10份小麦持久抗性资源和6份新品系抗条锈病的遗传特点分析

小麦条锈病是长期威胁我国小麦生产安全的重要气传病害。由于病原菌(Puccinia striiformis f.sp.tritici,Pst)群体毒性结构高度变异,我国小麦条锈病防治工作经常面临严峻挑战。培育和广泛利用抗病品种是防治小麦条锈病最为经济有效的措施。因此,鉴定抗源和探究持久抗病基因型的遗传模式能为抗病育种提供抗病新基因和理论指导,具有重要意义。我国部分持久抗条锈病的小麦品种和新育成抗病品系的抗性遗传特点尚未明确,本研究中以这些抗病品种或品系作父本,高感病品种‘Taichung 29’或‘铭贤169’作为母本进行有性杂交,构建遗传群体,在成株期利用条锈菌优势小种CYR32进行接种鉴定,分析其抗病性遗传组分及遗传特点。在10个持久抗条锈病品种中,多数品种(8个)由1对或2对隐性遗传基因控制;6个新育成抗病品系中,多数(4个)含有单个抗病基因,隐性或显性遗传偏向性不明显。因此,隐性遗传抗病基因在持久抗条锈病品种中发挥更重要的作用。另外,新育成品系‘WJ10-97’对CYR32号小种具有慢条锈性特点,可作为新抗源用于小麦品种选育。

Genetic trait analyses of the stripe rust resistance of ten durable resistant wheat germplasm resources and six new lines

Stripe rust has been one of the most important airborn diseases threatening wheat production security in China for a long history.Due to the high variability of virulence structures among populations of the pathogen Puccinia striiformis f.sp.tritici(Pst),the disease control of wheat stripe rust in China has been severely challenging.It is the most economical and effective control strategy against stripe rust to develop and widely use disease resistance wheat varieties.As a result,it is valuable to provide new resistance genes and theoretical instructions for disease resistance breeding through identification of resistant germplasm resources and genetic model characterization of the durable resistance varieties.The genetic characteristics of several durable resistant wheat varieties and new lines in China are unknown.In this study,these resistant varieties or lines were used as male parents to cross highly susceptible female parents of‘Taichung 29’or‘Mingxian 169’to set up genetic populations.The offspring plants of the crosses were inoculated with the predominant race of Pst CYR32 at the adult-plant stage for phenotype rating,and their resistant components and genetic traits were analyzed.The resistence of most of the ten durable varieties(eight varieties)against stripe rust was dominated by one or two gene(s)inherited recessively,while most of the six lines(four lines)developed recently contained only one resistance gene,and their propensity of genetic dominance of recessiveness was not significant.Consequently,the resistance gene(s)inherited recessively might play more important roles in the durable resistance varieties.In addition,the new line‘WJ10-97’showed slow rusting to Pst race CYR32 and could be used in wheat breeding programs as a resistant parent.