and abiotic stressors. We believe that PAs-based defensive role, against biotic and abiotic stress in citrus, is involving the interaction with other stress-associated metabolites, particularly phytohormones. The knowledge gained so far about PAs-based defensive responses in citrus underpins our need for further genetic manipulation of PAs biosynthetic genes to produce transgenic citrus plants with modulated PAs content that may enhance the tolerance of citrus plants against stressful conditions. In addition, it provides valuable information for the potential use of PAs or their synthetic analogs and their emergence as a promising approach to practical applications in citriculture to enhance stress tolerance in citrus plants.
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Affiliation(s)
- Yasser Nehela
- Citrus Research and Education Center and Department of Plant Pathology, IFAS, University of Florida, Lake Alfred, FL, USA
| | - Nabil Killiny
- Citrus Research and Education Center and Department of Plant Pathology, IFAS, University of Florida, Lake Alfred, FL, USA
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22
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Attaran E, Berim A, Killiny N, Beyenal H, Gang DR, Omsland A. Controlled replication of 'Candidatus Liberibacter asiaticus' DNA in citrus leaf discs. Microb Biotechnol 2020; 13:747-759. [PMID: 31958876 PMCID: PMC7111093 DOI: 10.1111/1751-7915.13531] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/10/2019] [Accepted: 12/14/2019] [Indexed: 12/13/2022] Open
Abstract
'Candidatus Liberibacter asiaticus' is a fastidious bacterium and a putative agent of citrus greening disease (a.k.a., huanglongbing, HLB), a significant agricultural disease that affects citrus fruit quality and tree health. In citrus, 'Ca. L. asiaticus' is phloem limited. Lack of culture tools to study 'Ca. L. asiaticus' complicates analysis of this important organism. To improve understanding of 'Ca. L. asiaticus'-host interactions including parameters that affect 'Ca. L. asiaticus' replication, methods suitable for screening pathogen responses to physicochemical and nutritional variables are needed. We describe a leaf disc-based culture assay that allows highly selective measurement of changes in 'Ca. L. asiaticus' DNA within plant tissue incubated under specific physicochemical and nutritional conditions. qPCR analysis targeting the hypothetical gene CD16-00155 (strain A4) allowed selective quantification of 'Ca. L. asiaticus' DNA content within infected tissue. 'Ca. L. asiaticus' DNA replication was observed in response to glucose exclusively under microaerobic conditions, and the antibiotic amikacin further enhanced 'Ca. L. asiaticus' DNA replication. Metabolite profiling revealed a moderate impact of 'Ca. L. asiaticus' on the ability of leaf tissue to metabolize and respond to glucose.
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Affiliation(s)
- Elham Attaran
- Paul G. Allen School for Global Animal HealthWashington State UniversityPullmanWAUSA
| | - Anna Berim
- Institute of Biological ChemistryWashington State UniversityPullmanWAUSA
| | - Nabil Killiny
- Plant Pathology DepartmentCitrus Research and Education CenterUniversity of FloridaLake AlfredFLUSA
| | - Haluk Beyenal
- Gene and Linda Voiland School of Chemical Engineering and BioengineeringWashington State UniversityPullmanWAUSA
| | - David R. Gang
- Institute of Biological ChemistryWashington State UniversityPullmanWAUSA
| | - Anders Omsland
- Paul G. Allen School for Global Animal HealthWashington State UniversityPullmanWAUSA
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23
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Huang L, Grosser J, Gmitter FG, Sims CA, Wang Y. Effects of Scion/Rootstock Combination on Flavor Quality of Orange Juice from Huanglongbing (HLB)-Affected Trees: A Two-Year Study of the Targeted Metabolomics. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:3286-3296. [PMID: 32052973 DOI: 10.1021/acs.jafc.9b07934] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The bacterial disease Huanglongbing (HLB) has been causing large economic losses in the citrus industry worldwide. Aimed at unraveling the mechanisms of scion/rootstock combination on improving HLB-affected orange juice quality, a specific scion/rootstock combination field trial was designed using three sibling rootstocks and two late-maturing sweet orange scion cultivars. Scion/rootstock combination significantly improved the overall consumer liking of orange juice from the HLB-affected trees. Rootstocks showed significant effects on the consumer liking and overall flavor, while scions had significant effects on the freshness and overall orange flavor intensity of the juice. A PLS-DA model combined with KEGG pathway enrichment analysis and some biomarker metabolites further indicated that scions mainly affected metabolism of alanine, aspartate, and glutamate in orange fruits. Meanwhile, rootstocks had an impact on the biosynthetic pathways of secondary metabolites. Sugars and organic acids were not closely correlated with the overall liking and sensory perception of orange juice. Rather, flavonoids, terpenoids, and volatile aromas played important roles in improving consumer overall liking. These results indicated that an optimum tolerant scion/rootstock combination can make a positive contribution toward improved fruit or juice quality from HLB-affected citrus trees.
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Affiliation(s)
- Linhua Huang
- Citrus Research Institute, Southwest University, Xiema, Beibei, Chongqing 400712, China
- Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850, United States
| | - Jude Grosser
- Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850, United States
| | - Frederick G Gmitter
- Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850, United States
| | - Charles A Sims
- Food Science and Human Nutrition, University of Florida, 572 Newell Drive, Gainesville, Florida 32611, United States
| | - Yu Wang
- Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850, United States
- Food Science and Human Nutrition, University of Florida, 572 Newell Drive, Gainesville, Florida 32611, United States
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24
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Pitino M, Sturgeon K, Dorado C, Cano LM, Manthey JA, Shatters RG, Rossi L. Quercus leaf extracts display curative effects against Candidatus Liberibacter asiaticus that restore leaf physiological parameters in HLB-affected citrus trees. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 148:70-79. [PMID: 31945669 DOI: 10.1016/j.plaphy.2020.01.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/09/2020] [Accepted: 01/09/2020] [Indexed: 05/04/2023]
Abstract
Citrus greening, also called Huanglongbing (HLB), is one of the most destructive citrus diseases worldwide. It is caused by the fastidious gram-negative α-proteobacteria bacterium Candidatus Liberibacter asiaticus (CLas) and vectored by the Asian citrus psyllid (ACP), Diaphorina citri. Currently, there is no cure for HLB, no compounds have been successful in controlling HLB, and no sustainable management practices have been established for the disease. Thus, searching for alternative citrus greening disease mitigation strategies is considered an urgent priority for a sustainable citrus industry. The aim of this study was to use compounds extracted from oak, Quercus hemisphaerica, and to assess the antibacterial effects of these against CLas-infected citrus plants. The application of aqueous oak leaf extracts showed substantial inhibitory effects against CLas in citrus plants and the activity of genes related to starch. Significant differences were also observed in plant phenotypic and physiological traits after treatments. Citrus plants treated with oak extracts displayed an increase in stomatal conductance, chlorophyll content and nutrient uptake concurrently with a reduction of CLas titer, when compared to citrus plants treated with just water. The information provided from this study suggests a new management treatment program to effectively deal with the HLB disease.
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Affiliation(s)
- Marco Pitino
- Department of Plant Pathology, University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Ft. Pierce, FL, 34945, USA
| | - Kasie Sturgeon
- Department of Plant Pathology, University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Ft. Pierce, FL, 34945, USA
| | - Christina Dorado
- Horticultural Research Laboratory, U.S. Department of Agriculture, Agricultural Research Services, Ft. Pierce, FL, 34945, USA
| | - Liliana M Cano
- Department of Plant Pathology, University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Ft. Pierce, FL, 34945, USA
| | - John A Manthey
- Horticultural Research Laboratory, U.S. Department of Agriculture, Agricultural Research Services, Ft. Pierce, FL, 34945, USA
| | - Robert G Shatters
- Horticultural Research Laboratory, U.S. Department of Agriculture, Agricultural Research Services, Ft. Pierce, FL, 34945, USA
| | - Lorenzo Rossi
- Department of Horticultural Sciences, University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Ft. Pierce, FL, 34945, USA.
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25
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Yao L, Yu Q, Huang M, Song Z, Grosser J, Chen S, Wang Y, Gmitter FG. Comparative iTRAQ proteomic profiling of sweet orange fruit on sensitive and tolerant rootstocks infected by 'Candidatus Liberibacter asiaticus'. PLoS One 2020; 15:e0228876. [PMID: 32059041 PMCID: PMC7021301 DOI: 10.1371/journal.pone.0228876] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/23/2020] [Indexed: 01/12/2023] Open
Abstract
Citrus Huanglongbing (HLB), which is also known as citrus greening, is a destructive disease continuing to devastate citrus production worldwide. Although all citrus varieties can be infected with 'Candidatus Liberibacter asiaticus' (CaLas), a certain level of HLB tolerance of scion varieties can be conferred by some rootstocks. To understand the effects of rootstock varieties on orange fruit under CaLas stress, comparative iTRAQ proteomic profilings were conducted, using fruit from 'Valencia' sweet orange grafted on the sensitive ('Swingle') and tolerant rootstocks (a new selection called '46x20-04-48') infected by CaLas as experimental groups, and the same plant materials without CaLas infection as controls. The symptomatic fruit on 'Swingle' had 573 differentially-expressed (DE) proteins in comparison with their healthy fruit on the same rootstock, whereas the symptomatic fruit on '46x20-04-48' had 263 DE proteins. Many defense-associated proteins were down-regulated in the symptomatic fruit on 'Swingle' rootstock that were seldom detected in the symptomatic fruit on the '46x20-04-48' rootstock, especially the proteins involved in the jasmonate biosynthesis (AOC4), jasmonate signaling (ASK2, RUB1, SKP1, HSP70T-2, and HSP90.1), protein hydrolysis (RPN8A and RPT2a), and vesicle trafficking (SNAREs and Clathrin) pathways. Therefore, we predict that the down-regulated proteins involved in the jasmonate signaling pathway and vesicle trafficking are likely to be related to citrus sensitivity to the CaLas pathogen.
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Affiliation(s)
- Lixiao Yao
- Citrus Research Institute, Southwest University, Chongqing, China
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Qibin Yu
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Ming Huang
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Zhen Song
- Citrus Research Institute, Southwest University, Chongqing, China
| | - Jude Grosser
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Shanchun Chen
- Citrus Research Institute, Southwest University, Chongqing, China
| | - Yu Wang
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Frederick G. Gmitter
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
- * E-mail:
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26
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Munir S, Li Y, He P, He P, Ahmed A, Wu Y, He Y. Unraveling the metabolite signature of citrus showing defense response towards Candidatus Liberibacter asiaticus after application of endophyte Bacillus subtilis L1-21. Microbiol Res 2020; 234:126425. [PMID: 32035248 DOI: 10.1016/j.micres.2020.126425] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/17/2020] [Accepted: 01/30/2020] [Indexed: 10/25/2022]
Abstract
Huanglongbing (HLB) is one of the most serious citrus diseases, caused by phloem limited endophytic bacteria Candidatus Liberibacter asiaticus (Clas), affecting worldwide citrus production. Metabolomics approaches were employed to gain insight into mechanisms involved in defense against Clas in endophyte Bacillus subtilis L1-21 treated diseased and healthy citrus plants. Using LC-ESI-MS/MS, we compared the metabolic profile of citrus plants before and after treatment with endophyte L1-21. Our analysis indicated large differences in citrus metabolites after endophyte L1-21 application. In total, seven hundred and fourty two metabolites were detected with highest percentage recorded for organic acids, flavone, amino acid derivatives, flavone C-glycosides, nucleotide derivatives, and flavonol. Interestingly, differentially expressed metabolites (DEMs) analysis revealed the amino acids, such as lysine and tyrosine which are involved in plant defense agianst pathogen attack were regulated in diseased citrus plants after endophyte application (padj<0.05). In addition, other important metabolites up-regulated were xanthine, leucic acid, and α-Linolenic acid implicated in different plant defense pathways against Clas. Furhter, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed important pathways related to purine metabolism, biotin metabolism, and betalain biosynthesis, terpenoid-quinone biosynthesis, phenylalanine, tyrosine and lysine biosynthesis, isoflavonoid biosynthesis (padj<0.05). Taken together, this is the first study using native endophytes in diseased and healthy state of citrus which has proven to be useful in disease management by strengthening the defense of citrus to Clas pathogen.
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Affiliation(s)
- Shahzad Munir
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Yongmei Li
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Pengfei He
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Pengbo He
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Ayesha Ahmed
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Yixin Wu
- National and Local Joint Engineering Research Center for Screening and Application of Microbial Strains, Kunming 650217, Yunnan, China; College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Yueqiu He
- State Key Laboratory for Conservation and Utilization of Bio-resources in Yunnan, Yunnan Agricultural University, Kunming 650201, Yunnan, China; National and Local Joint Engineering Research Center for Screening and Application of Microbial Strains, Kunming 650217, Yunnan, China; College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, Yunnan, China.
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The Power of Electropenetrography in Enhancing Our Understanding of Host Plant-Vector Interactions. INSECTS 2019; 10:insects10110407. [PMID: 31731698 PMCID: PMC6920982 DOI: 10.3390/insects10110407] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 11/13/2019] [Accepted: 11/13/2019] [Indexed: 12/31/2022]
Abstract
The invasive Asian citrus psyllid, Diaphorina citri (Hemiptera: Liviidae), is the primary vector of the phloem-infecting bacterium, Candidatus Liberibacter asiaticus. Candidatus L. asiaticus is the putative causal agent of Huanglongbing (HLB) disease, a destructive disease of Citrus. While many Citrus species are susceptible to D. citri probing and HLB disease, there are marked behavioral differences in D. citri probing responses and Ca. Liberibacter asiaticus infection severity among Citrus species. Using four mandarin hybrid selections and pummelo plants variably resistant to D. citri probing, oviposition, and survival, we explored probing differences using electropenetrography (EPG), conducted an oviposition and survival study, and determined host plant metabolites using gas-chromatography mass-spectroscopy (GC-MS). We found thirty-seven D. citri probing variables to be significantly different among tested mandarin selections and pummelo, in addition to differential oviposition and survivorship abilities on tested plants. We found sixty-three leaf metabolites with eight being significantly different among tested mandarin selections and pummelo. Detailed analysis of probing behavior, oviposition, survivorship, and host plant metabolite concentrations reveals the complex, layered resistance mechanisms utilized by resistant Citrus against D. citri probing. EPG is a powerful technology for screening Asian citrus psyllid resistant Citrus to elucidate host plant-vector interactions, with an aim to minimize vector probing and eliminate the spread of the bacterial pathogen, Ca. L. asiaticus.
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Gas Biosensor Arrays Based on Single-Stranded DNA-Functionalized Single-Walled Carbon Nanotubes for the Detection of Volatile Organic Compound Biomarkers Released by Huanglongbing Disease-Infected Citrus Trees. SENSORS 2019; 19:s19214795. [PMID: 31689974 PMCID: PMC6865013 DOI: 10.3390/s19214795] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 10/31/2019] [Accepted: 11/01/2019] [Indexed: 02/02/2023]
Abstract
Volatile organic compounds (VOCs) released by plants are closely associated with plant metabolism and can serve as biomarkers for disease diagnosis. Huanglongbing (HLB), also known as citrus greening or yellow shoot disease, is a lethal threat to the multi-billion-dollar citrus industry. Early detection of HLB is vital for removal of susceptible citrus trees and containment of the disease. Gas sensors are applied to monitor the air quality or toxic gases owing to their low-cost fabrication, smooth operation, and possible miniaturization. Here, we report on the development, characterization, and application of electrical biosensor arrays based on single-walled carbon nanotubes (SWNTs) decorated with single-stranded DNA (ssDNA) for the detection of four VOCs-ethylhexanol, linalool, tetradecene, and phenylacetaldehyde-that serve as secondary biomarkers for detection of infected citrus trees during the asymptomatic stage. SWNTs were noncovalently functionalized with ssDNA using π-π interaction between the nucleotide and sidewall of SWNTs. The resulting ssDNA-SWNT hybrid structure and device properties were investigated using Raman spectroscopy, ultraviolet (UV) spectroscopy, and electrical measurements. To monitor changes in the four VOCs, gas biosensor arrays consisting of bare SWNTs before and after being decorated with different ssDNA were employed to determine the different concentrations of the four VOCs. The data was processed using principal component analysis (PCA) and neural net fitting (NNF).
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UAV-Based High Throughput Phenotyping in Citrus Utilizing Multispectral Imaging and Artificial Intelligence. REMOTE SENSING 2019. [DOI: 10.3390/rs11040410] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Traditional plant breeding evaluation methods are time-consuming, labor-intensive, and costly. Accurate and rapid phenotypic trait data acquisition and analysis can improve genomic selection and accelerate cultivar development. In this work, a technique for data acquisition and image processing was developed utilizing small unmanned aerial vehicles (UAVs), multispectral imaging, and deep learning convolutional neural networks to evaluate phenotypic characteristics on citrus crops. This low-cost and automated high-throughput phenotyping technique utilizes artificial intelligence (AI) and machine learning (ML) to: (i) detect, count, and geolocate trees and tree gaps; (ii) categorize trees based on their canopy size; (iii) develop individual tree health indices; and (iv) evaluate citrus varieties and rootstocks. The proposed remote sensing technique was able to detect and count citrus trees in a grove of 4,931 trees, with precision and recall of 99.9% and 99.7%, respectively, estimate their canopy size with overall accuracy of 85.5%, and detect, count, and geolocate tree gaps with a precision and recall of 100% and 94.6%, respectively. This UAV-based technique provides a consistent, more direct, cost-effective, and rapid method to evaluate phenotypic characteristics of citrus varieties and rootstocks.
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30
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Dala-Paula BM, Plotto A, Bai J, Manthey JA, Baldwin EA, Ferrarezi RS, Gloria MBA. Effect of Huanglongbing or Greening Disease on Orange Juice Quality, a Review. FRONTIERS IN PLANT SCIENCE 2019; 9:1976. [PMID: 30723488 PMCID: PMC6350258 DOI: 10.3389/fpls.2018.01976] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 12/19/2018] [Indexed: 05/15/2023]
Abstract
Huanglongbing (HLB) or citrus greening is the most severe citrus disease, currently devastating the citrus industry worldwide. The presumed causal bacterial agent Candidatus Liberibacter spp. affects tree health as well as fruit development, ripening and quality of citrus fruits and juice. Fruit from infected orange trees can be either symptomatic or asymptomatic. Symptomatic oranges are small, asymmetrical and greener than healthy fruit. Furthermore, symptomatic oranges show higher titratable acidity and lower soluble solids, solids/acids ratio, total sugars, and malic acid levels. Among flavor volatiles, ethyl butanoate, valencene, decanal and other ethyl esters are lower, but many monoterpenes are higher in symptomatic fruit compared to healthy and asymptomatic fruit. The disease also causes an increase in secondary metabolites in the orange peel and pulp, including hydroxycinnamic acids, limonin, nomilin, narirutin, and hesperidin. Resulting from these chemical changes, juice made from symptomatic fruit is described as distinctly bitter, sour, salty/umami, metallic, musty, and lacking in sweetness and fruity/orange flavor. Those effects are reported in both Valencia and Hamlin oranges, two cultivars that are commercially processed for juice in Florida. The changes in the juice are reflective of a decrease in quality of the fresh fruit, although not all fresh fruit varieties have been tested. Earlier research showed that HLB-induced off-flavor was not detectable in juice made with up to 25% symptomatic fruit in healthy juice, by chemical or sensory analysis. However, a blend with a higher proportion of symptomatic juice would present a detectable and recognizable off flavor. In some production regions, such as Florida in the United States, it is increasingly difficult to find fruit not showing HLB symptoms. This review analyzes and discusses the effects of HLB on orange juice quality in order to help the citrus industry manage the quality of orange juice, and guide future research needs.
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Affiliation(s)
- Bruno M. Dala-Paula
- Food Biochemistry Laboratory, Department of Food, College of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Anne Plotto
- United States Department of Agriculture, Agricultural Research Service, Horticultural Laboratory, Fort Pierce, FL, United States
| | - Jinhe Bai
- United States Department of Agriculture, Agricultural Research Service, Horticultural Laboratory, Fort Pierce, FL, United States
| | - John A. Manthey
- United States Department of Agriculture, Agricultural Research Service, Horticultural Laboratory, Fort Pierce, FL, United States
| | - Elizabeth A. Baldwin
- United States Department of Agriculture, Agricultural Research Service, Horticultural Laboratory, Fort Pierce, FL, United States
| | - Rhuanito S. Ferrarezi
- Indian River Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Fort Pierce, FL, United States
| | - Maria Beatriz A. Gloria
- Food Biochemistry Laboratory, Department of Food, College of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, Brazil
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Yao L, Yu Q, Huang M, Hung W, Grosser J, Chen S, Wang Y, Gmitter FG. Proteomic and metabolomic analyses provide insight into the off-flavour of fruits from citrus trees infected with ' Candidatus Liberibacter asiaticus'. HORTICULTURE RESEARCH 2019; 6:31. [PMID: 30792870 PMCID: PMC6375920 DOI: 10.1038/s41438-018-0109-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/11/2018] [Accepted: 11/15/2018] [Indexed: 05/18/2023]
Abstract
Orange fruit from trees infected by 'Candidatus Liberibacter asiaticus' (CaLas) often do not look fully mature and exhibit off-flavours described as bitter, harsh, and metallic rather than juicy and fruity. Although previous studies have been carried out to understand the effect of CaLas on the flavour of orange juice using metabolomic methods, the mechanisms leading to the off-flavour that occurs in Huanglongbing (HLB)-symptomatic fruit are not well understood. In this study, fruits were collected from symptomatic and healthy Valencia sweet orange (Citrus sinensis) trees grafted on Swingle (C. paradisi X Poncirus trifoliata) rootstock. Isobaric tags for relative and absolute quantification (iTRAQ) and gas chromatography-mass spectrometry (GC-MS) were used to measure the proteins, sugars, organic acids, amino acids, and volatile terpenoids. The results showed that most of the differentially expressed proteins involved in glycolysis, the tricarboxylic acid (TCA) cycle and amino-acid biosynthesis were degraded, and terpenoid metabolism was significantly downregulated in the symptomatic fruit. Valencene, limonene, 3-carene, linalool, myrcene, and α-terpineol levels were significantly lower in fruit from CaLas-infected trees than from healthy trees. Similar phenomena were observed for sucrose and glucose. Our study indicated that off-flavour of symptomatic fruit was associated with a reduction in the levels of terpenoid products and the downregulation of proteins in glycolysis, the TCA cycle, and the terpenoid biosynthesis pathway.
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Affiliation(s)
- Lixiao Yao
- Citrus Research Institute, Southwest University, Chongqing, China
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Qibin Yu
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Ming Huang
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Weilun Hung
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Jude Grosser
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Shanchun Chen
- Citrus Research Institute, Southwest University, Chongqing, China
| | - Yu Wang
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
| | - Frederick G. Gmitter
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL 33850 USA
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32
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Alseekh S, Bermudez L, de Haro LA, Fernie AR, Carrari F. Crop metabolomics: from diagnostics to assisted breeding. Metabolomics 2018; 14:148. [PMID: 30830402 DOI: 10.1007/s11306-018-1446-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/26/2018] [Indexed: 01/02/2023]
Abstract
BACKGROUND Until recently, plant metabolomics have provided a deep understanding on the metabolic regulation in individual plants as experimental units. The application of these techniques to agricultural systems subjected to more complex interactions is a step towards the implementation of translational metabolomics in crop breeding. AIM OF REVIEW We present here a review paper discussing advances in the knowledge reached in the last years derived from the application of metabolomic techniques that evolved from biomarker discovery to improve crop yield and quality. KEY SCIENTIFIC CONCEPTS OF REVIEW Translational metabolomics applied to crop breeding programs.
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Affiliation(s)
- Saleh Alseekh
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
- Center of Plant System Biology and Biotechnology, 4000, Plovdiv, Bulgaria
| | - Luisa Bermudez
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (IB-INTA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), PO Box 25, B1686WAA, Castelar, Argentina
- Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Luis Alejandro de Haro
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (IB-INTA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), PO Box 25, B1686WAA, Castelar, Argentina
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Ciudad Universitaria, C1428EHA, Buenos Aires, Argentina
| | - Alisdair R Fernie
- Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
- Center of Plant System Biology and Biotechnology, 4000, Plovdiv, Bulgaria
| | - Fernando Carrari
- Instituto de Biotecnología, Instituto Nacional de Tecnología Agropecuaria (IB-INTA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), PO Box 25, B1686WAA, Castelar, Argentina.
- Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina.
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, São Paulo, 05508-090, Brazil.
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-UBA-CONICET), Ciudad Universitaria, C1428EHA, Buenos Aires, Argentina.
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Tang J, Ding Y, Nan J, Yang X, Sun L, Zhao X, Jiang L. Transcriptome sequencing and ITRAQ reveal the detoxification mechanism of Bacillus GJ1, a potential biocontrol agent for Huanglongbing. PLoS One 2018; 13:e0200427. [PMID: 30091977 PMCID: PMC6084860 DOI: 10.1371/journal.pone.0200427] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 06/26/2018] [Indexed: 11/18/2022] Open
Abstract
Huanglongbing (HLB) is the most serious disease affecting citrus production worldwide. No HLB-resistant citrus varieties exist. The HLB pathogen Candidatus Liberibacter asiaticus is nonculturable, increasing the difficulty of preventing and curing the disease. We successfully screened the biocontrol agent Bacillus GJ1 for the control of HLB in nursery-grown citrus plants. RNA sequencing (RNA-seq) of the transcriptome and isobaric tags for relative and absolute quantification of the proteome revealed differences in the detoxification responses of Bacillus GJ1-treated and -untreated Ca. L. asiaticus-infected citrus. Phylogenetic tree alignment showed that GJ1 was classified as B. amyloliquefaciens. The effect of eliminating the HLB pathogen was measured using real-time quantitative polymerase chain reaction (qPCR) and PCR. The results indicate that the rate of detoxification reached 50% after seven irrigations, of plants with an OD600nm≈1 Bacillus GJ1 suspension. Most importantly, photosynthesis-antenna proteins, photosynthesis, plant-pathogen interactions, and protein processing in the endoplasmic reticulum were significantly upregulated (padj < 0.05), as shown by the KEGG enrichment analysis of the transcriptomes; nine of the upregulated genes were validated by qPCR. Transcription factor analysis of the transcriptomes was performed, and 10 TFs were validated by qPCR. Cyanoamino acid metabolism, regulation of autophagy, isoflavonoid biosynthesis, starch and sucrose metabolism, protein export, porphyrin and chlorophyll metabolism, and carotenoid biosynthesis were investigated by KEGG enrichment analysis of the proteome, and significant differences were found in the expression of the genes involved in those pathways. Correlation analysis of the proteome and transcriptome showed common entries for the significantly different expression of proteins and the significantly different expression of genes in the GO and KEGG pathways, respectively. The above results reveal important information about the detoxification pathways.
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Affiliation(s)
- Jizhou Tang
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Yuanxi Ding
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jing Nan
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Xiangyu Yang
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Liang Sun
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Xiuyun Zhao
- College of life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Ling Jiang
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China.,National Indoor Conservation Center of Virus-free Germplasm of Fruit Crops, Huazhong Agricultural University, Wuhan, Hubei, China
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Killiny N, Hijaz F, Nehela Y, Hajeri S, Gowda S. Effects of δ-aminolevulinic acid dehydratase silencing on the primary and secondary metabolisms of citrus. PLANT DIRECT 2018; 2:e00072. [PMID: 31245736 PMCID: PMC6508816 DOI: 10.1002/pld3.72] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/18/2018] [Accepted: 06/26/2018] [Indexed: 05/07/2023]
Abstract
δ-aminolevulinic acid dehydratase (ALAD) is an important enzyme in tetrapyrrole synthesis. ALAD combines two δ-aminolevulinic acid (δ-ALA) molecules to form the pyrrole molecule, porphobilinogen, an important precursor for plant pigments involved in photosynthesis, respiration, and nutrient uptake. In this study, we investigated the effects of silencing of ALAD gene on citrus leaf pigments and metabolites. The ALAD enzyme was inhibited using virus-induced gene silencing (VIGS) technology using citrus tristeza virus (CTV). δ-ALA accumulated in citrus plants inoculated with the recombinant virus (CTV-tALAD) to silence ALAD and resulted in discrete yellow spots (yellow islands) and necrosis in leaves and stems. The levels of chlorophylls, starch, sucrose, trans- and cis-violaxanthin, and α- and β-cryptoxanthin were reduced in CTV-tALAD plants, whereas zeaxanthin was increased. The increase in zeaxanthin and the decrease in its precursors indicated that the reduction in chlorophylls resulted in light damage. Salicylic acid and jasmonic acid levels, as well as emission of (E)-α-bergamotene and (E)-β-farnesene, increased in CTV-tALAD plants indicating these plants were under stress. Our results showed that silencing of ALAD induces stress in plants and that VIGS using mild CTV strains is a promising technique to study biological function of citrus genes.
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Affiliation(s)
- Nabil Killiny
- Department of Plant PathologyCitrus Research and Education CenterIFASUniversity of FloridaLake AlfredFlorida
| | - Faraj Hijaz
- Department of Plant PathologyCitrus Research and Education CenterIFASUniversity of FloridaLake AlfredFlorida
| | - Yasser Nehela
- Department of Plant PathologyCitrus Research and Education CenterIFASUniversity of FloridaLake AlfredFlorida
| | - Subhas Hajeri
- Department of Plant PathologyCitrus Research and Education CenterIFASUniversity of FloridaLake AlfredFlorida
- Present address:
Citrus Pest Detection ProgramCentral California Tristeza Eradication AgencyTulareCalifornia
| | - Siddarame Gowda
- Department of Plant PathologyCitrus Research and Education CenterIFASUniversity of FloridaLake AlfredFlorida
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Kiefl J, Kohlenberg B, Hartmann A, Obst K, Paetz S, Krammer G, Trautzsch S. Investigation on Key Molecules of Huanglongbing (HLB)-Induced Orange Juice Off-flavor. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:2370-2377. [PMID: 28285516 DOI: 10.1021/acs.jafc.7b00892] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Orange fruits from huanglongbing (HLB)-infected trees do not fully mature and show a severe off-flavor described as bitter-harsh, metallic, and less juicy and fruity. The investigation of juice from HLB-infected (HLBOJ) and healthy control oranges (COJ) by gas chromatography-mass spectrometry showed higher concentrations of fruity esters, such as ethyl butyrate and ethyl 2-methylbutyrate, and soapy-waxy alkanals, such as octanal and decanal, in the COJ, whereas the HLBOJ showed higher concentrations of green aldehydes such as hexanal and degradation compounds of limonene and linalool such as α-terpineol. Application of aroma extract dilution analysis on terpeneless peel oil led to the identification of long-chained aldehydes such as ( E, E)-2,4-decadienal, ( Z)-8-tetradecenal, trans-4,5-epoxy-( E)-2-decenal, ( Z)-4-decenal, and octanal with the highest flavor dilution factors among 25 odor-active volatiles in the peel oil of healthy oranges. Taste-guided fractionation and identification of the HLBOJ secondary metabolites followed by sensory validation revealed that flavanoids such as hesperidin may modulate the flavor to evoke the unacceptable harsh/metallic taste impression. Quantitation of the bitter components showed good correlation between the limonoid and flavanoid concentrations with the off-flavor and quality of the oranges obtained throughout the season.
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Affiliation(s)
- Johannes Kiefl
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Birgit Kohlenberg
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Anja Hartmann
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Katja Obst
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Susanne Paetz
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Gerhard Krammer
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
| | - Stephan Trautzsch
- Symrise AG , Flavors Division Research & Technology , P.O. Box 1253, D-37601 Holzminden , Germany
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36
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Suh JH, Niu YS, Wang Z, Gmitter FG, Wang Y. Metabolic Analysis Reveals Altered Long-Chain Fatty Acid Metabolism in the Host by Huanglongbing Disease. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1296-1304. [PMID: 29328677 DOI: 10.1021/acs.jafc.7b05273] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Candidatus Liberibacter asiaticus (CLas) is the presumed causal agent of Huanglongbing, one of the most destructive diseases in citrus. However, the lipid metabolism component of host response to this pathogen has not been investigated well. Here, metabolic profiling of a variety of long-chain fatty acids and their oxidation products was first performed to elucidate altered host metabolic responses of disease. Fatty acid signals were found to decrease obviously in response to disease regardless of cultivar. Several lipid oxidation products strongly correlated with those fatty acids were also consistently reduced in the diseased group. Using a series of statistical methods and metabolic pathway mapping, we found significant markers contributing to the pathological symptoms and identified their internal relationships and metabolic network. Our findings suggest that the infection of CLas may cause the altered metabolism of long-chain fatty acids, possibly leading to manipulation of the host's defense derived from fatty acids.
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Affiliation(s)
| | - Yue S Niu
- Department of Mathematics, University of Arizona , 617 North Santa Rita Avenue, Tucson, Arizona 85721, United States
| | - Zhibin Wang
- Department of Citrus Breeding, The Citrus Research Institute, Southwest University , 2# Tiansheng Rd, Beibei, Chongqing 400715, China
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37
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Sétamou M, Alabi OJ, Simpson CR, Jifon JL. Contrasting amino acid profiles among permissive and non-permissive hosts of Candidatus Liberibacter asiaticus, putative causal agent of Huanglongbing. PLoS One 2017; 12:e0187921. [PMID: 29236706 PMCID: PMC5728503 DOI: 10.1371/journal.pone.0187921] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/27/2017] [Indexed: 12/13/2022] Open
Abstract
Huanglongbing is a devastating disease of citrus. In this study, a comprehensive profile of phloem sap amino acids (AA) in four permissive host plants of Candidatus Liberibacter asiaticus (CLas) and three non-permissive Rutaceae plants was conducted to gain a better understanding of host factors that may promote or suppress the bacterium. The AA profiles of Diaphorina citri nymphs and adults were similarly analyzed. A total of 38 unique AAs were detected in phloem sap of the various plants and D. citri samples, with phloem sap of young shoots containing more AAs and at higher concentrations than their mature counterparts. All AAs detected in phloem sap of non-permissive plants were also present in CLas -permissive hosts plus additional AAs in the latter class of plants. However, the relative composition of 18 commonly shared AAs varied between CLas -permissive hosts and non-permissive plants. Multivariate analysis with a partial least square discriminant methodology revealed a total of 12 AAs as major factors affecting CLas host status, of which seven were positively related to CLas tolerance/resistance and five positively associated with CLas susceptibility. Most of the AAs positively associated with CLas susceptibility were predominantly of the glutamate family, notably stressed-induced AAs such as arginine, GABA and proline. In contrast, AAs positively correlated with CLas tolerance/resistance were mainly of the serine family. Further analysis revealed that whereas the relative proportions of AAs positively associated with CLas susceptibility did not vary with host developmental stages, those associated with CLas tolerance/resistance increased with flush shoot maturity. Significantly, the proline-to-glycine ratio was determined to be an important discriminating factor for CLas permissivity with higher values characteristic of CLas -permissive hosts. This ratio could be exploited as a biomarker in HLB-resistance breeding programs.
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Affiliation(s)
- Mamoudou Sétamou
- Texas A&M University-Kingsville Citrus Center, Weslaco, United States of America
| | - Olufemi J. Alabi
- Department of Plant Pathology & Microbiology, Texas A&M AgriLife Research and Extension Center, Weslaco, TX, United States of America
| | - Catherine R. Simpson
- Texas A&M University-Kingsville Citrus Center, Weslaco, United States of America
| | - John L. Jifon
- Department of Horticultural Sciences, Texas A&M AgriLife Research and Extension Center, Weslaco, TX, United States of America
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Rawat N, Kumar B, Albrecht U, Du D, Huang M, Yu Q, Zhang Y, Duan YP, Bowman KD, Gmitter FG, Deng Z. Genome resequencing and transcriptome profiling reveal structural diversity and expression patterns of constitutive disease resistance genes in Huanglongbing-tolerant Poncirus trifoliata and its hybrids. HORTICULTURE RESEARCH 2017; 4:17064. [PMID: 29152310 PMCID: PMC5686287 DOI: 10.1038/hortres.2017.64] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/07/2017] [Accepted: 10/10/2017] [Indexed: 05/22/2023]
Abstract
Huanglongbing (HLB) is the most destructive bacterial disease of citrus worldwide. While most citrus varieties are susceptible to HLB, Poncirus trifoliata, a close relative of Citrus, and some of its hybrids with Citrus are tolerant to HLB. No specific HLB tolerance genes have been identified in P. trifoliata but recent studies have shown that constitutive disease resistance (CDR) genes were expressed at much higher levels in HLB-tolerant Poncirus hybrids and the expression of CDR genes was modulated by Candidatus Liberibacter asiaticus (CLas), the pathogen of HLB. The current study was undertaken to mine and characterize the CDR gene family in Citrus and Poncirus and to understand its association with HLB tolerance in Poncirus. We identified 17 CDR genes in two citrus genomes, deduced their structures, and investigated their phylogenetic relationships. We revealed that the expansion of the CDR family in Citrus seems to be due to segmental and tandem duplication events. Through genome resequencing and transcriptome sequencing, we identified eight CDR genes in the Poncirus genome (PtCDR1-PtCDR8). The number of SNPs was the highest in PtCDR2 and the lowest in PtCDR7. Most of the deletion and insertion events were observed in the UTR regions of Citrus and Poncirus CDR genes. PtCDR2 and PtCDR8 were in abundance in the leaf transcriptomes of two HLB-tolerant Poncirus genotypes and were also upregulated in HLB-tolerant, Poncirus hybrids as revealed by real-time PCR analysis. These two CDR genes seem to be good candidate genes for future studies of their role in citrus-CLas interactions.
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Affiliation(s)
- Nidhi Rawat
- University of Florida, IFAS, Gulf Coast Research and Education Center, Wimauma, FL, USA
| | - Brajendra Kumar
- Ocimum BioSolutions Ltd., Royal Demeure, Plot no. 12/2, Sector- 1, HUDA Techno Enclave, Madhapur, Hyderabad, India
| | - Ute Albrecht
- University of Florida, IFAS, Southwest Florida Research and Education Center, Immokalee, FL, USA
| | - Dongliang Du
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA
| | - Ming Huang
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA
| | - Qibin Yu
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA
| | - Yi Zhang
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA
| | - Yong-Ping Duan
- U.S. Horticultural Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Fort Pierce, FL, USA
| | - Kim D Bowman
- U.S. Horticultural Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Fort Pierce, FL, USA
| | - Fred G Gmitter
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA
| | - Zhanao Deng
- University of Florida, IFAS, Gulf Coast Research and Education Center, Wimauma, FL, USA
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Wang N, Pierson EA, Setubal JC, Xu J, Levy JG, Zhang Y, Li J, Rangel LT, Martins J. The Candidatus Liberibacter-Host Interface: Insights into Pathogenesis Mechanisms and Disease Control. ANNUAL REVIEW OF PHYTOPATHOLOGY 2017. [PMID: 28637377 DOI: 10.1146/annurev-phyto-080516-035513] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
"Candidatus Liberibacter" species are associated with economically devastating diseases of citrus, potato, and many other crops. The importance of these diseases as well as the proliferation of new diseases on a wider host range is likely to increase as the insects vectoring the "Ca. Liberibacter" species expand their territories worldwide. Here, we review the progress on understanding pathogenesis mechanisms of "Ca. Liberibacter" species and the control approaches for diseases they cause. We discuss the Liberibacter virulence traits, including secretion systems, putative effectors, and lipopolysaccharides (LPSs), as well as other important traits likely to contribute to disease development, e.g., flagella, prophages, and salicylic acid hydroxylase. The pathogenesis mechanisms of Liberibacters are discussed. Liberibacters secrete Sec-dependent effectors (SDEs) or other virulence factors into the phloem elements or companion cells to interfere with host targets (e.g., proteins or genes), which cause cell death, necrosis, or other phenotypes of phloem elements or companion cells, leading to localized cell responses and systemic malfunction of phloem. Receptors on the remaining organelles in the phloem, such as plastid, vacuole, mitochondrion, or endoplasmic reticulum, interact with secreted SDEs and/or other virulence factors secreted or located on the Liberibacter outer membrane to trigger cell responses. Some of the host genes or proteins targeted by SDEs or other virulence factors of Liberibacters serve as susceptibility genes that facilitate compatibility (e.g., promoting pathogen growth or suppressing immune responses) or disease development. In addition, Liberibacters trigger plant immunity response via pathogen-associated molecular patterns (PAMPs, such as lipopolysaccharides), which leads to premature cell death, callose deposition, or phloem protein accumulation, causing a localized response and/or systemic effect on phloem transportation. Physical presence of Liberibacters and their metabolic activities may disturb the function of phloem, via disrupting osmotic gradients, or the integrity of phloem conductivity. We also review disease management strategies, including promising new technologies. Citrus production in the presence of Huanglongbing is possible if the most promising management approaches are integrated. HLB management is discussed in the context of local, area-wide, and regional Huanglongbing/Asian Citrus Psyllid epidemiological zones. For zebra chip disease control, aggressive psyllid management enables potato production, although insecticide resistance is becoming an issue. Meanwhile, new technologies such as clustered regularly interspaced short palindromic repeat (CRISPR)-derived genome editing provide an unprecedented opportunity to provide long-term solutions.
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Affiliation(s)
- Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida 33850;
| | - Elizabeth A Pierson
- Department of Horticultural Sciences, Texas A&M University, College Station, Texas 77843
| | - João Carlos Setubal
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, 05508-000, Brazil
| | - Jin Xu
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida 33850;
| | - Julien G Levy
- Department of Horticultural Sciences, Texas A&M University, College Station, Texas 77843
| | - Yunzeng Zhang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida 33850;
| | - Jinyun Li
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, Florida 33850;
| | - Luiz Thiberio Rangel
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, 05508-000, Brazil
| | - Joaquim Martins
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, SP, 05508-000, Brazil
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40
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Killiny N, Valim MF, Jones SE, Omar AA, Hijaz F, Gmitter FG, Grosser JW. Metabolically speaking: Possible reasons behind the tolerance of 'Sugar Belle' mandarin hybrid to huanglongbing. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 116:36-47. [PMID: 28501026 DOI: 10.1016/j.plaphy.2017.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/12/2017] [Accepted: 05/02/2017] [Indexed: 05/03/2023]
Abstract
Huanglongbing (HLB) is currently considered the most destructive disease of citrus. Since its spread to the Americas, HLB has killed millions of trees and caused a sharp decline in production in many citrus growing regions. With the continuous spread of HLB disease in Florida and worldwide, there is an urgent need for the development of commercial citrus cultivars with a strong tolerance to HLB. Interestingly, field observations showed that some of the recently released mandarin hybrids such as 'Sugar Belle' were tolerant to HLB. In this study, we investigated the volatile and non-volatile metabolites of greenhouse-grown 'Sugar Belle' mandarin and four of its ancestors in order to understand why 'Sugar Belle' mandarin is relatively tolerant to HLB. Leaf volatiles were directly extracted with hexane and analyzed using gas chromatography-mass spectrometry (GC-MS). Leaf polar metabolites were extracted with a mixture of methanol:water (1:1, v/v), derivatized to their trimethylsilyl ethers, and analyzed using GC-MS. Forty-seven volatile compounds and forty-two polar metabolites were detected in 'Sugar Belle' mandarin leaves and its ancestors. 'Sugar Belle' was high in several volatiles such as α-thujene, para-cymene, γ-terpinene, thymol, β-elemene, and (E)-β-caryophyllene. Some of these volatiles, especially thymol, β-elemene, and (E)-β-caryophyllene are known for their anti-microbial activity. In addition, 'Sugar Belle' mandarin was the highest in synephrine, benzoic acid, ferulic acid, caffeic acid, chiro-inositol, fructose, glucose, threonic acid, saccharic acid, and galactaric acid, and the second in threonine, malic acid, and myo-inositol compared to the ancestors. Phenolic compounds such as benzoic, ferulic, and caffeic acids may act as antibacterial agents, whereas others like sugar alcohols may protect 'Sugar Belle' mandarin from stress during pathogen attack. The tolerance of 'Sugar Belle' and other newly released mandarin hybrids should be further evaluated using greenhouse controlled studies. If tolerance of these hybrids is confirmed, they could be used to replace the traditionally susceptible cultivars.
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Affiliation(s)
- Nabil Killiny
- Department of Plant Pathology, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA.
| | - Maria Filomena Valim
- Department of Plant Pathology, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA
| | - Shelley E Jones
- Department of Plant Pathology, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA
| | - Ahmad A Omar
- Horticultural Sciences Department, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA; Biochemistry Department, College of Agriculture, Zagazig University, Zagazig, 44511, Egypt
| | - Faraj Hijaz
- Department of Plant Pathology, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA
| | - Fred G Gmitter
- Horticultural Sciences Department, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA
| | - Jude W Grosser
- Horticultural Sciences Department, University of Florida, IFAS, CREC, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA
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Killiny N, Nehela Y, Hijaz F, Vincent CI. A plant pathogenic bacterium exploits the tricarboxylic acid cycle metabolic pathway of its insect vector. Virulence 2017; 9:99-109. [PMID: 28594267 PMCID: PMC5955482 DOI: 10.1080/21505594.2017.1339008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Huanglongbing in citrus is caused by a phloem-limited, uncultivable, gram-negative α-proteobacterium, Candidatus Liberibacter asiaticus (CLas). CLas is transmitted by the phloem-sucking insect, Diaphorina citri (Hemiptera: Liviidae), in a persistent, circulative, and propagative manner. In this study, we investigated the metabolomic and respiration rates changes in D. citri upon infection with CLas using gas chromatography-mass spectrometry (GC-MS) and gas exchange analysis. The level of glycine, L-serine, L-threonine, and gamma-amino butyric acid were higher in CLas-infected D. citri, while L-proline, L-aspartic acid, and L-pyroglutamic acid were lower in CLas-infected D. citri compared with the control. Citric acid was increased in CLas-infected D. citri, whereas malic and succinic acids were reduced. Interestingly, most of the reduced metabolites such as malate, succinate, aspartate, and L-proline are required for the growth of CLas. The increase in citric acid, serine, and glycine indicated that CLas induced glycolysis and the tricarboxylic acid cycle (TCA) in its vector. In agreement with the GC-MS results, the gene expression results also indicated that glycolysis and TCA were induced in CLas-infected D. citri and this was accompanied with an increases in respiration rate. Phosphoric acid and most of the sugar alcohols were higher in CLas-infected D. citri, indicating a response to the biotic stress or cell damage. Only slight increases in the levels of few sugars were observed in CLas-infected D. citri, which indicated that sugars are tightly regulated by D. citri. Our results indicated that CLas induces nutrient and energetic stress in its host insect. This study may provide some insights into the mechanism of colonization of CLas in its vector.
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Affiliation(s)
- Nabil Killiny
- a Citrus Research and Education Center, Department of Plant Pathology , IFAS, University of Florida , Lake Alfred , FL , USA
| | - Yasser Nehela
- a Citrus Research and Education Center, Department of Plant Pathology , IFAS, University of Florida , Lake Alfred , FL , USA
| | - Faraj Hijaz
- a Citrus Research and Education Center, Department of Plant Pathology , IFAS, University of Florida , Lake Alfred , FL , USA
| | - Christopher I Vincent
- b Citrus Research and Education Center, Department of Horticultural Science , IFAS, University of Florida , Lake Alfred , FL , USA
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Martinelli F, Dandekar AM. Genetic Mechanisms of the Devious Intruder Candidatus Liberibacter in Citrus. FRONTIERS IN PLANT SCIENCE 2017; 8:904. [PMID: 28620403 PMCID: PMC5449717 DOI: 10.3389/fpls.2017.00904] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 05/15/2017] [Indexed: 05/22/2023]
Affiliation(s)
- Federico Martinelli
- Dipartimento di Scienze Agrarie Alimentari e Forestali, Università degli Studi di PalermoPalermo, Italy
| | - Abhaya M. Dandekar
- Plant Sciences Department, University of California, DavisDavis, CA, United States
- *Correspondence: Abhaya M. Dandekar
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Martinelli F, Reagan RL, Dolan D, Fileccia V, Dandekar AM. Proteomic analysis highlights the role of detoxification pathways in increased tolerance to Huanglongbing disease. BMC PLANT BIOLOGY 2016; 16:167. [PMID: 27465111 PMCID: PMC4963945 DOI: 10.1186/s12870-016-0858-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 07/20/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Huanglongbing (HLB) disease is still the greatest threat to citriculture worldwide. Although there is not any resistance source in the Citrus germplasm, a certain level of moderated tolerance is present. A large-scale analysis of proteomic responses of Citrus may help: 1) clarifying physiological and molecular effects of disease progression, 2) validating previous data at transcriptomic level, and 3) identifying biomarkers for development of early diagnostics, short-term therapeutics and long-term genetic resistance. RESULTS In this work we have conducted a proteomic analysis of mature leaves of two Citrus genotypes with well-known differing tolerances to HLB: Navel orange (highly susceptible) and Volkameriana (moderately tolerant). Pathway enrichment analysis showed that amino acid degradation processes occurred to a larger degree in the Navel orange. No clear differences between the two genotypes were observed for primary metabolic pathways. The most important finding was that four glutathione-S-transferases were upregulated in Volkameriana and not in Navel orange. These proteins are involved in radical ion detoxification. CONCLUSIONS Upregulation of proteins involved in radical ion detoxification should be considered as an important mechanism of increased tolerance to HLB.
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Affiliation(s)
- Federico Martinelli
- Department of Agricultural and Forest Sciences, University of Palermo, viale delle scienze ed. 4, 90128 Palermo, Italy
| | - Russell L. Reagan
- Plant Sciences Department, University of California, One Shields Avenue, 95616 Davis, CA USA
| | - David Dolan
- Plant Sciences Department, University of California, One Shields Avenue, 95616 Davis, CA USA
| | - Veronica Fileccia
- Department of Agricultural and Forest Sciences, University of Palermo, viale delle scienze ed. 4, 90128 Palermo, Italy
| | - Abhaya M. Dandekar
- Plant Sciences Department, University of California, One Shields Avenue, 95616 Davis, CA USA
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