Establishment And Application Of Wheat Fusarium Head Blight System With Brachypodium Distachyon

Wheat Fusarium head blight is a worldwide fungal disease caused by many kinds of Fusarium spp.,which seriously affects the quality and yield of wheat.The wheat genome is larger,and the repeat sequence is more,it is difficult to study.Brachypodium as a new mode of Gramineae plants,the growth condition is simple,high efficiency of genetic transformation,has great advantages in the study of gene function.This study firstly Brachypodium and wheat and Gibberella interaction were studied,established system of using Brachypodium to study Wheat Scab.The application of the system in scientific research is expounded from two aspects of the research of the gene function of the resistance pathway and the selection of the 49 wild short stalk grass planting resources.The main findings are as follows:1.Through the experiment of the inoculation of the ear of the short stalk,the leaves and the germ the interactions between Fusarium and short stalk were determined,At a temperature of 28 ℃ relative humidity of 75% will exhibit similar symptoms of wheat scab Brachypodium Ear Fusarium after inoculation,established system of using Brachypodium to study Wheat Scab.2.38 genes on the pathway of disease resistance were cloned from wheat,and all of the genes were mediated by Agrobacterium mediated transformation,and a total of 35 genes were obtained from the transgenic plants,the transformation efficiency ranged from 0-46.25%.3.There are 21 genes have been homozygous transgenic lines,21 of these transgenic lines T2 and T3 generations generations were inoculated experiments Spike.Found that transfer Ta WRKY2 and Ta WRKY40 two genes plants and the control compared showed strong resistance to scab,Leaf Culture in vitro discovery leaves showed consistent Spike inoculation phenotype.Description Ta WRKY2 and Ta WRKY40 can indeed enhance Brachypodium disease resistance.4.The experiments were inoculated immature wheat embryos 2902 was used to transform two candidate genes,the callus induction rate of wheat immature embryos was 86.5%,which was 2511;Ta WRKY2 and Ta WRKY40 for genetic transformation of callus were 780 and 1731,Callus differentiation rate was 32.6% and 48.3%,respectively;after high concentrations screening agents screened resistant plants were 54 and 128,resistance seedling rate was 21.3% and 11.3%,respectively;After Basta smear resistant plants leaves and PCR testing only got Ta WRKY40 gene of a transgenic plant,conversion efficiency of 0.58%.5.49 wild germplasm materials were selected,and the germplasm materials of 3 natural conditions were obtained,which were PI317418,PI254868,W639284,respectively.Genetic transformation of these 3 materials,after GUS histochemical staining of the 3 short stalk grass species can be carried out genetic transformation.Conversion rates were 24.44%,19.6%,6.38%,respectively.