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Mohaimin AZ, Krishnamoorthy S, Shivanand P. A critical review on bioaerosols-dispersal of crop pathogenic microorganisms and their impact on crop yield. Braz J Microbiol 2024; 55:587-628. [PMID: 38001398 PMCID: PMC10920616 DOI: 10.1007/s42770-023-01179-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 11/07/2023] [Indexed: 11/26/2023] Open
Abstract
Bioaerosols are potential sources of pathogenic microorganisms that can cause devastating outbreaks of global crop diseases. Various microorganisms, insects and viroids are known to cause severe crop diseases impeding global agro-economy. Such losses threaten global food security, as it is estimated that almost 821 million people are underfed due to global crisis in food production. It is estimated that global population would reach 10 billion by 2050. Hence, it is imperative to substantially increase global food production to about 60% more than the existing levels. To meet the increasing demand, it is essential to control crop diseases and increase yield. Better understanding of the dispersive nature of bioaerosols, seasonal variations, regional diversity and load would enable in formulating improved strategies to control disease severity, onset and spread. Further, insights on regional and global bioaerosol composition and dissemination would help in predicting and preventing endemic and epidemic outbreaks of crop diseases. Advanced knowledge of the factors influencing disease onset and progress, mechanism of pathogen attachment and penetration, dispersal of pathogens, life cycle and the mode of infection, aid the development and implementation of species-specific and region-specific preventive strategies to control crop diseases. Intriguingly, development of R gene-mediated resistant varieties has shown promising results in controlling crop diseases. Forthcoming studies on the development of an appropriately stacked R gene with a wide range of resistance to crop diseases would enable proper management and yield. The article reviews various aspects of pathogenic bioaerosols, pathogen invasion and infestation, crop diseases and yield.
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Affiliation(s)
- Abdul Zul'Adly Mohaimin
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam
| | - Sarayu Krishnamoorthy
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam
| | - Pooja Shivanand
- Environmental and Life Sciences Programme, Faculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link, Bandar Seri Begawan, BE1410, Brunei Darussalam.
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2
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Wu QY, Ma R, Wang X, Ma YN, Wang ZS, Wei HL, Zhang XX. Effects of the invasion of Ralstonia solanacearum on soil microbial community structure in Wuhan, China. mSphere 2024; 9:e0066523. [PMID: 38231250 PMCID: PMC10900898 DOI: 10.1128/msphere.00665-23] [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: 10/31/2023] [Accepted: 12/13/2023] [Indexed: 01/18/2024] Open
Abstract
This study investigated the change in the microbiome of tomato rhizosphere soils after the invasion of Ralstonia solanacearum and analyzed the correlation between microbes and soil physicochemical properties. Diversity analyses of the bacteria in healthy and diseased rhizosphere soil samples (HRS and DRS) revealed that HRS had a higher species diversity and were compositionally different from DRS (P ≤ 0.05). Substantial differences in the relative abundance of Actinobacteria (37.52% vs 28.96%, P ≤ 0.05) and Proteobacteria (29.20% vs 35.59%, P ≤ 0.05) were identified in HRS and DRS, respectively. Taxonomic composition analysis showed ten differentially abundant genera, and seven of them (Gaiella, Roseisolibacter, Solirubrobacter, Kribbella, Acidibacter, Actinomarinicola, and Marmoricola) are more abundant in HRS. Soil pH and enzyme activities were negatively correlated with the abundance of R. solanacearum. The contents of total nitrogen (TN), total phosphorus (TP), total potassium (TK), alkaline nitrogen (alkaline N), available phosphorus (AP), available potassium (AK), NO3-N(NN), NH4+-N (AN), and organic matter (OM) were all significantly increased in DRS. The composition and richness of protozoa in the samples show significant differences. Cephalobus, Acrobeles, Heteromita, norank_Tylenchida, and Rotylenchulus were enriched in DRS. Microbial interaction networks revealed that the HRS networks were more complex than the DRS networks. Overall, the results of this study demonstrate that healthy soil has a more complex microbial community structure and higher enzyme activity, and the invasion of R. solanacearum damages the soil microbial system.IMPORTANCEHow does the invasion of Ralstonia solanacearum affect tomato rhizosphere bacteria and protozoa? Which microbial changes can affect the growth of R. solanacearum? To date, most research studies focus on bacteria, with little research on protozoa, and even less on the synergistic effects between protozoa and bacteria. Here, we analyzed the correlation between tomato rhizosphere bacterial and protozoan communities and soil physicochemical properties during the invasion of R. solanacearum. We found that the diversity and abundance of rhizosphere microorganisms in healthy rhizosphere soil samples (HRS) were significantly higher than those in diseased rhizosphere soil samples (DRS), and there were significant changes in soil pH and enzyme activity. Overall, in this study, the analysis of microbial changes during the invasion of R. solanacearum provides a theoretical basis for the prevention and control of bacterial wilt.
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Affiliation(s)
- Qian-Yu Wu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Rong Ma
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xing Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yi-Nan Ma
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhi-Shan Wang
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, China
| | - Hai-Lei Wei
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiao-Xia Zhang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
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Zhang W, Jiménez-Jiménez Á, Capellades M, Rencoret J, Kashyap A, Coll NS. Determination of De Novo Suberin-Lignin Ferulate Deposition in Xylem Tissue Upon Vascular Pathogen Attack. Methods Mol Biol 2024; 2722:117-127. [PMID: 37897604 DOI: 10.1007/978-1-0716-3477-6_9] [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] [Indexed: 10/30/2023]
Abstract
Plant vascular pathogens use different ways to reach the xylem vessels and cause devastating diseases in plants. Resistant and tolerant plants have evolved various defense mechanisms against vascular pathogens. Inducible physico-chemical structures, such as the formation of tyloses and wall reinforcements with phenolic polymers, are very effective barriers that confine the pathogen and prevent colonization. Here, we use a combination of classical histochemistry along with bright-field and fluorescence microscopy and two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy to visualize and characterize wall reinforcements containing phenolic wall polymers, namely, lignin, ferulates, and suberin, which occur in different xylem vasculature in response to pathogen attack.
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Affiliation(s)
- Weiqi Zhang
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Spain
| | - Álvaro Jiménez-Jiménez
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Spain
| | - Montserrat Capellades
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Spain
- Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Jorge Rencoret
- Institute of Natural Resources and Agrobiology of Seville (IRNAS), CSIC, Seville, Spain
| | - Anurag Kashyap
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Spain
- Department of Plant Pathology, Assam Agricultural University, Jorhat, Assam, India
| | - Núria S Coll
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Spain.
- Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain.
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Zhou L, Zhu T, Han S, Li S, Liu Y, Lin T, Qiao T. Changes in the Histology of Walnut ( Juglans regia L.) Infected with Phomopsis capsici and Transcriptome and Metabolome Analysis. Int J Mol Sci 2023; 24:ijms24054879. [PMID: 36902308 PMCID: PMC10003368 DOI: 10.3390/ijms24054879] [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: 01/15/2023] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023] Open
Abstract
Phomopsis capsici (P. capsici) causes branch blight of walnuts, which leads to significant economic loss. The molecular mechanism behind the response of walnuts remains unknown. Paraffin sectioning and transcriptome and metabolome analyses were performed to explore the changes in tissue structure, gene expression, and metabolic processes in walnut after infection with P. capsici. We found that P. capsici caused serious damage to xylem vessels during the infestation of walnut branches, destroying the structure and function of the vessels and creating obstacles to the transport of nutrients and water to the branches. The transcriptome results showed that differentially expressed genes (DEGs) were mainly annotated in carbon metabolism and ribosomes. Further metabolome analyses verified the specific induction of carbohydrate and amino acid biosynthesis by P. capsici. Finally, association analysis was performed for DEGs and differentially expressed metabolites (DEMs), which focused on the synthesis and metabolic pathways of amino acids, carbon metabolism, and secondary metabolites and cofactors. Three significant metabolites were identified: succinic semialdehyde acid, fumaric acid, and phosphoenolpyruvic acid. In conclusion, this study provides data reference on the pathogenesis of walnut branch blight and direction for breeding walnut to enhance its disease resistance.
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Shi H, Liu Y, Ding A, Wang W, Sun Y. Induced defense strategies of plants against Ralstonia solanacearum. Front Microbiol 2023; 14:1059799. [PMID: 36778883 PMCID: PMC9910360 DOI: 10.3389/fmicb.2023.1059799] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 01/05/2023] [Indexed: 01/27/2023] Open
Abstract
Plants respond to Ralstonia solanacearum infestation through two layers of immune system (PTI and ETI). This process involves the production of plant-induced resistance. Strategies for inducing resistance in plants include the formation of tyloses, gels, and callose and changes in the content of cell wall components such as cellulose, hemicellulose, pectin, lignin, and suberin in response to pathogen infestation. When R. solanacearum secrete cell wall degrading enzymes, plants also sense the status of cell wall fragments through the cell wall integrity (CWI) system, which activates deep-seated defense responses. In addition, plants also fight against R. solanacearum infestation by regulating the distribution of metabolic networks to increase the production of resistant metabolites and reduce the production of metabolites that are easily exploited by R. solanacearum. We review the strategies used by plants to induce resistance in response to R. solanacearum infestation. In particular, we highlight the importance of plant-induced physical and chemical defenses as well as cell wall defenses in the fight against R. solanacearum.
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Affiliation(s)
- Haoqi Shi
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, Shandong, China,The Graduate School, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yong Liu
- Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Sciences, Kunming, China,*Correspondence: Yong Liu, ; Anming Ding, ; Weifeng Wang,
| | - Anming Ding
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, Shandong, China,*Correspondence: Yong Liu, ; Anming Ding, ; Weifeng Wang,
| | - Weifeng Wang
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, Shandong, China,*Correspondence: Yong Liu, ; Anming Ding, ; Weifeng Wang,
| | - Yuhe Sun
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, Shandong, China
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6
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Metabolomic and transcriptomic analysis of roots of tobacco varieties resistant and susceptible to bacterial wilt. Genomics 2022; 114:110471. [DOI: 10.1016/j.ygeno.2022.110471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 08/10/2022] [Accepted: 08/27/2022] [Indexed: 12/21/2022]
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De La Fuente L, Merfa MV, Cobine PA, Coleman JJ. Pathogen Adaptation to the Xylem Environment. ANNUAL REVIEW OF PHYTOPATHOLOGY 2022; 60:163-186. [PMID: 35472277 DOI: 10.1146/annurev-phyto-021021-041716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A group of aggressive pathogens have evolved to colonize the plant xylem. In this vascular tissue, where water and nutrients are transported from the roots to the rest of the plant, pathogens must be able to thrive under acropetal xylem sap flow and scarcity of nutrients while having direct contact only with predominantly dead cells. Nevertheless, a few bacteria have adapted to exclusively live in the xylem, and various pathogens may colonize other plant niches without causing symptoms unless they reach the xylem. Once established, the pathogens modulate its physicochemical conditions to enhance their growth and virulence. Adaptation to the restrictive lifestyle of the xylem leads to genome reduction in xylem-restricted bacteria, as they have a higher proportion of pseudogenes in their genome. The basis of xylem adaptation is not completely understood; therefore, a need still exists for model systems to advance the knowledge on this topic.
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Affiliation(s)
- Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Jeffrey J Coleman
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
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Cornelis S, Hazak O. Understanding the root xylem plasticity for designing resilient crops. PLANT, CELL & ENVIRONMENT 2022; 45:664-676. [PMID: 34971462 PMCID: PMC9303747 DOI: 10.1111/pce.14245] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Xylem is the main route for transporting water, minerals and a myriad of signalling molecules within the plant. With its onset during early embryogenesis, the development of the xylem relies on hormone gradients, the activity of unique transcription factors, the distribution of mobile microRNAs, and receptor-ligand pathways. These regulatory mechanisms are often interconnected and together contribute to the plasticity of this water-conducting tissue. Environmental stresses, such as drought and salinity, have a great impact on xylem patterning. A better understanding of how the structural properties of the xylem are regulated in normal and stress conditions will be instrumental in developing crops of the future. In addition, vascular wilt pathogens that attack the xylem are becoming increasingly problematic. Further knowledge of xylem development in response to these pathogens will bring new solutions against these diseases. In this review, we summarize recent findings on the molecular mechanisms of xylem formation that largely come from Arabidopsis research with additional insights from tomato and monocot species. We emphasize the impact of abiotic factors and pathogens on xylem plasticity and the urgent need to uncover the underlying mechanisms. Finally, we discuss the multidisciplinary approach to model xylem capacities in crops.
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Affiliation(s)
- Salves Cornelis
- Department of BiologyUniversity of FribourgFribourgSwitzerland
| | - Ora Hazak
- Department of BiologyUniversity of FribourgFribourgSwitzerland
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Abebe AM, Oh CS, Kim HT, Choi G, Seo E, Yeam I, Lee JM. QTL-Seq Analysis for Identification of Resistance Loci to Bacterial Canker in Tomato. FRONTIERS IN PLANT SCIENCE 2022; 12:809959. [PMID: 35154207 PMCID: PMC8826648 DOI: 10.3389/fpls.2021.809959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
Bacterial canker caused by Clavibacter michiganensis (Cm) is one of the most economically important vascular diseases causing unilateral leaf wilting, stem canker, a bird's-eye lesion on fruit, and whole plant wilting in tomato. There is no commercially available cultivar with bacterial canker resistance, and genomics-assisted breeding can accelerate the development of cultivars with enhanced resistance. Solanum lycopersicum "Hawaii 7998" was found to show bacterial canker resistance. A Quantitative trait loci (QTL)-seq was performed to identify the resistance loci using 909 F2 individuals derived from a cross between S. lycopersicum "E6203" (susceptible) and "Hawaii 7998," and a genomic region (37.24-41.15 Mb) associated with bacterial canker resistance on chromosome 6 (Rcm6) was found. To dissect the Rcm6 region, 12 markers were developed and several markers were associated with the resistance phenotypes. Among the markers, the Rcm6-9 genotype completely matched with the phenotype in the 47 cultivars. To further validate the Rcm6 as a resistance locus and the Rcm6-9 efficiency, subsequent analysis using F2 and F3 progenies was conducted. The progeny individuals with homozygous resistance allele at the Rcm6-9 showed significantly lower disease severity than those possessing homozygous susceptibility alleles. Genomes of five susceptible and two resistant cultivars were analyzed and previously known R-genes were selected to find candidate genes for Rcm6. Nucleotide-binding leucine-rich repeat, receptor-like kinase, and receptor-like protein were identified to have putative functional mutations and show differential expression upon the Cm infection. The DNA markers and candidate genes will facilitate marker-assisted breeding and provide genetic insight of bacterial canker resistance in tomato.
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Affiliation(s)
- Alebel Mekuriaw Abebe
- Department of Horticultural Science, Kyungpook National University, Daegu, South Korea
| | - Chang-Sik Oh
- Department of Horticultural Biotechnology, College of Life Science, Kyung Hee University, Yongin, South Korea
| | - Hyoung Tae Kim
- Department of Horticultural Science, Kyungpook National University, Daegu, South Korea
| | - Giwon Choi
- Department of Horticultural Science, Kyungpook National University, Daegu, South Korea
| | - Eunyoung Seo
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Inhwa Yeam
- Department of Horticulture and Breeding, Andong National University, Andong, South Korea
| | - Je Min Lee
- Department of Horticultural Science, Kyungpook National University, Daegu, South Korea
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Shaw RK, Shen Y, Wang J, Sheng X, Zhao Z, Yu H, Gu H. Advances in Multi-Omics Approaches for Molecular Breeding of Black Rot Resistance in Brassica oleracea L. FRONTIERS IN PLANT SCIENCE 2021; 12:742553. [PMID: 34938304 PMCID: PMC8687090 DOI: 10.3389/fpls.2021.742553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/20/2021] [Indexed: 06/14/2023]
Abstract
Brassica oleracea is one of the most important species of the Brassicaceae family encompassing several economically important vegetables produced and consumed worldwide. But its sustainability is challenged by a range of pathogens, among which black rot, caused by Xanthomonas campestris pv. campestris (Xcc), is the most serious and destructive seed borne bacterial disease, causing huge yield losses. Host-plant resistance could act as the most effective and efficient solution to curb black rot disease for sustainable production of B. oleracea. Recently, 'omics' technologies have emerged as promising tools to understand the host-pathogen interactions, thereby gaining a deeper insight into the resistance mechanisms. In this review, we have summarized the recent achievements made in the emerging omics technologies to tackle the black rot challenge in B. oleracea. With an integrated approach of the omics technologies such as genomics, proteomics, transcriptomics, and metabolomics, it would allow better understanding of the complex molecular mechanisms underlying black rot resistance. Due to the availability of sequencing data, genomics and transcriptomics have progressed as expected for black rot resistance, however, other omics approaches like proteomics and metabolomics are lagging behind, necessitating a holistic and targeted approach to address the complex questions of Xcc-Brassica interactions. Genomic studies revealed that the black rot resistance is a complex trait and is mostly controlled by quantitative trait locus (QTL) with minor effects. Transcriptomic analysis divulged the genes related to photosynthesis, glucosinolate biosynthesis and catabolism, phenylpropanoid biosynthesis pathway, ROS scavenging, calcium signalling, hormonal synthesis and signalling pathway are being differentially expressed upon Xcc infection. Comparative proteomic analysis in relation to susceptible and/or resistance interactions with Xcc identified the involvement of proteins related to photosynthesis, protein biosynthesis, processing and degradation, energy metabolism, innate immunity, redox homeostasis, and defence response and signalling pathways in Xcc-Brassica interaction. Specifically, most of the studies focused on the regulation of the photosynthesis-related proteins as a resistance response in both early and later stages of infection. Metabolomic studies suggested that glucosinolates (GSLs), especially aliphatic and indolic GSLs, its subsequent hydrolysis products, and defensive metabolites synthesized by jasmonic acid (JA)-mediated phenylpropanoid biosynthesis pathway are involved in disease resistance mechanisms against Xcc in Brassica species. Multi-omics analysis showed that JA signalling pathway is regulating resistance against hemibiotrophic pathogen like Xcc. So, the bonhomie between omics technologies and plant breeding is going to trigger major breakthroughs in the field of crop improvement by developing superior cultivars with broad-spectrum resistance. If multi-omics tools are implemented at the right scale, we may be able to achieve the maximum benefits from the minimum. In this review, we have also discussed the challenges, future prospects, and the way forward in the application of omics technologies to accelerate the breeding of B. oleracea for disease resistance. A deeper insight about the current knowledge on omics can offer promising results in the breeding of high-quality disease-resistant crops.
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Affiliation(s)
| | | | | | | | | | | | - Honghui Gu
- Institute of Vegetables, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
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Olawole OI, Liu Q, Chen C, Gleason ML, Beattie GA. The Contributions to Virulence of the Effectors Eop1 and DspE Differ Between Two Clades of Erwinia tracheiphila Strains. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:1399-1408. [PMID: 34505816 DOI: 10.1094/mpmi-06-21-0149-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: 06/13/2023]
Abstract
Strains of Erwinia tracheiphila, causal agent of bacterial wilt of cucurbits, are divided into distinct clades. Et-melo clade strains wilt Cucumis spp. but not Cucurbita spp., thus exhibiting host specificity, whereas Et-C1 clade strains wilt Cucurbita spp. more rapidly than Cucumis melo, thus exhibiting a host preference. This study investigated the contribution of the effector proteins Eop1 and DspE to E. tracheiphila pathogenicity and host adaptation. Loss of eop1 did not enable Et-melo strains to infect squash (Cucurbita pepo) or an Et-C1 strain to induce a more rapid wilt of muskmelon (Cucumis melo), indicating that Eop1 did not function in host specificity or preference as in the related pathogen E. amylovora. However, overexpression of eop1 from Et-melo strain MDCuke but not from Et-C1 strain BHKY increased the virulence of a BHKY eop1 deletion mutant on muskmelon, demonstrating that the Eop1 variants in the two clades are distinct in their virulence functions. Loss of dspE from Et-melo strains reduced but did not eliminate virulence on hosts muskmelon and cucumber, whereas loss of dspE from an Et-C1 strain eliminated pathogenicity on hosts squash, muskmelon, and cucumber. Thus, the centrality of DspE to virulence differs in the two clades. Et-melo mutants lacking the chaperone DspF exhibited similar virulence to mutants lacking DspE, indicating that DspF is the sole chaperone for DspE in E. tracheiphila, unlike in E. amylovora. Collectively, these results provide the first functional evaluation of effectors in E. tracheiphila and demonstrate clade-specific differences in the roles of Eop1 and DspE.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
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Affiliation(s)
- Olakunle I Olawole
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, U.S.A
| | - Qian Liu
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, U.S.A
| | - Chiliang Chen
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, U.S.A
| | - Mark L Gleason
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, U.S.A
| | - Gwyn A Beattie
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, U.S.A
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Mullens A, Jamann TM. Colonization and Movement of Green Fluorescent Protein-Labeled Clavibacter nebraskensis in Maize. PLANT DISEASE 2021; 105:1422-1431. [PMID: 33190611 DOI: 10.1094/pdis-08-20-1823-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Clavibacter nebraskensis causes Goss's bacterial wilt and leaf blight, a major disease of maize. Infected crop residue is the primary inoculum source and infection can occur via wounds or natural openings, such as stomata or hydathodes. The use of resistant hybrids is the primary control method for Goss's wilt. In this study, colonization and movement patterns of C. nebraskensis during infection were examined using green fluorescent protein (GFP)-labeled bacterial strains. We successfully introduced a plasmid to C. nebraskensis via electroporation, which resulted in GFP accumulation. Fluorescence microscopy revealed that in the absence of wounding, bacteria colonize leaf tissue via entry through the hydathodes when guttation droplets are present. Stomatal penetration was not observed under natural conditions. Bacteria initially colonize the xylem and subsequently the mesophyll, which creates the freckles that are characteristic of the disease. Bacteria infiltrated into the mesophyll did not cause disease symptoms, could not enter the vasculature, and did not spread from the initial inoculation point. Bacteria were observed exuding through stomata onto the leaf surface, resulting in the characteristic sheen of diseased leaves. Resistant maize lines exhibited decreased bacterial spread in the vasculature and the mesophyll. These tools to examine C. nebraskensis movement offer opportunities and new insights into the pathogenesis process and can form the basis for improved Goss's wilt management through host resistance.
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Affiliation(s)
- Alexander Mullens
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801
| | - Tiffany M Jamann
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801
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Kashyap A, Planas-Marquès M, Capellades M, Valls M, Coll NS. Blocking intruders: inducible physico-chemical barriers against plant vascular wilt pathogens. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:184-198. [PMID: 32976552 PMCID: PMC7853604 DOI: 10.1093/jxb/eraa444] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/16/2020] [Indexed: 05/20/2023]
Abstract
Xylem vascular wilt pathogens cause devastating diseases in plants. Proliferation of these pathogens in the xylem causes massive disruption of water and mineral transport, resulting in severe wilting and death of the infected plants. Upon reaching the xylem vascular tissue, these pathogens multiply profusely, spreading vertically within the xylem sap, and horizontally between vessels and to the surrounding tissues. Plant resistance to these pathogens is very complex. One of the most effective defense responses in resistant plants is the formation of physico-chemical barriers in the xylem tissue. Vertical spread within the vessel lumen is restricted by structural barriers, namely, tyloses and gels. Horizontal spread to the apoplast and surrounding healthy vessels and tissues is prevented by vascular coating of the colonized vessels with lignin and suberin. Both vertical and horizontal barriers compartmentalize the pathogen at the infection site and contribute to their elimination. Induction of these defenses are tightly coordinated, both temporally and spatially, to avoid detrimental consequences such as cavitation and embolism. We discuss current knowledge on mechanisms underlying plant-inducible structural barriers against major xylem-colonizing pathogens. This knowledge may be applied to engineer metabolic pathways of vascular coating compounds in specific cells, to produce plants resistant towards xylem colonizers.
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Affiliation(s)
- Anurag Kashyap
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Spain
| | - Marc Planas-Marquès
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Spain
| | | | - Marc Valls
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Spain
- Genetics Department, Universitat de Barcelona, Barcelona, Spain
| | - Núria S Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Spain
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14
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Soldan R, Sanguankiattichai N, Bach-Pages M, Bervoets I, Huang WE, Preston GM. From macro to micro: a combined bioluminescence-fluorescence approach to monitor bacterial localization. Environ Microbiol 2021; 23:2070-2085. [PMID: 33103833 PMCID: PMC8614114 DOI: 10.1111/1462-2920.15296] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 01/13/2023]
Abstract
Bacterial bioluminescence is widely used to study the spatiotemporal dynamics of bacterial populations and gene expression in vivo at a population level but cannot easily be used to study bacterial activity at the level of individual cells. In this study, we describe the development of a new library of mini‐Tn7‐lux and lux::eyfp reporter constructs that provide a wide range of lux expression levels, and which combine the advantages of both bacterial bioluminescence and fluorescent proteins to bridge the gap between macro‐ and micro‐scale imaging techniques. We demonstrate that a dual bioluminescence‐fluorescence approach using the lux operon and eYFP can be used to monitor bacterial movement in plants both macro‐ and microscopically and demonstrate that Pseudomonas syringae pv phaseolicola can colonize the leaf vascular system and systemically infect leaves of common bean (Phaseolus vulgaris). We also show that bacterial bioluminescence can be used to study the impact of plant immune responses on bacterial multiplication, viability and spread within plant tissues. The constructs and approach described in this study can be used to study the spatiotemporal dynamics of bacterial colonization and to link population dynamics and cellular interactions in a wide range of biological contexts.
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Affiliation(s)
- Riccardo Soldan
- Department of Plant Sciences, University of Oxford, Oxford, UK
| | | | | | - Indra Bervoets
- Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Wei E Huang
- Department of Engineering, University of Oxford, Oxford, UK
| | - Gail M Preston
- Department of Plant Sciences, University of Oxford, Oxford, UK
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15
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Wielkopolan B, Jakubowska M, Obrępalska-Stęplowska A. Beetles as Plant Pathogen Vectors. FRONTIERS IN PLANT SCIENCE 2021; 12:748093. [PMID: 34721475 PMCID: PMC8549695 DOI: 10.3389/fpls.2021.748093] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/15/2021] [Indexed: 05/16/2023]
Abstract
Herbivorous insects, likewise, other organisms, are exposed to diverse communities of microbes from the surrounding environment. Insects and microorganisms associated with them share a range of relationships, including symbiotic and pathogenic. Insects damage plants by feeding on them and delivering plant pathogens to wounded places, from where pathogens spread over the plant. Thus insects can be considered as both pests and reservoirs or vectors of plant pathogens. Although beetles are not mentioned in the first place as plant pathogen vectors, their transmission of pathogens also takes place and affects the ecosystem. Here we present an overview of beetles as vectors of plant pathogens, including viruses, bacteria, fungi, nematodes, and Oomycota, which are responsible for developing plant diseases that can have a significant impact on crop yield and quality.
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Affiliation(s)
- Beata Wielkopolan
- Department of Monitoring and Signaling of Agrophages, Institute of Plant Protection – National Research Institute, Poznań, Poland
| | - Magdalena Jakubowska
- Department of Monitoring and Signaling of Agrophages, Institute of Plant Protection – National Research Institute, Poznań, Poland
| | - Aleksandra Obrępalska-Stęplowska
- Department of Molecular Biology and Biotechnology, Institute of Plant Protection – National Research Institute, Poznań, Poland
- *Correspondence: Aleksandra Obrępalska-Stęplowska,
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16
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Rocha J, Shapiro LR, Kolter R. A horizontally acquired expansin gene increases virulence of the emerging plant pathogen Erwinia tracheiphila. Sci Rep 2020; 10:21743. [PMID: 33303810 PMCID: PMC7729394 DOI: 10.1038/s41598-020-78157-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022] Open
Abstract
Erwinia tracheiphila is a bacterial plant pathogen that causes a fatal wilt infection in some cucurbit crop plants. Wilt symptoms are thought to be caused by systemic bacterial colonization through xylem that impedes sap flow. However, the genetic determinants of within-plant movement are unknown for this pathogen species. Here, we find that E. tracheiphila has horizontally acquired an operon with a microbial expansin (exlx) gene adjacent to a glycoside hydrolase family 5 (gh5) gene. Plant inoculation experiments with deletion mutants in the individual genes (Δexlx and Δgh5) and the full operon (Δexlx-gh5) resulted in decreased severity of wilt symptoms, decreased mortality rate, and impaired systemic colonization compared to the Wt strain. Co-inoculation experiments with Wt and Δexlx-gh5 rescued the movement defect of the mutant strain, suggesting that expansin and GH5 function extracellularly. Together, these results show that expansin-GH5 contributes to systemic movement through xylem, leading to rapid wilt symptom development and higher rates of plant death. The presence of expansin genes in diverse species of bacterial and fungal wilt-inducing pathogens suggests that microbial expansin proteins may be an under-appreciated virulence factor for many pathogen species.
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Affiliation(s)
- Jorge Rocha
- Department of Microbiology, Harvard Medical School, Boston, MA, USA.
- Conacyt-Centro de Investigación y Desarrollo en Agrobiotecnología Alimentaria, San Agustin Tlaxiaca, 42163, Hidalgo, Mexico.
| | - Lori R Shapiro
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Roberto Kolter
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
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17
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Narváez-Barragán DA, Tovar-Herrera OE, Segovia L, Serrano M, Martinez-Anaya C. Expansin-related proteins: biology, microbe-plant interactions and associated plant-defense responses. MICROBIOLOGY-SGM 2020; 166:1007-1018. [PMID: 33141007 DOI: 10.1099/mic.0.000984] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Expansins, cerato-platanins and swollenins (which we will henceforth refer to as expansin-related proteins) are a group of microbial proteins involved in microbe-plant interactions. Although they share very low sequence similarity, some of their composing domains are near-identical at the structural level. Expansin-related proteins have their target in the plant cell wall, in which they act through a non-enzymatic, but still uncharacterized, mechanism. In most cases, mutagenesis of expansin-related genes affects plant colonization or plant pathogenesis of different bacterial and fungal species, and thus, in many cases they are considered virulence factors. Additionally, plant treatment with expansin-related proteins activate several plant defenses resulting in the priming and protection towards subsequent pathogen encounters. Plant-defence responses induced by these proteins are reminiscent of pattern-triggered immunity or hypersensitive response in some cases. Plant immunity to expansin-related proteins could be caused by the following: (i) protein detection by specific host-cell receptors, (ii) alterations to the cell-wall-barrier properties sensed by the host, (iii) displacement of cell-wall polysaccharides detected by the host. Expansin-related proteins may also target polysaccharides on the wall of the microbes that produced them under certain physiological instances. Here, we review biochemical, evolutionary and biological aspects of these relatively understudied proteins and different immune responses they induce in plant hosts.
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Affiliation(s)
- Delia A Narváez-Barragán
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62110 Cuernavaca Morelos, Mexico
| | - Omar E Tovar-Herrera
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Marcus Family Campus, BeerSheva, Israel
| | - Lorenzo Segovia
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62110 Cuernavaca Morelos, Mexico
| | - Mario Serrano
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, 62110 Cuernavaca Morelos, Mexico
| | - Claudia Martinez-Anaya
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62110 Cuernavaca Morelos, Mexico
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18
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Zhang J, Coaker G, Zhou JM, Dong X. Plant Immune Mechanisms: From Reductionistic to Holistic Points of View. MOLECULAR PLANT 2020; 13:1358-1378. [PMID: 32916334 PMCID: PMC7541739 DOI: 10.1016/j.molp.2020.09.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/05/2020] [Accepted: 09/08/2020] [Indexed: 05/19/2023]
Abstract
After three decades of the amazing progress made on molecular studies of plant-microbe interactions (MPMI), we have begun to ask ourselves "what are the major questions still remaining?" as if the puzzle has only a few pieces missing. Such an exercise has ultimately led to the realization that we still have many more questions than answers. Therefore, it would be an impossible task for us to project a coherent "big picture" of the MPMI field in a single review. Instead, we provide our opinions on where we would like to go in our research as an invitation to the community to join us in this exploration of new MPMI frontiers.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Biotic Interactions, College of Advanced Agricutural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gitta Coaker
- Department of Plant Pathology, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Jian-Min Zhou
- CAS Center for Excellence in Biotic Interactions, College of Advanced Agricutural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xinnian Dong
- Howard Hughes Medical Institute, Duke University, Durham, NC 27708, USA; Department of Biology, Duke University, PO Box 90338, Durham, NC 27708, USA.
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19
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Abebe AM, Choi J, Kim Y, Oh CS, Yeam I, Nou IS, Lee JM. Development of diagnostic molecular markers for marker-assisted breeding against bacterial wilt in tomato. BREEDING SCIENCE 2020; 70:462-473. [PMID: 32968349 PMCID: PMC7495205 DOI: 10.1270/jsbbs.20027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/03/2020] [Indexed: 06/11/2023]
Abstract
Bacterial wilt, caused by the Ralstonia pseudosolanacearum species complex, is an important vascular disease that limits tomato production in tropical and subtropical regions. Two major quantitative trait loci (QTL) of bacterial wilt resistance on chromosome 6 (Bwr-6) and 12 (Bwr-12) were previously identified in Solanum lycopersicum 'Hawaii 7996'; however, marker-assisted breeding for bacterial wilt resistance is not well established. To dissect the QTL, six cleaved amplified polymorphic sites (CAPS) and derived CAPS (dCAPS) markers within the Bwr-6 region and one dCAPS marker near Bwr-12 were developed, and resistance levels in 117 tomato cultivars were evaluated. Two markers, RsR6-5 on chromosome 6 and RsR12-1 on chromosome 12, were selected based on the genotypic and phenotypic analysis. The combination of RsR6-5 and RsR12-1 effectively distinguishes resistant and susceptible cultivars. Furthermore, the efficiency of the two markers was validated in the F3 generation derived from the F2 population between E6203 (susceptible) and Hawaii 7998 (resistant). Resistant alleles at both loci led to the resistance to bacterial wilt. These markers will facilitate marker-assisted breeding of tomato resistant to bacterial wilt.
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Affiliation(s)
- Alebel Mekuriaw Abebe
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, South Korea
| | - Jinwoo Choi
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, South Korea
| | - Youngjun Kim
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, South Korea
| | - Chang-Sik Oh
- Department of Horticultural Biotechnology, College of Life Science, Kyung Hee University, Yongin, Gyeonggi-do 17104, South Korea
| | - Inhwa Yeam
- Department of Horticulture and Breeding, Andong National University, Andong, Gyeongbuk, 36729, South Korea
| | - Ill-Sup Nou
- Department of Horticulture, Sunchon National University, Suncheon, Jeonnam 57922, South Korea
| | - Je Min Lee
- Department of Horticultural Science, Kyungpook National University, Daegu 41566, South Korea
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20
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Chase WR, Zhaxybayeva O, Rocha J, Cosgrove DJ, Shapiro LR. Global cellulose biomass, horizontal gene transfers and domain fusions drive microbial expansin evolution. THE NEW PHYTOLOGIST 2020; 226:921-938. [PMID: 31930503 DOI: 10.1111/nph.16428] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 12/19/2019] [Indexed: 05/23/2023]
Abstract
Plants must rearrange the network of complex carbohydrates in their cell walls during normal growth and development. To accomplish this, all plants depend on proteins called expansins that nonenzymatically loosen noncovalent bonding between cellulose microfibrils. Surprisingly, expansin genes have more recently been found in some bacteria and microbial eukaryotes, where their biological functions are largely unknown. Here, we reconstruct a comprehensive phylogeny of microbial expansin genes. We find these genes in all eukaryotic microorganisms that have structural cell wall cellulose, suggesting expansins evolved in ancient marine microorganisms long before the evolution of land plants. We also find expansins in an unexpectedly high diversity of bacteria and fungi that do not have cellulosic cell walls. These bacteria and fungi inhabit varied ecological contexts, mirroring the diversity of terrestrial and aquatic niches where plant and/or algal cellulosic cell walls are present. The microbial expansin phylogeny shows evidence of multiple horizontal gene transfer events within and between bacterial and eukaryotic microbial lineages, which may in part underlie their unusually broad phylogenetic distribution. Overall, expansins are unexpectedly widespread in bacteria and eukaryotes, and the contribution of these genes to microbial ecological interactions with plants and algae has probbaly been underappreciated.
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Affiliation(s)
- William R Chase
- Department of Biology, Pennsylvania State University, University Park, PA, 16801, USA
| | - Olga Zhaxybayeva
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
- Department of Computer Science, Dartmouth College, Hanover, NH, 03755, USA
| | - Jorge Rocha
- Department of Microbiology and Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA, 02115, USA
| | - Daniel J Cosgrove
- Department of Biology, Pennsylvania State University, University Park, PA, 16801, USA
| | - Lori R Shapiro
- Department of Microbiology and Immunology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA, 02115, USA
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21
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Doblas-Ibáñez P, Deng K, Vasquez MF, Giese L, Cobine PA, Kolkman JM, King H, Jamann TM, Balint-Kurti P, De La Fuente L, Nelson RJ, Mackey D, Smith LG. Dominant, Heritable Resistance to Stewart's Wilt in Maize Is Associated with an Enhanced Vascular Defense Response to Infection with Pantoea stewartii. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:1581-1597. [PMID: 31657672 DOI: 10.1094/mpmi-05-19-0129-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Vascular wilt bacteria such as Pantoea stewartii, the causal agent of Stewart's bacterial wilt of maize (SW), are destructive pathogens that are difficult to control. These bacteria colonize the xylem, where they form biofilms that block sap flow leading to characteristic wilting symptoms. Heritable forms of SW resistance exist and are used in maize breeding programs but the underlying genes and mechanisms are mostly unknown. Here, we show that seedlings of maize inbred lines with pan1 mutations are highly resistant to SW. However, current evidence suggests that other genes introgressed along with pan1 are responsible for resistance. Genomic analyses of pan1 lines were used to identify candidate resistance genes. In-depth comparison of P. stewartii interaction with susceptible and resistant maize lines revealed an enhanced vascular defense response in pan1 lines characterized by accumulation of electron-dense materials in xylem conduits visible by electron microscopy. We propose that this vascular defense response restricts P. stewartii spread through the vasculature, reducing both systemic bacterial colonization of the xylem network and consequent wilting. Though apparently unrelated to the resistance phenotype of pan1 lines, we also demonstrate that the effector WtsE is essential for P. stewartii xylem dissemination, show evidence for a nutritional immunity response to P. stewartii that alters xylem sap composition, and present the first analysis of maize transcriptional responses to P. stewartii infection.
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Affiliation(s)
- Paula Doblas-Ibáñez
- Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093, U.S.A
| | - Kaiyue Deng
- Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093, U.S.A
| | - Miguel F Vasquez
- Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093, U.S.A
| | - Laura Giese
- Department of Horticulture and Crop Sciences, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, U.S.A
| | - Judith M Kolkman
- School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, U.S.A
| | - Helen King
- Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093, U.S.A
| | - Tiffany M Jamann
- Department of Crop Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61801, U.S.A
| | - Peter Balint-Kurti
- United States Department of Agriculture-Agricultural Research Service, Plant Science Research Unit, Raleigh, NC 27695, U.S.A. and Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695, U.S.A
| | | | - Rebecca J Nelson
- School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, U.S.A
| | - David Mackey
- Department of Horticulture and Crop Sciences, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Laurie G Smith
- Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093, U.S.A
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22
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Dissecting quantitative resistance to Xanthomonas campestris pv. campestris in leaves of Brassica oleracea by QTL analysis. Sci Rep 2019; 9:2015. [PMID: 30765761 PMCID: PMC6376059 DOI: 10.1038/s41598-019-38527-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 01/02/2019] [Indexed: 12/24/2022] Open
Abstract
Black rot, caused by the bacterium Xanthomonas campestris pv. campestris (Xcc), produces important economic losses in crops of Brassica oleracea worldwide. Resistance to race 1, the most virulent and widespread in B. oleracea, is under quantitative control. Knowledge about the genetics of this resistance would help in designing strategies to control initial stages of invasion and development of the disease. QTL analysis of the resistance in the BolTBDH mapping population was performed. Resistance was measured with five traits related to initial stages of the invasion, success of infection and spread of the pathogen. Four single-trait QTLs of resistance were found, from which one represent novel variation. After performing multi-trait QTL, we concluded that spread of Xcc is related to the size of the leaf. Individuals from the mapping population follow two different strategies to cope with the spread of the disease: reducing lesion size or maintain more area of the leaf photosynthetically active, being more tolerant to Xcc invasion. Mechanisms underlying variation for resistance may be related to different aspects of plant immunity, including the synthesis of glucosinolates and phenolics.
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23
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Jeger M, Bragard C, Candresse T, Chatzivassiliou E, Dehnen-Schmutz K, Gilioli G, Grégoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Winter S, Manceau C, Pautasso M, Caffier D. Pest categorisation of Pantoea stewartii subsp. stewartii. EFSA J 2018; 16:e05356. [PMID: 32625989 PMCID: PMC7009623 DOI: 10.2903/j.efsa.2018.5356] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Following a request from the European Commission, the EFSA Plant Health Panel performed a pest categorisation of Pantoea stewartii subsp. stewartii (hereafter P. s. subsp. stewartii). P. s. subsp. stewartii is a Gram-negative bacterium that causes Stewart's vascular wilt and leaf blight of sweet corn and maize, a disease responsible for serious crop losses throughout the world. The bacterium is endemic to the USA and is now present in Africa, North, Central and South America, Asia and Ukraine. In the EU, it is reported from Italy with a restricted distribution and under eradication. The bacterium is regulated according to Council Directive 2000/29/EC (Annex IIAI) as a harmful organism whose introduction and spread in the EU is banned on seeds of Zea mays. Other reported potential host plants include various species of the family Poaceae, including weeds, rice (Oryza sativa), oat (Avena sativa) and common wheat (Triticum aestivum), as well as jackfruit (Artocarpus heterophyllus), the ornamental Dracaena sanderiana and the palm Bactris gasipaes, but there is uncertainty about whether these are hosts of P. s. subsp. stewartii or of the other subspecies. The pest could enter the EU via host plants for planting (including seed) and via insect vectors from neighbouring countries. Host plants are widely distributed and climatic conditions are conducive in the EU. P. s. subsp. stewartii could spread by movement of host plants for planting (including seeds) and insect vectors. Impacts could occur on maize and rice. Methods to certify pest freedom of maize seeds are available. The main knowledge gaps concern the availability of vectors in the EU, the level of susceptibility of the maize cultivars grown in the EU, the virulence of strains in recent outbreaks, and the host range of the bacterium. The criteria assessed by the Panel for consideration as a potential quarantine pest are met.
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24
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Tancos MA, Lowe‐Power TM, Peritore‐Galve FC, Tran TM, Allen C, Smart CD. Plant-like bacterial expansins play contrasting roles in two tomato vascular pathogens. MOLECULAR PLANT PATHOLOGY 2018; 19:1210-1221. [PMID: 28868644 PMCID: PMC5835177 DOI: 10.1111/mpp.12611] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/04/2017] [Accepted: 08/31/2017] [Indexed: 05/27/2023]
Abstract
Expansin proteins, which loosen plant cell walls, play critical roles in normal plant growth and development. The horizontal acquisition of functional plant-like expansin genes in numerous xylem-colonizing phytopathogenic bacteria suggests that bacterial expansins may also contribute to virulence. To investigate the role of bacterial expansins in plant diseases, we mutated the non-chimeric expansin genes (CmEXLX2 and RsEXLX) of two xylem-inhabiting bacterial pathogens, the Actinobacterium Clavibacter michiganensis ssp. michiganensis (Cmm) and the β-proteobacterium Ralstonia solanacearum (Rs), respectively. The Cmm ΔCmEXLX2 mutant caused increased symptom development on tomato, which was characterized by more rapid wilting, greater vascular necrosis and abundant atypical lesions on distant petioles. This increased disease severity correlated with larger in planta populations of the ΔCmEXLX2 mutant, even though the strains grew as well as the wild-type in vitro. Similarly, when inoculated onto tomato fruit, ΔCmEXLX2 caused significantly larger lesions with larger necrotic centres. In contrast, the Rs ΔRsEXLX mutant showed reduced virulence on tomato following root inoculation, but not following direct petiole inoculation, suggesting that the RsEXLX expansin contributes to early virulence at the root infection stage. Consistent with this finding, ΔRsEXLX attached to tomato seedling roots better than the wild-type Rs, which may prevent mutants from invading the plant's vasculature. These contrasting results demonstrate the diverse roles of non-chimeric bacterial expansins and highlight their importance in plant-bacterial interactions.
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Affiliation(s)
- Matthew A. Tancos
- Plant Pathology and Plant‐Microbe Biology Section, School of Integrative Plant SciencesCornell UniversityGenevaNY 14456USA
- Present address:
Foreign Disease‐Weed Science Research Unit, USDA‐ARSFort DetrickMD 21702USA
| | | | - F. Christopher Peritore‐Galve
- Plant Pathology and Plant‐Microbe Biology Section, School of Integrative Plant SciencesCornell UniversityGenevaNY 14456USA
| | - Tuan M. Tran
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWI 53706USA
- Present address:
School of Biological SciencesNanyang Technological University639798Singapore
| | - Caitilyn Allen
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWI 53706USA
| | - Christine D. Smart
- Plant Pathology and Plant‐Microbe Biology Section, School of Integrative Plant SciencesCornell UniversityGenevaNY 14456USA
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25
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Malafaia CB, Jardelino ACS, Silva AG, de Souza EB, Macedo AJ, Correia MTDS, Silva MV. Effects of Caatinga Plant Extracts in Planktonic Growth and Biofilm Formation in Ralstonia solanacearum. MICROBIAL ECOLOGY 2018; 75:555-561. [PMID: 28920144 DOI: 10.1007/s00248-017-1073-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
This study describes the first antibiofilm and antibacterial screening for plants from Caatinga against Ralstonia solanacearum, a causal agent of bacterial wilt that presents serious difficulties in control. There were prepared 22 aqueous extracts of plants collected in the Vale do Catimbau-PE, Brazil. The potential antibacterial activity was evaluated by absorbance in OD600 and the antibiofilm activity through the crystal violet method, both of them performed in microplate against isolates of R. solanacearum biofilm formers. The results of the screening showed that Jacaranda rugosa presented antimicrobial activity higher than 90%, while Harpochilus neesianus and Myroxylon peruiferum presented antibiofilm activity higher than 50% for all tested isolates. However, Croton heliotropiifolius showed both the activities, being thus very promising for application in the control of this phytopathogen. The search for viable alternatives to the development of new bioactive compounds safe for the environment, humans, and animals from an adverse and scarce environment such as the Caatinga and encouraged us to find plants that produce effective metabolites against phytopathogenic microorganisms. This in vitro screening is important to guide the development of new products in addition to guide research studies of bioactive compounds.
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Affiliation(s)
- Carolina Barbosa Malafaia
- Departamento de Bioquímica, Universidade Federal de Pernambuco (UFPE), Recife, Pernambuco, Brazil.
- Centro de Tecnologias Estratégicas do Nordeste (CETENE), Recife, Pernambuco, Brazil.
| | | | - Alexandre Gomes Silva
- Instituto Nacional do Semiárido, Av. Francisco Lopes de Almeida, Campina Grande, Paraíba, 58434-700, Brazil
| | - Elineide Barbosa de Souza
- Departamento de Biologia/Área de Microbiologia, Universidade Federal Rural de Pernambuco (UFRPE), Recife, Pernambuco, Brazil
| | - Alexandre José Macedo
- Faculdade de Farmácia e Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil
| | | | - Márcia Vanusa Silva
- Departamento de Bioquímica, Universidade Federal de Pernambuco (UFPE), Recife, Pernambuco, Brazil
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Chen H, Kandel PP, Cruz LF, Cobine PA, De La Fuente L. The Major Outer Membrane Protein MopB Is Required for Twitching Movement and Affects Biofilm Formation and Virulence in Two Xylella fastidiosa strains. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:896-905. [PMID: 28800709 DOI: 10.1094/mpmi-07-17-0161-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
MopB is a major outer membrane protein (OMP) in Xylella fastidiosa, a bacterial plant pathogen that causes losses on many economically important crops. Based on in silico analysis, the uncharacterized MopB protein of X. fastidiosa contains a β-barrel structure with an OmpA-like domain and a predicted calcium-binding motif. Here, MopB function was studied by mutational analysis taking advantage of the natural competence of X. fastidiosa. Mutants of mopB were constructed in two different X. fastidiosa strains, the type strain Temecula and the more virulent WM1-1. Deletion of the mopB gene impaired cell-to-cell aggregation, surface attachment, and biofilm formation in both strains. Interestingly, mopB deletion completely abolished twitching motility. Electron microscopy of the bacterial cell surface revealed that mopB deletion eliminated type IV and type I pili formation, potentially caused by destabilization of the outer membrane. Both mopB mutants showed reduced virulence using tobacco (Nicotiana tabacum) as a host under greenhouse conditions. These results suggest that MopB has pleiotropic functions in biofilm formation and twitching motility and is important for virulence of X. fastidiosa.
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Affiliation(s)
- Hongyu Chen
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Prem P Kandel
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Luisa F Cruz
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
| | - Paul A Cobine
- 2 Department of Biological Sciences, Auburn University
| | - Leonardo De La Fuente
- 1 Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, U.S.A.; and
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Ferreira V, Pianzzola MJ, Vilaró FL, Galván GA, Tondo ML, Rodriguez MV, Orellano EG, Valls M, Siri MI. Interspecific Potato Breeding Lines Display Differential Colonization Patterns and Induced Defense Responses after Ralstonia solanacearum Infection. FRONTIERS IN PLANT SCIENCE 2017; 8:1424. [PMID: 28894453 PMCID: PMC5581342 DOI: 10.3389/fpls.2017.01424] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/02/2017] [Indexed: 05/05/2023]
Abstract
Potato (Solanum tuberosum L.) is one of the main hosts of Ralstonia solanacearum, the causative agent of bacterial wilt. This plant pathogen bacteria produce asymptomatic latent infections that promote its global spread, hindering disease control. A potato breeding program is conducted in Uruguay based on the introgression of resistance from the wild native species S. commersonii Dun. Currently, several backcrosses were generated exploiting the high genetic variability of this wild species resulting in advanced interspecific breeding lines with different levels of bacterial wilt resistance. The overall aim of this work was to characterize the interaction of the improved potato germplasm with R. solanacearum. Potato clones with different responses to R. solanacearum were selected, and colonization, dissemination and multiplication patterns after infection were evaluated. A R. solanacearum strain belonging to the phylotype IIB-sequevar 1, with high aggressiveness on potato was genetically modified to constitutively generate fluorescence and luminescence from either the green fluorescence protein gene or lux operon. These reporter strains were used to allow a direct and precise visualization of fluorescent and luminescent cells in plant tissues by confocal microscopy and luminometry. Based on wilting scoring and detection of latent infections, the selected clones were classified as susceptible or tolerant, while no immune-like resistance response was identified. Typical wilting symptoms in susceptible plants were correlated with high concentrations of bacteria in roots and along the stems. Tolerant clones showed a colonization pattern restricted to roots and a limited number of xylem vessels only in the stem base. Results indicate that resistance in potato is achieved through restriction of bacterial invasion and multiplication inside plant tissues, particularly in stems. Tolerant plants were also characterized by induction of anatomical and biochemical changes after R. solanacearum infection, including hyperplasic activity of conductor tissue, tylose production, callose and lignin deposition, and accumulation of reactive oxygen species. This study highlights the potential of the identified tolerant interspecific potato clones as valuable genetic resources for potato-breeding programs and leads to a better understanding of resistance against R. solanacearum in potato.
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Affiliation(s)
- Virginia Ferreira
- Departamento de Biociencias, Facultad de Química, Universidad de la RepúblicaMontevideo, Uruguay
| | - María J. Pianzzola
- Departamento de Biociencias, Facultad de Química, Universidad de la RepúblicaMontevideo, Uruguay
| | | | - Guillermo A. Galván
- Departamento de Producción Vegetal, Centro Regional Sur, Facultad de Agronomía, Universidad de la RepúblicaCanelones, Uruguay
| | - María L. Tondo
- Instituto de Biología Molecular y Celular de Rosario (CONICET-UNR)Rosario, Argentina
- Área Biología Molecular, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de RosarioRosario, Argentina
| | - María V. Rodriguez
- Área Biología Vegetal (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de RosarioRosario, Argentina
| | - Elena G. Orellano
- Instituto de Biología Molecular y Celular de Rosario (CONICET-UNR)Rosario, Argentina
- Área Biología Molecular, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de RosarioRosario, Argentina
| | - Marc Valls
- Center for Research in Agricultural Genomics, CSIC, IRTA, UAB, UBBarcelona, Spain
- Department of Genetics, Universitat de BarcelonaBarcelona, Spain
| | - María I. Siri
- Departamento de Biociencias, Facultad de Química, Universidad de la RepúblicaMontevideo, Uruguay
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Demmig-Adams B, Stewart JJ, Adams WW. Environmental regulation of intrinsic photosynthetic capacity: an integrated view. CURRENT OPINION IN PLANT BIOLOGY 2017; 37:34-41. [PMID: 28410523 DOI: 10.1016/j.pbi.2017.03.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/17/2017] [Accepted: 03/21/2017] [Indexed: 05/13/2023]
Abstract
Environmental modulation of photosynthetic capacity is reviewed in the context of its assessment and its regulation, genetic differences among species and ecotypes, and links to plant stress tolerance and productivity. Modulation of intrinsic photosynthetic capacity matches investment in photosynthetic components to opportunity for CO2 uptake and productivity in specific environments, with exceptionally high rates during particularly narrow windows of opportunity. Response varies among species and ecotypes and should be evaluated on multiple reference bases as well as chloroplast, leaf, and whole plant scales. Photosynthetic capacity, total foliar vascular transport capacity, and plant sink strength are modulated in concert. Switching among alternative target sinks and alternative foliar vascular architectures may provide avenues for co-optimization of productivity and stress tolerance.
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Affiliation(s)
- Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA.
| | - Jared J Stewart
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
| | - William W Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
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Schandry N. A Practical Guide to Visualization and Statistical Analysis of R. solanacearum Infection Data Using R. FRONTIERS IN PLANT SCIENCE 2017; 8:623. [PMID: 28484483 PMCID: PMC5401893 DOI: 10.3389/fpls.2017.00623] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 04/06/2017] [Indexed: 05/11/2023]
Abstract
This paper describes and summarizes approaches for visualization and statistical analysis using data from Ralstonia solanacearum infection experiments based on methods and concepts that are broadly applicable. Members of the R. solanacearum species complex cause bacterial wilt disease. Bacterial wilt is a lethal plant disease and has been studied for over 100 years. During this time various methods to quantify disease and different ways to analyze the generated data have been employed. Here, I aim to provide a general background on three distinct and commonly used measures of disease: the area under the disease progression curve, longitudinal recordings of disease severity and host survival. I will discuss how one can proceed with visualization, statistical analysis, and interpretation using different datasets while revisiting the general concepts of statistical analysis. Datasets and R code to perform all analyses discussed here are included in the supplement.
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Perilla-Henao LM, Casteel CL. Vector-Borne Bacterial Plant Pathogens: Interactions with Hemipteran Insects and Plants. FRONTIERS IN PLANT SCIENCE 2016; 7:1163. [PMID: 27555855 PMCID: PMC4977473 DOI: 10.3389/fpls.2016.01163] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 07/20/2016] [Indexed: 05/22/2023]
Abstract
Hemipteran insects are devastating pests of crops due to their wide host range, rapid reproduction, and ability to transmit numerous plant-infecting pathogens as vectors. While the field of plant-virus-vector interactions has flourished in recent years, plant-bacteria-vector interactions remain poorly understood. Leafhoppers and psyllids are by far the most important vectors of bacterial pathogens, yet there are still significant gaps in our understanding of their feeding behavior, salivary secretions, and plant responses as compared to important viral vectors, such as whiteflies and aphids. Even with an incomplete understanding of plant-bacteria-vector interactions, some common themes have emerged: (1) all known vector-borne bacteria share the ability to propagate in the plant and insect host; (2) particular hemipteran families appear to be incapable of transmitting vector-borne bacteria; (3) all known vector-borne bacteria have highly reduced genomes and coding capacity, resulting in host-dependence; and (4) vector-borne bacteria encode proteins that are essential for colonization of specific hosts, though only a few types of proteins have been investigated. Here, we review the current knowledge on important vector-borne bacterial pathogens, including Xylella fastidiosa, Spiroplasma spp., Liberibacter spp., and 'Candidatus Phytoplasma spp.'. We then highlight recent approaches used in the study of vector-borne bacteria. Finally, we discuss the application of this knowledge for control and future directions that will need to be addressed in the field of vector-plant-bacteria interactions.
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Affiliation(s)
| | - Clare L. Casteel
- Department of Plant Pathology, University of California at Davis, Davis, CAUSA
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