Study On The Fitness Of The Anti-Carbendazim Of Fusarium Graminearum And An Ananlysis Of The Function Of A Gal4-like Gene

Fusarium head blight caused by Fusarium spp.occurs worldwide on small grain cereals.In China,Fusarium head blight is mainly caused by Fusarium graminearum species complex(FGSC).For the prevention and control of wheat scab,China mainly uses to carbendazim based and imidazole medicament chemical control,due to the long-term continuous use of such agents in the prevention and control of wheat scab,causing pathogenic bacteria develop resistance.Years of resistance monitoring found that carbendazim resistant strains in the population ratio upward trend.Therefore,it is a question that carbendazim can continue to be used in the prevention and control of wheat scab.In order to determine the sultability of carbendazim resistant strains of the wheat scab pathogen,we randomly selected resistant strains and sensitive strains of Wheat Fusarium head blight,which were collected and separated from 2015 and tested by carbendazim sensitive level.Through the identification of the comprehensive species,species identification and chemical identification,we screened out 48 strains of resistant strains and 50 strains of sensitive strains of the 3Ac-DON chemical,and compared the biological characteristics and pathogenicity of the resistant strains and the sensitive strains.The results showed that the growth rate of the sensitive strain group was significantly greater than that of the resistant strain group.In the carrot culture medium,resistant and sernsitive strains are not dominant in perithecigerous capacity.Using solid culture medium for producing the toxic,the application of HPLC detection system were examined in a sample of Don toxin content,it was found that toxin production of sensitive strains group was significantly greater than that of the resistant strain group.In wheat flowering stage,we inoculated wheat head on flowering stage with conidia of 48 strains of resistant strains and 50 strains of sensitive strains,the result showed that the pathogenicity of sensitive strains group was higher than that of resistant strains group,and there were significant differences.Therefore,it is inferred that the fitness of the sensitive strain group is better than that of the resistant strain group.Studying Fusarium graminearum pathogenicity-related genes function,it can lay the foundation for the study of Fusarium graminearum pathogenic molecular mechanisms and provide a theoretical basis for the development of new disease-resistant wheat breeding and target agents.The functional analysis of FGSG 08010.3 gene of Fusarium head blight of Wheat was performed in this study.The gene named as FgGal4-likel encodes a protein that contains a functional domain of the GAL4-like protein,which is a fungal specific transcription factor.In this study,taking the wild type strains of Fusarium graminearum PH-1 as test materials,we employed the method of split marker PCR to construct the knockout vector containing Hygromycin-resistant gene hph.We got the Hygromycin?resistant transformants by PEG-mediated transformation of protoplasts of PH-1 and homologous recombination.We get five the deletion mutant by PCR and RT-PCR.The revertant DNA fragment was constructed and the mutant was obtained by protoplast transformation.Through the screening of the G418 and hygromycin B and PCR verified,we obtained two in situ repair mutants.We observed the phenotype change and pathogenicity of deletion mutant and recovery mutant,and determined their pathogenicity to wheat.The results showed that mycelial morphology,growth rate and colony colour of the knockout transformants had no significant differences compared to wild strain PH-1.The conidia production was slower and much less than the wild strain.The yield of the spores was less than that of the wild type strain.In perithecigerous,there was no significant difiference between wild-type strains and transformants.In the field of pathogenicity,the transformation of the strain was weaker than that of the wild type strain.Therefore,it is speculated that the FgGa14-likel gene may be related to the production of the spores and pathogenicity.