Sharp eyespot(Rhizoctonia cerealis)is a widespread soil-borne fungal disease that poses a severe threat to wheat health,and it is one of the main obstacles to achieving stable and high-quality wheat yields in China.Ou...Sharp eyespot(Rhizoctonia cerealis)is a widespread soil-borne fungal disease that poses a severe threat to wheat health,and it is one of the main obstacles to achieving stable and high-quality wheat yields in China.Our collaborative team has developed a novel,efficient,and low-toxicity fungicide named Y17991(N-(2-(2,4-bis-(trifluoromethyl)phenoxy)phenyl)-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide).Preliminary laboratory tests confirmed the significant inhibitory effect of this agent on R.cerealis.Large-area field trials also demonstrated its efficacy,with a disease prevention index of 83.52%,which is 1.97%greater than that of the widely used thifluzamide,and it significantly increased the wheat yield.Moreover,this study explored the impacts of Y17991 on the structure and function of the microbial community in wheat rhizosphere soil.Bacterial communities were more strongly affected than fungal communities.Y17991 significantly modulated key amino acid metabolic pathways and certain biosynthetic processes in diseased wheat rhizospheres,and it also enhanced certain biosynthetic pathways and metabolic activities in healthy wheat rhizospheres.Additionally,the application of Y17991 regulated rhizosphere metabolites,thus exerting significant control over the microbial community.We identified 15 microbial strains potentially involved in the prevention and treatment of R.cerealis,and Y17991 treatment promoted the growth of Pedobacter and Bacillus strains.These strains not only aid in plant growth but they also have the potential for disease prevention.In summary,Y17991 application at a reasonable dose does not cause significant disruption to nontarget rhizosphere microbial communities.In future studies,we will continue to investigate the impacts of Y17991 on nonmicrobial components in soil ecosystems,such as protozoa and nematodes.Our research provides a theoretical basis for the scientific application and promotion of new fungicides and offers a significant reference for establishing a comprehensive system for assessing the ecological impact of pesticides on the environment.展开更多
The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent stra...The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.展开更多
Fusarium crown rot(FCR) and sharp eyespot(SE)are serious soil-borne diseases in wheat and its relatives that have been reported to cause wheat yield losses in many areas. In this study, the expression of a cell wall i...Fusarium crown rot(FCR) and sharp eyespot(SE)are serious soil-borne diseases in wheat and its relatives that have been reported to cause wheat yield losses in many areas. In this study, the expression of a cell wall invertase gene, TaCWI-B1,was identified to be associated with FCR resistance through a combination of bulk segregant RNA sequencing and genome resequencing in a recombinant inbred line population. Two biparental populations were developed to further verify TaCWI-B1 association with FCR resistance.Overexpression lines and ethyl methanesulfonate(EMS) mutants revealed TaCWI-B1 positively regulating FCR resistance. Determination of cell wall thickness and components showed that the TaCWI-B1-overexpression lines exhibited considerably increased thickness and pectin and cellulose contents. Furthermore, we found that TaCWI-B1 directly interacted with an alphagalactosidase(TaGAL). EMS mutants showed that TaGAL negatively modulated FCR resistance. The expression of TaGAL is negatively correlated with TaCWI-B1 levels, thus may reduce mannan degradation in the cell wall, consequently leading to thickening of the cell wall. Additionally, TaCWI-B1-overexpression lines and TaGAL mutants showed higher resistance to SE;however, TaCWI-B1 mutants were more susceptible to SE than controls.This study provides insights into a FCR and SE resistance gene to combat soil-borne diseases in common wheat.展开更多
基金supported by the National Natural Science Foundation of China(32270296)the Shenzhen Postdoctoral Scientific Research,China(77000-42100004)+1 种基金the Key Basic Research and Development Program of Hubei Province,China(2020BBA052)the Natural Science Foundation of Guangdong Province,China(2024A1515010498)and the Fundamental Research Funds for the Central Universities,Sun Yat-sen University,China.
文摘Sharp eyespot(Rhizoctonia cerealis)is a widespread soil-borne fungal disease that poses a severe threat to wheat health,and it is one of the main obstacles to achieving stable and high-quality wheat yields in China.Our collaborative team has developed a novel,efficient,and low-toxicity fungicide named Y17991(N-(2-(2,4-bis-(trifluoromethyl)phenoxy)phenyl)-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide).Preliminary laboratory tests confirmed the significant inhibitory effect of this agent on R.cerealis.Large-area field trials also demonstrated its efficacy,with a disease prevention index of 83.52%,which is 1.97%greater than that of the widely used thifluzamide,and it significantly increased the wheat yield.Moreover,this study explored the impacts of Y17991 on the structure and function of the microbial community in wheat rhizosphere soil.Bacterial communities were more strongly affected than fungal communities.Y17991 significantly modulated key amino acid metabolic pathways and certain biosynthetic processes in diseased wheat rhizospheres,and it also enhanced certain biosynthetic pathways and metabolic activities in healthy wheat rhizospheres.Additionally,the application of Y17991 regulated rhizosphere metabolites,thus exerting significant control over the microbial community.We identified 15 microbial strains potentially involved in the prevention and treatment of R.cerealis,and Y17991 treatment promoted the growth of Pedobacter and Bacillus strains.These strains not only aid in plant growth but they also have the potential for disease prevention.In summary,Y17991 application at a reasonable dose does not cause significant disruption to nontarget rhizosphere microbial communities.In future studies,we will continue to investigate the impacts of Y17991 on nonmicrobial components in soil ecosystems,such as protozoa and nematodes.Our research provides a theoretical basis for the scientific application and promotion of new fungicides and offers a significant reference for establishing a comprehensive system for assessing the ecological impact of pesticides on the environment.
基金funded by the National Key Project for Research on Transgenic Biology,China(2016ZX08002001 to Zengyan Zhang)。
文摘The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.
基金funded by the National Key Research and Development Program (2019YFE0118300)the National Natural Science Foundation (31861143008)Henan Major Science and Technology Projects (181100110200) of China。
文摘Fusarium crown rot(FCR) and sharp eyespot(SE)are serious soil-borne diseases in wheat and its relatives that have been reported to cause wheat yield losses in many areas. In this study, the expression of a cell wall invertase gene, TaCWI-B1,was identified to be associated with FCR resistance through a combination of bulk segregant RNA sequencing and genome resequencing in a recombinant inbred line population. Two biparental populations were developed to further verify TaCWI-B1 association with FCR resistance.Overexpression lines and ethyl methanesulfonate(EMS) mutants revealed TaCWI-B1 positively regulating FCR resistance. Determination of cell wall thickness and components showed that the TaCWI-B1-overexpression lines exhibited considerably increased thickness and pectin and cellulose contents. Furthermore, we found that TaCWI-B1 directly interacted with an alphagalactosidase(TaGAL). EMS mutants showed that TaGAL negatively modulated FCR resistance. The expression of TaGAL is negatively correlated with TaCWI-B1 levels, thus may reduce mannan degradation in the cell wall, consequently leading to thickening of the cell wall. Additionally, TaCWI-B1-overexpression lines and TaGAL mutants showed higher resistance to SE;however, TaCWI-B1 mutants were more susceptible to SE than controls.This study provides insights into a FCR and SE resistance gene to combat soil-borne diseases in common wheat.
