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El Housni Z, Ezrari S, Radouane N, Tahiri A, Ouijja A, Errafii K, Hijri M. Evaluating Rhizobacterial Antagonists for Controlling Cercospora beticola and Promoting Growth in Beta vulgaris. Microorganisms 2024; 12:668. [PMID: 38674613 PMCID: PMC11052011 DOI: 10.3390/microorganisms12040668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/28/2024] Open
Abstract
Cercospora beticola Sacc. is an ascomycete pathogen that causes Cercospora leaf spot in sugar beets (Beta vulgaris L.) and other related crops. It can lead to significant yield losses if not effectively managed. This study aimed to assess rhizosphere bacteria from sugar beet soil as a biological control agent against C. beticola and evaluate their effect on B. vulgaris. Following a dual-culture screening, 18 bacteria exhibiting over 50% inhibition were selected, with 6 of them demonstrating more than 80% control. The bacteria were identified by sequencing the 16S rRNA gene, revealing 12 potential species belonging to 6 genera, including Bacillus, which was represented by 4 species. Additionally, the biochemical and molecular properties of the bacteria were characterized in depth, as well as plant growth promotion. PCR analysis of the genes responsible for producing antifungal metabolites revealed that 83%, 78%, 89%, and 56% of the selected bacteria possessed bacillomycin-, iturin-, fengycin-, and surfactin-encoding genes, respectively. Infrared spectroscopy analysis confirmed the presence of a lipopeptide structure in the bacterial supernatant filtrate. Subsequently, the bacteria were assessed for their effect on sugar beet plants in controlled conditions. The bacteria exhibited notable capabilities, promoting growth in both roots and shoots, resulting in significant increases in root length and weight and shoot length. A field experiment with four bacterial candidates demonstrated good performance against C. beticola compared to the difenoconazole fungicide. These bacteria played a significant role in disease control, achieving a maximum efficacy of 77.42%, slightly below the 88.51% efficacy attained with difenoconazole. Additional field trials are necessary to verify the protective and growth-promoting effects of these candidates, whether applied individually, combined in consortia, or integrated with chemical inputs in sugar beet crop production.
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Affiliation(s)
- Zakariae El Housni
- Laboratory of Biotechnology and Molecular Biology, Department of Biology, Faculty of Science, Moulay Ismail University, Zitoune, Meknès 50050, Morocco; (Z.E.H.); (A.O.)
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, BPS 40, Meknès 50001, Morocco;
| | - Said Ezrari
- Microbiology Unit, Laboratory of Bioresources, Biotechnology, Ethnopharmacology and Health, Faculty of Medicine and Pharmacy Oujda, University Mohammed Premier, P.O. Box 724 Hay Al Quods, Oujda 60000, Morocco;
| | - Nabil Radouane
- African Genome Center, University Mohammed VI Polytechnic (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco; (N.R.); (K.E.)
| | - Abdessalem Tahiri
- Phytopathology Unit, Department of Plant Protection, Ecole Nationale d’Agriculture de Meknès, BPS 40, Meknès 50001, Morocco;
| | - Abderrahman Ouijja
- Laboratory of Biotechnology and Molecular Biology, Department of Biology, Faculty of Science, Moulay Ismail University, Zitoune, Meknès 50050, Morocco; (Z.E.H.); (A.O.)
| | - Khaoula Errafii
- African Genome Center, University Mohammed VI Polytechnic (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco; (N.R.); (K.E.)
| | - Mohamed Hijri
- African Genome Center, University Mohammed VI Polytechnic (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco; (N.R.); (K.E.)
- Institut de Recherche en Biologie Végétale (IRBV), Département de Sciences Biologiques, Université de Montréal, Montréal, QC H1X 2B2, Canada
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Tan W, Li K, Liu D, Xing W. Cercospora leaf spot disease of sugar beet. Plant Signal Behav 2023; 18:2214765. [PMID: 37209061 DOI: 10.1080/15592324.2023.2214765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/30/2023] [Accepted: 05/01/2023] [Indexed: 05/22/2023]
Abstract
Leaf spot disease caused by Cercospora beticola Sacc. is the most damaging foliar disease threatening sugar beet production worldwide. The wide spread of disease incurs a reduction of yield and economic losses. The in-depth knowledge of disease epidemiology and virulence factor of pathogen is crucial and basic for preventing fungal disease. The integrated control strategies are needed for an efficient and sustainable disease management. The rotation of fungicides and crop could reduce the initial inoculum and delay the emergence of resistant pathogens. Spraying fungicides under the guide of forecasting models and molecular detecting techniques may hinder the onset of disease prevalence. The resistant varieties of sugar beet to cercospora leaf spot could be obtained by combining classical and molecular breeding methods. More effective approaches are supposed to develop for prevention and control for fungal disease of sugar beet.
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Affiliation(s)
- Wenbo Tan
- National Beet Medium-term Gene Bank, Heilongjiang University, Harbin, P.R. China
- Key Laboratory of Sugar Beet Genetics and Breeding, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, P.R. China
| | - Kexuan Li
- National Beet Medium-term Gene Bank, Heilongjiang University, Harbin, P.R. China
- Key Laboratory of Sugar Beet Genetics and Breeding, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, P.R. China
| | - Dali Liu
- National Beet Medium-term Gene Bank, Heilongjiang University, Harbin, P.R. China
- Key Laboratory of Sugar Beet Genetics and Breeding, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, P.R. China
| | - Wang Xing
- National Beet Medium-term Gene Bank, Heilongjiang University, Harbin, P.R. China
- Key Laboratory of Sugar Beet Genetics and Breeding, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, P.R. China
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Fugate KK, Khan MFR, Eide JD, Hakk PC, Lafta AM, Qi A. Sugar Beet Root Storage Properties Are Unaffected by Cercospora Leaf Spot. Plant Dis 2023:PDIS09222156RE. [PMID: 36415894 DOI: 10.1094/pdis-09-22-2156-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Cercospora leaf spot (CLS; causal agent Cercospora beticola Sacc.) is endemic in many sugar beet production regions due to the widespread distribution of C. beticola and the inability of current management practices to provide complete control of the disease. Roots harvested from plants with CLS, therefore, are inevitably incorporated into sugar beet root storage piles, even though the effects of CLS on root storage properties are largely unknown. Research was conducted to determine the effects of CLS on storage properties including root respiration rate, sucrose loss, invert sugar accumulation, loss in recoverable sucrose yield, and changes in sucrose loss to molasses with respect to CLS disease severity and storage duration. Roots were obtained from plants with four levels of CLS severity in each of three production years, stored at 5°C and 95% relative humidity for up to 120 days, and evaluated for storage characteristics after 30, 90, and 120 days storage. No significant or repeatable effects of CLS on root respiration rate, sucrose loss, invert sugar accumulation, loss in recoverable sucrose yield, or change in sucrose loss to molasses were detected after 30, 90, or 120 days storage regardless of the severity of CLS disease symptoms. Therefore, no evidence was found that CLS accelerates sugar beet storage losses, and it is concluded that roots harvested from plants with CLS can be stored without additional or specialized precaution, regardless of CLS symptom severity.
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Affiliation(s)
- Karen K Fugate
- Edward T. Schafer Agricultural Research Center, USDA-ARS, Fargo, ND 58102, U.S.A
| | - Mohamad F R Khan
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
- University of Minnesota Extension Service, St. Paul, MN 55108, U.S.A
| | - John D Eide
- Edward T. Schafer Agricultural Research Center, USDA-ARS, Fargo, ND 58102, U.S.A
| | - Peter C Hakk
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
| | - Abbas M Lafta
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
| | - Aiming Qi
- Centre for Agriculture, Food and Environmental Management Research, School of Life and Medical Sciences, University of Hertfordshire, Hatfield AL10 9AB, U.K
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Sehsah MD, El-Kot GA, El-Nogoumy BA, Alorabi M, El-Shehawi AM, Salama NH, El-Tahan AM. Efficacy of Bacillus subtilis, Moringa oleifera seeds extract and potassium bicarbonate on Cercospora leaf spot on sugar beet. Saudi J Biol Sci 2022; 29:2219-2229. [PMID: 35531157 PMCID: PMC9072934 DOI: 10.1016/j.sjbs.2021.11.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 12/22/2022] Open
Abstract
Cercospora leaf spot caused by Cercospora beticola are among the most dangerous plant diseases on sugar beet plants. It causes heavy economic losses, whether on the yield of roots, the percentage of sugar in them, or the quality of sugar produced. In addition to the economic cost caused by chemical control, these chemical pesticides cause an imbalance in the ecosystem and harm the health of humans and animals. In an attempt to search for a safer method than pesticides and environmentally friendly, an evaluation of using biocontrol agents, Bacillus subtilis as cell suspension (108 cell/ml), was conducted in this study. Seeds extract of Moringa oleifera with two concentrations (25 and 50 g/L) and potassium bicarbonate at (5 and10 g/L (compared to fungicide Montoro 30% EC (Propiconazole 15% + Difenoconazole 15%). The evaluation results for twenty-five sugar beet varieties showed a significant discrepancy between these varieties in the extent of their susceptibility to infection with the disease under investigation. In-Vitro, B. subtilis induced an antagonist to C. beticola, and both M. oleifera seeds extract and potassium bicarbonate significantly reduced the linear growth of this pathogen. Under field conditions, the treatments used have given positive results in controlling Cercospora leaf spots. They significantly decreased the severity of disease and prevented C. beticola from creating conidiophores and conidiospores, along with examining their cell walls with the formation of plasmolysis of the fungus cells and reducing both the number and diameter of the spots on the surface leaves; this was demonstrated using a scanning electron microscope (SEM). It is worth noting that the best results obtained were most often when treated with M. oleifera seeds extract, followed by potassium bicarbonate, then cell suspension of B. subtilis. In addition, the percentage of the content of beet roots from total soluble solids and sucrose has improved significantly due to spraying sugar beet plants with the substances mentioned earlier. These treatments also contributed to a significant improvement in the enzymes polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase.
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Affiliation(s)
- Mohamed D. Sehsah
- Maize and Sugar Crops Diseases Research Department, Plant Pathology Research Institution, Agricultural Research Center, Giza, Egypt
| | - Gabr A. El-Kot
- Agriculture Botany Department, Faculty of Agriculture, Kafrelsheikh University, Kafr El-Sheikh 33516, Egypt
| | - Baher A. El-Nogoumy
- Microbiology Department, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh 33516, Egypt
| | - Mohammed Alorabi
- Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
| | - Ahmed M. El-Shehawi
- Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
| | - Nagwa H. Salama
- Maize and Sugar Crops Diseases Research Department, Plant Pathology Research Institution, Agricultural Research Center, Giza, Egypt
| | - Amira M. El-Tahan
- Plant Production Department, Arid Lands Cultivation Research Institute, The City of Scientific Research and Technological Applications, SRTA-City. Borg El Arab, Alexandria, Egypt
- Corresponding author.
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Kumar R, Mazakova J, Ali A, Sur VP, Sen MK, Bolton MD, Manasova M, Rysanek P, Zouhar M. Characterization of the Molecular Mechanisms of Resistance against DMI Fungicides in Cercospora beticola Populations from the Czech Republic. J Fungi (Basel) 2021; 7:1062. [PMID: 34947044 PMCID: PMC8706352 DOI: 10.3390/jof7121062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/20/2022] Open
Abstract
Cercospora leaf spot (CLS), caused by the fungal pathogen Cercospora beticola, is the most important foliar pathogen of sugar beet worldwide. Extensive reliance on fungicides to manage CLS has resulted in the evolution of fungicide resistance in C. beticola worldwide, including populations in the Czech Republic. One important class of fungicides used to manage CLS is the sterol demethylation inhibitors (DMI). The aim of our study was to assess DMI resistance in C. beticola from the Czech Republic and elucidate the molecular basis of DMI resistance in this population. A total of 50 isolates were collected in 2018 and 2019 from the major sugar beet growing regions of the Czech Republic and assessed for in vitro sensitivity to the DMI fungicides propiconazole, prochloraz, and epoxiconazole. These analyses identified three strains that exhibited 50% effective concentration (EC50) values > 1.0 μg mL-1 against respective fungicides, which were therefore considered resistant. In contrast, strains that exhibited lowest EC50 values were considered sensitive. To explore the molecular basis of resistance in these three strains, the cytochrome P450-dependent sterol 14α-demethylase (Cyp51) gene was sequenced. Sequence analysis identified a Y464S mutation in all three resistant strains. To assess whether Cyp51 gene expression may play a role in DMI resistance, selected strains were grown in vitro with and without fungicide treatment. These analyses indicated that Cyp51 gene expression was significantly induced after fungicide treatment. Thus, we conclude that Y464S point mutation along with induced Cyp51 gene overexpression is likely responsible for resistance against DMI fungicides in C. beticola from the Czech Republic.
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Affiliation(s)
- Ram Kumar
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
| | - Jana Mazakova
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
| | - Asad Ali
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
| | - Vishma Pratap Sur
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic;
| | - Madhab Kumar Sen
- Department of Agroecology and Crop Production, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic;
| | - Melvin D. Bolton
- Northern Crop Science Laboratory, United States Department of Agriculture, 1307 18th St N, Fargo, ND 58102, USA;
| | - Marie Manasova
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
| | - Pavel Rysanek
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
| | - Miloslav Zouhar
- Department of Plant Protection, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic; (R.K.); (J.M.); (A.A.); (M.M.); (P.R.)
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Li Y, Zhou M, Yang Y, Liu Q, Zhang Z, Han C, Wang Y. Characterization of the Mycovirome from the Plant-Pathogenic Fungus Cercospora beticola. Viruses 2021; 13:1915. [PMID: 34696345 DOI: 10.3390/v13101915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/16/2021] [Accepted: 09/19/2021] [Indexed: 12/25/2022] Open
Abstract
Cercospora leaf spot (CLS) caused by Cercospora beticola is a devastating foliar disease of sugar beet (Beta vulgaris), resulting in high yield losses worldwide. Mycoviruses are widespread fungi viruses and can be used as a potential biocontrol agent for fugal disease management. To determine the presence of mycoviruses in C. beticola, high-throughput sequencing analysis was used to determine the diversity of mycoviruses in 139 C. beticola isolates collected from major sugar beet production areas in China. The high-throughput sequencing reads were assembled and searched against the NCBI database using BLASTn and BLASTx. The results showed that the obtained 93 contigs were derived from eight novel mycoviruses, which were grouped into 3 distinct lineages, belonging to the families Hypoviridae, Narnaviridae and Botourmiaviridae, as well as some unclassified (−)ssRNA viruses in the order Bunyavirales and Mononegavirales. To the best of our knowledge, this is the first identification of highly diverse mycoviruses in C. beticola. The novel mycoviruses explored in this study will provide new viral materials to biocontrol Cercospora diseases. Future studies of these mycoviruses will aim to assess the roles of each mycovirus in biological function of C. beticola in the future.
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El Jarroudi M, Chairi F, Kouadio L, Antoons K, Sallah AHM, Fettweis X. Weather-Based Predictive Modeling of Cercospora beticola Infection Events in Sugar Beet in Belgium. J Fungi (Basel) 2021; 7:jof7090777. [PMID: 34575815 PMCID: PMC8470031 DOI: 10.3390/jof7090777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/08/2021] [Accepted: 09/17/2021] [Indexed: 11/16/2022] Open
Abstract
Cercospora leaf spot (CLS; caused by Cercospora beticola Sacc.) is the most widespread and damaging foliar disease of sugar beet. Early assessments of CLS risk are thus pivotal to the success of disease management and farm profitability. In this study, we propose a weather-based modelling approach for predicting infection by C. beticola in sugar beet fields in Belgium. Based on reported weather conditions favoring CLS epidemics and the climate patterns across Belgian sugar beet-growing regions during the critical infection period (June to August), optimum weather conditions conducive to CLS were first identified. Subsequently, 14 models differing according to the combined thresholds of air temperature (T), relative humidity (RH), and rainfall (R) being met simultaneously over uninterrupted hours were evaluated using data collected during the 2018 to 2020 cropping seasons at 13 different sites. Individual model performance was based on the probability of detection (POD), the critical success index (CSI), and the false alarm ratio (FAR). Three models (i.e., M1, M2 and M3) were outstanding in the testing phase of all models. They exhibited similar performance in predicting CLS infection events at the study sites in the independent validation phase; in most cases, the POD, CSI, and FAR values were ≥84%, ≥78%, and ≤15%, respectively. Thus, a combination of uninterrupted rainy conditions during the four hours preceding a likely start of an infection event, RH > 90% during the first four hours and RH > 60% during the following 9 h, daytime T > 16 °C and nighttime T > 10 °C, were the most conducive to CLS development. Integrating such weather-based models within a decision support tool determining fungicide spray application can be a sound basis to protect sugar beet plants against C. beticola, while ensuring fungicides are applied only when needed throughout the season.
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Affiliation(s)
- Moussa El Jarroudi
- Water, Environment and Development Unit, Department of Environmental Sciences and Management, UR SPHERES, University of Liège, 6700 Arlon, Belgium; (F.C.); (A.-H.M.S.)
- Correspondence: ; Tel.: +32-63-230967
| | - Fadia Chairi
- Water, Environment and Development Unit, Department of Environmental Sciences and Management, UR SPHERES, University of Liège, 6700 Arlon, Belgium; (F.C.); (A.-H.M.S.)
| | - Louis Kouadio
- Centre for Applied Climate Sciences, University of Southern Queensland, Toowoomba, QLD 4350, Australia;
| | - Kathleen Antoons
- Institut Royal Belge pour l’Amélioration de la Betterave, 3300 Tirlemont, Belgium;
| | - Abdoul-Hamid Mohamed Sallah
- Water, Environment and Development Unit, Department of Environmental Sciences and Management, UR SPHERES, University of Liège, 6700 Arlon, Belgium; (F.C.); (A.-H.M.S.)
| | - Xavier Fettweis
- Laboratory of Climatology, Department of Geography, UR SPHERES, University of Liège, 4000 Liège, Belgium;
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Muellender MM, Mahlein AK, Stammler G, Varrelmann M. Evidence for the association of target-site resistance in cyp51 with reduced DMI sensitivity in European Cercospora beticola field isolates. Pest Manag Sci 2021; 77:1765-1774. [PMID: 33236506 DOI: 10.1002/ps.6197] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 11/10/2020] [Accepted: 11/24/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Cercospora leaf spot caused by Cercospora beticola is the most relevant foliar disease in sugar beet cultivation. In the last decade a decreasing sensitivity of C. beticola towards demethylation inhibitors (DMIs) occurred. Different mechanisms mediating a reduced sensitivity towards DMIs have been identified in different plant pathogens to date, such as target site mutations, over-expression or active excretion of the fungicide. RESULTS A sequencing of the cytochrome P450-dependent sterol 14α-demethylase gene sequence (cyp51) of diverse C. beticola isolates collected in different European countries with reduced DMI sensitivity was performed in order to find a possible correlation of mutations with higher EC50 values. The amino acid alterations Y464S, L144F and I309T combined with L144F were found to be associated with a reduced sensitivity. Furthermore, mutations I387M, M145W and M145W with E460Q were found uniquely. Additionally, constitutive and fungicide triggered expression of cyp51 was assayed by means of RT-qPCR. A very strong induction of cyp51 mRNA expression in sensitive isolates suggests that the fungal cells upregulate expression to maintain ergosterol biosynthesis in DMI presence. The less intensive cyp51 induction in isolates with higher EC50 values underlines the possible correlation of the found target-site mutations with reduced sensitivity. CONCLUSION This study provides new results about possible alterations in the target gene mediating reduced sensitivity of C. beticola towards DMIs and hypothesized a fungicide induced over-expression of the target enzyme CYP51 as natural reaction of the fungus to fungicide application. © 2020 Society of Chemical Industry.
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Shrestha S, Neubauer J, Spanner R, Natwick M, Rios J, Metz N, Secor GA, Bolton MD. Rapid Detection of Cercospora beticola in Sugar Beet and Mutations Associated with Fungicide Resistance Using LAMP or Probe-Based qPCR. Plant Dis 2020; 104:1654-1661. [PMID: 32282278 DOI: 10.1094/pdis-09-19-2023-re] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Cercospora leaf spot (CLS), caused by the fungal pathogen Cercospora beticola, is the most destructive disease of sugar beet worldwide. Although growing CLS-tolerant varieties is helpful, disease management currently requires timely application of fungicides. However, overreliance on fungicides has led to the emergence of fungicide resistance in many C. beticola populations, resulting in multiple epidemics in recent years. Therefore, this study focused on developing a fungicide resistance detection "toolbox" for early detection of C. beticola in sugar beet leaves and mutations associated with different fungicides in the pathogen population. A loop-mediated isothermal amplification (LAMP) method was developed for rapid detection of C. beticola in infected sugar beet leaves. The LAMP primers specific to C. beticola (Cb-LAMP) assay was able to detect C. beticola in inoculated sugar beet leaves as early as 1 day postinoculation. A quinone outside inhibitor (QoI)-LAMP assay was also developed to detect the G143A mutation in cytochrome b associated with QoI resistance in C. beticola. The assay detected the mutation in C. beticola both in vitro and in planta with 100% accuracy. We also developed a probe-based quantitative PCR (qPCR) assay for detecting an E198A mutation in β-tubulin associated with benzimidazole resistance and a probe-based qPCR assay for detection of mutations in cytochrome P450-dependent sterol 14α-demethylase (Cyp51) associated with resistance to sterol demethylation inhibitor fungicides. The primers and probes used in the assay were highly efficient and precise in differentiating the corresponding fungicide-resistant mutants from sensitive wild-type isolates.
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Affiliation(s)
- Subidhya Shrestha
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Jonathan Neubauer
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Rebecca Spanner
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Mari Natwick
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Joshua Rios
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Nicholas Metz
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
| | - Gary A Secor
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
| | - Melvin D Bolton
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58108, U.S.A
- United States Department of Agriculture-Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58102, U.S.A
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Dölfors F, Holmquist L, Dixelius C, Tzelepis G. A LysM effector protein from the basidiomycete Rhizoctonia solani contributes to virulence through suppression of chitin-triggered immunity. Mol Genet Genomics 2019; 294:1211-8. [PMID: 31076860 DOI: 10.1007/s00438-019-01573-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/29/2019] [Indexed: 12/31/2022]
Abstract
Rhizoctonia solani is a fungal species that belongs to the fungal division Basidiomycota. It is a soil-borne pathogen that attacks a broad range of plant species and crops. Disease symptoms are commonly seen as damping off of seedlings and root rot, although it can infect plants at any developmental stage. Despite the severity of this disease, many aspects in R. solani infection biology remain unclear. Here we investigated the role of a LysM effector, previously predicted from the genome of a R. solani AG2-2IIIB strain that has sugar beet as a host. Gene expression analysis showed that RsLysM was highly induced upon sugar beet infection. When RsLysM was heterologously expressed in Cercospora beticola, necrotic lesion size and fungal colonization ability were increased, indicating a role in virulence. RsLysM displayed chitin-binding affinity and suppression of chitin-triggered immunity but could not protect hyphae from hydrolysis. Overall, this study is the first characterization of a LysM effector from Basidiomycota, suggesting that this necrotrophic fungal species relies on perturbation of chitin-triggered immunity to establish a successful infection.
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Vogel J, Kenter C, Holst C, Märländer B. New Generation of Resistant Sugar Beet Varieties for Advanced Integrated Management of Cercospora Leaf Spot in Central Europe. Front Plant Sci 2018; 9:222. [PMID: 29535743 PMCID: PMC5835311 DOI: 10.3389/fpls.2018.00222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/05/2018] [Indexed: 05/23/2023]
Abstract
Cercospora leaf spot (CLS) epidemics in sugar beet have been increasing in recent years causing higher use of fungicides. Concomitantly, the availability of effective fungicides is at risk because of resistance development in the fungus, the lack of new active ingredients as well as restrictive approval practices. A key option for an integrated management of CLS is cultivation of resistant varieties. Because of the yield penalty in resistant varieties, acceptance in commercial practice so far has been low. The aim of our study was to characterize recent sugar beet varieties registered in Germany in terms of resistance and tolerance to CLS and their value for integrated pest management. The genetic basis of CLS resistance in varieties is protected by intellectual property rights even after variety registration and not open to the public due to economic competition. To gain reliable data for cultivation, varieties have to be tested for their resistance traits under field conditions at varying levels of infection with Cercospora beticola. In collaboration with variety related stakeholders, 15 sugar beet varieties were tested in 49 field trials in Germany from 2014 to 2016 for their yield response to CLS. The trials were set up in a split-plot design with and without infection (i.e., with and without fungicide). The classification of varietal reaction to CLS is based on symptomatic leaf area (susceptibility) and the resulting relative yield loss (tolerance). Since the relation between both parameters varied among varieties, it was used as an additional parameter to describe tolerance. On this basis, three groups of varieties were identified. They can be characterized as a susceptible, a resistant and a presumably tolerant cluster. A comparison of the data with an older dataset originating from 2009 to 2011 revealed that yield performance of recent varieties with resistance to C. beticola caught up with susceptible varieties due to breeding progress. They showed no yield penalty in the absence of the disease and better economic performance than susceptible varieties. It is assumed that these varieties will allow a substantial reduction of fungicide use for an advanced integrated pest management under central European conditions.
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Affiliation(s)
- Johannes Vogel
- Institute of Sugar Beet Research at the University of Göttingen, Göttingen, Germany
- Department of Agricultural Economics and Rural Development, University of Göttingen, Göttingen, Germany
| | - Christine Kenter
- Institute of Sugar Beet Research at the University of Göttingen, Göttingen, Germany
| | - Carsten Holst
- Department of Agricultural Economics and Rural Development, University of Göttingen, Göttingen, Germany
| | - Bernward Märländer
- Institute of Sugar Beet Research at the University of Göttingen, Göttingen, Germany
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Schmittgen S, Metzner R, Van Dusschoten D, Jansen M, Fiorani F, Jahnke S, Rascher U, Schurr U. Magnetic resonance imaging of sugar beet taproots in soil reveals growth reduction and morphological changes during foliar Cercospora beticola infestation. J Exp Bot 2015; 66:5543-53. [PMID: 25873673 PMCID: PMC4585413 DOI: 10.1093/jxb/erv109] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Cercospora leaf spot (CLS) infection can cause severe yield loss in sugar beet. Introduction of Cercospora-resistant varieties in breeding programmes is important for plant protection to reduce both fungicide applications and the risk of the development of fungal resistance. However, in vivo monitoring of the sugar-containing taproots at early stages of foliar symptoms and the characterization of the temporal development of disease progression has proven difficult. Non-invasive magnetic resonance imaging (MRI) measurements were conducted to quantify taproot development of genotypes with high (HS) and low (LS) levels of susceptibility after foliar Cercospora inoculation. Fourteen days post-inoculation (dpi) the ratio of infected leaf area was still low (~7%) in both the HS and LS genotypes. However, during this period, the volumetric growth of the taproot had already started to decrease. Additionally, inoculated plants showed a reduction of the increase in width of inner cambial rings while the width of outer rings increased slightly compared with non-inoculated plants. This response partly compensated for the reduced development of inner rings that had a vascular connection with Cercospora-inoculated leaves. Hence, alterations in taproot anatomical features such as volume and cambial ring development can be non-invasively detected already at 14 dpi, providing information on the early impact of the infection on whole-plant performance. All these findings show that MRI is a suitable tool to identify promising candidate parent lines with improved resistance to Cercospora, for example with comparatively lower taproot growth reduction at early stages of canopy infection, for future introduction into breeing programmes.
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Affiliation(s)
- Simone Schmittgen
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Ralf Metzner
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Dagmar Van Dusschoten
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Marcus Jansen
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Fabio Fiorani
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Siegfried Jahnke
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Uwe Rascher
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
| | - Ulrich Schurr
- Forschungszentrum Jülich GmbH, Institut für Bio-und Geowissenschaften, IBG-2: Plant Sciences, Wilhelm-Johnen-Straße, D-52425 Jülich, Germany
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Bergsträsser S, Fanourakis D, Schmittgen S, Cendrero-Mateo MP, Jansen M, Scharr H, Rascher U. HyperART: non-invasive quantification of leaf traits using hyperspectral absorption-reflectance-transmittance imaging. Plant Methods 2015; 11:1. [PMID: 25649124 PMCID: PMC4302522 DOI: 10.1186/s13007-015-0043-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 01/03/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND Combined assessment of leaf reflectance and transmittance is currently limited to spot (point) measurements. This study introduces a tailor-made hyperspectral absorption-reflectance-transmittance imaging (HyperART) system, yielding a non-invasive determination of both reflectance and transmittance of the whole leaf. We addressed its applicability for analysing plant traits, i.e. assessing Cercospora beticola disease severity or leaf chlorophyll content. To test the accuracy of the obtained data, these were compared with reflectance and transmittance measurements of selected leaves acquired by the point spectroradiometer ASD FieldSpec, equipped with the FluoWat device. RESULTS The working principle of the HyperART system relies on the upward redirection of transmitted and reflected light (range of 400 to 2500 nm) of a plant sample towards two line scanners. By using both the reflectance and transmittance image, an image of leaf absorption can be calculated. The comparison with the dynamically high-resolution ASD FieldSpec data showed good correlation, underlying the accuracy of the HyperART system. Our experiments showed that variation in both leaf chlorophyll content of four different crop species, due to different fertilization regimes during growth, and fungal symptoms on sugar beet leaves could be accurately estimated and monitored. The use of leaf reflectance and transmittance, as well as their sum (by which the non-absorbed radiation is calculated) obtained by the HyperART system gave considerably improved results in classification of Cercospora leaf spot disease and determination of chlorophyll content. CONCLUSIONS The HyperART system offers the possibility for non-invasive and accurate mapping of leaf transmittance and absorption, significantly expanding the applicability of reflectance, based on mapping spectroscopy, in plant sciences. Therefore, the HyperART system may be readily employed for non-invasive determination of the spatio-temporal dynamics of various plant properties.
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Affiliation(s)
- Sergej Bergsträsser
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Dimitrios Fanourakis
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- />Present address: Department of Crop Science, Technological Educational Institute of Crete, GR 71004 Heraklio, Greece
- />Present address: Institute of Viticulture, Floriculture and Vegetable Crops, Hellenic Agricultural Organization ‘Demeter’ (NAGREF), P.O. Box 2228, GR 71003 Heraklio, Greece
| | - Simone Schmittgen
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Maria Pilar Cendrero-Mateo
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Marcus Jansen
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- />Present address: LemnaTec GmbH, Pascalstraße 59, 52076 Aachen, Germany
| | - Hanno Scharr
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Uwe Rascher
- />Institute for Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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