The Progeny Of Wheat-psathyrostachys Huashanica Keng Cytogenetics Research And Evaluation Of Wheat Germplasms Resistant To Sharp Eyespot(Rizoctonia Cerealis)

Wheat sharp eyespot,one of the most important diseases,has affected worldwide wheat yeild and quality,In recent years,its occurrence area and damage degree in Chinese major wheat-growing areas have been increasing obviously.Because of the scarcity of resistant sources in wheat,it is necessary to explore new resistant resource in the related species of wheat.Psathyrostachys huashanica Keng(NsNs,2n=14),possessing many excellent biological characteristics,such as great stress tolerance,prematurity and disease resistance,is an important wild relative of wheat.In this study,cytological observation,genomic in situ hybridization(GISH)and molecular markers(SSR,EST-STS)were used to identify 59wheat-P.huashanica derived lines which created by our group resently to clarify their chromosome constitutions.Greenhouse toothpick inoculation,combined with agronomic characters investigation,was used to screen great resistant materials to wheat sharp eyespot from above 59 wheat-P.huashanica derived lines and 97 adopted American materials and domestic improved varieties.Then molecular markers(SSR and SNP)were used to analyse the stable resistant materials.The main results of the experiment were as follows,1.The results of cytogenetic identification showed that 18-1-3-1-6-2-2 was 2Ns(2D)substitution line.The root tip cells of remaining materials consisted of 42 chromosome without obvious exogenous signals,thus the remaining materials conjectured to be introduced small fragments of chromosome derived from Ns genome,and be translocation lines or introgression lines.2.The results of the indentification of wheat resistance to sharp eyespot showed that 36 materials with stable moderate-resistance were obtained,including 10 domestic improved varieties,16 adopted American materials and 10 progenies of wheat-P.huashanica derived lines.The results of agronomic traits of 36 resistant materials showed that Y-83-1 and Y-83-3had good agronomic traits and resistance,can be used as stable resistant materials for wheat breeding.3.504 allele variations were detected in 36 resistant materials using SSR markers,and the allele number per locus was 8.40,ranged from 2 to 23.The genetic diversity analysis showed that adopted American materials had higher genetic diversity,and its relationship to wheat-P.huashanica derived lines was distant.Resistant loci analysis indicated that Xbarc126 and Xwmc154 can be used for molecular marker assisted breeding.The genetic constitution of Y-83-1 and Y-83-3 were analyzed using SNP markes.The identification of the resistance of wheat-P.huashanica derived lines to sharp eyespot can lay a material and theoretical foundation for germplasm innovation and breed improvement against wheat sharp eyespot.