大麦主栽品种亲缘系数和对叶斑病的抗性分析

为明确我国大麦主栽品种的遗传多样性及其对叶斑病的抗性来源,采用亲缘系数(COP,coefficient of parentage)分析方法对155个主栽大麦品种的遗传系谱进行聚类分析,同时对其中79个供试大麦品种在苗期和成株期分别接种2个强毒性菌株进行抗性鉴定。结果显示,155个品种聚为6个类群,有亲缘关系的品种占全部品种14.77%。在品种间组成的11935个组合中,1763个组合间存在亲缘关系,其COP值变化范围在0~0.7500之间,亲缘系数总和为157.5867,平均值为0.0132。根据系谱分析发现了不同育种单位所育品种的核心亲本,并追溯其主要的祖先亲本。此外,通过对叶斑病的抗性鉴定,发现大多数供试的大麦品种感叶斑病,高抗品种主要集中在垦啤麦系列品种和蒙啤麦3号,部分华大麦和驻大麦系列的品种在苗期或成株期中抗叶斑病。系谱分析及抗性鉴定结果揭示了我国大麦叶斑病抗性基因存在不同来源,分析结果有利于提高抗叶斑病基因筛选效率和缩小筛选范围,也将促进抗叶斑病新基因资源的发掘和利用。

Analysis on Coefficient of Parentage of Major Barley Varieties and Their Spot Blotch Resistance

In order to elaborate the genetic diversity of the major barley varieties planted in China and their resistance origins to spot blotch caused by Cochliobolus sativus, the coefficient of parentage (COP) was utilized to cluster 155 major barley cultivars with their pedigree information, meanwhile 79 varieties of them were inoculated with 2 strains of high virulence at both seedling and adult-plant stages. Based on the results, the 155 major barley varieties were clustered into 6 families, and 14.77 % of them possess genetic relationships with each other. There are 1763 variety combinations found with genetic relationships among the total 11935 ones, and the COP values range from 0.0000 to 0.7500, its average COP value is 0.0132. According to the pedigree analysis, the core parents for those varieties developed by different breeding institutes were identified and their possible primary parents were also deduced. In addition, most of the tested cultivars were susceptible to spot blotch in seedling and adult-plant stages. Among them, several varieties in the series of Kenpimai ones and Mengpimai No.3were identified to be highly resistant to spot blotch, and a few varieties of series of Huadamai and Zhudamai showed moderate seedling or adult-plant resistance. The results of pedigree analysis and resistance characterization of spot blotch revealed that the resistant genes utilized in the barley varieties in China may derive from different genetic backgrounds. The analyses will promote the efficiency of resistant genes selection, minimize barley accessions to be screened and accelerate the progress of exploitation and utilization of new spot blot resistance genes germplasm.