Studies Of Fusarium Spp. Pathogenicity Differentiation And Analysis Of Fusarium Graminearum Genetic Diversity In Sichuan

By Fusarium graminearum clade caused by the Fusarium head blight is wheat, barley and cereal crops on very important one of the disease. The occurrence of the scab severity mainly by the pathogen, resistance and varieties of wheat earing flowering of rain wet conditions lift three main factors which influence. In order to understand the scab severity in sichuan province caused the pathogenicity of pathogenic bacteria corrosion spike differentiation and its genetic diversity, the heavy pollution forecast, and provide a basis for prevention and cure disease resistance breeding, we from2008to2011collected from14areas in sichuan province of Fusarium graminearum wheat the irulence measurement and analysis of genetic diversity, and the results are as follows:With three different wheat varieties resistant strains were pathogenic differentiation show that the selected six species of bacteria can make sickle wheat feeling sick, each with the same strains between strains in different varieties has significantly exist between the pathogenicity differentiation; The80strains of Fusarium spp., most of the strong pathogenic strain belong to type, accounting for73.34%, among them the pathogenic types weak, less, were10.83%.15.83%, wheat Fusarium graminearum between virulent strains of the differences.Through the establishment of cereal sickle bacteria ISSR reaction system and sickle bacteria analysis of genetic diversity, with cereal sickle bacteria genomic DNA as a template, orthogonal optimization method to polymerase chain reaction (PCR) system Taq enzyme. primer, dNTP, Mg2+concentration, and other important parameters for four factors4level optimization design (L16(44)), established the suitable for cereal sickle bacterium ISSR-PCR system,25μL PCR system in the optimum reaction conditions for:Mg2+2.5mmol/L, dNTP Mix0.1mmol/L, Taq enzyme1.5U, primer1.2μmol/L, of which10by Buffer3μL, DNA template20ng. Using this optimization system from Columbia University in Canada design of10general primers were studied in article3sequence repeatability and highly specific, strip clear primer for PCR amplification, extended out of33spectral bands,Strip molecular weight in100-1500bp, on average every primer extended out article9with all roads, of which is the digital article26polymorphism bands, polymorphism strip is78.8%, show that sichuan province cereal sickle bacteria has a wealth of genetic diversity, the genetic distance between0.0581-0.638; Clustering analysis results show that in the similarity coefficient0.55place, can be selected strain divided into two groups, the first Ⅰ group has56strains, accounting for59.57%of all strains, similarity coefficient about the0.633place, again is divided into2and group. The Ⅱ group have38strains, accounting for40.43%of all strains, similarity coefficient about the0.687place, again is divided into2and group. Through the above analysis, the results showed that sichuan province cereal sickle bacteria genetic diversity is richer.