玉米矮花叶病的抗性遗传分析

Disease Resistance Heredity Analysis of Maize Sugarcane Mosaic Virus(SCMV)by Using Recombinant Inbred Lines(RILs)

以玉米自交系X178和B73杂交培育的183个重组自交系为试验材料，采用人工接种的方法，在苗期、拔节期、抽雄期和成株期进行了玉米矮花叶病的抗性鉴定。结果表明，183份重组自交系之间对玉米矮花叶病的抗性存在着较大的差异，在抽雄期和成株期各有3个高抗的超亲分离；苗期和拔节期的病株率均呈现正态分布，抽雄期和成株期则表现为感病家系较多的偏态分布，且家系病株率的变异系数随生长发育变得越来越小，但抗性遗传力则越来越大。说明对玉米矮花叶病的抗性鉴定在成株期较准，苗期受环境影响较大；成株期的抗性由2—3对主基因控制，同时存在多基因修饰或互作；抗性基因之间以加性效应为主。

In this research, a recombinant inbred lines（RILs）population including 183 lines derived from a cross of X178 and B73 through the single seed descent method was used to analyze the genetic conferring resistance to maize SCMV. The results showed：certain resistance variations appeared between family lines, part of these family lines possess better disease resistance character than their parents lines, therefore this population is an ideal germplasm resource of disease resistance breeding to maize SCMV. Population average susceptible rate close to parents lines level, family lines distribution reached normal distribution during seedling stage and elongation period, this means scmv resistance appears to be genetics of quantitative characters;family lines reached skew distribution during anthesis and grain-filling, and susceptible plants increased, through analysis, we considered there are 2 - 3 major scmv resistance genes in X178 germplasm during later growth stage, and these genes expressed disease resistant character mainly through additive effect of favorable genes.