玉米自交系齐319对玉米灰斑病的抗性遗传分析

利用齐319与10个不同抗病水平的玉米自交系组配的F_1及其与感病自交系丹340、龙抗11构建的F_2群体为试材,通过人工接种鉴定,研究自交系齐319对灰斑病的抗性遗传规律。结果表明,选用齐319作抗性亲本,由其组配杂交组合可明显降低灰斑病发病程度,除与高感材料组配外,均能使杂交组合抗病性达到中抗以上水平。利用单个分离世代分析,齐319与龙抗11组配的后代群体符合B-2模型,即两对加性-显性主基因遗传模型;与丹340组配后代群体符合B-1模型,即两对加性-显性-上位性主基因遗传模型。利用齐319组配群体,在不同遗传背景下,齐319均表现出2对主效抗性基因,在龙抗11背景下表现出的主基因遗传率更高,基因作用方式更简单。

Genetic Analysis of Resistance to Maize Gray Leaf Spot in Inbred Line Qi319

Qi319 and the level of resistance to the GLS of 10 maize inbred lines were used to produce F1, and a highly resistance inbred lines Qi319 and susceptible inbred lines Dan340, Longkang11 were used to produce segregating population for inheritance of resistance to gray leaf spot by using artificial inoculation identification method. The results showed that the incidence of gray leaf spot of the hybrid would be significantly reduced when the Qi319 as a resistant parent in addition to cross with highly susceptible inbred lines, the level of resistance to the GLS was increased to the middle level. Segregation analysis of single separate generation was adopted to study the genetic laws of GLS. The result showed that parents Qi319 and Longkang11 were in accordance with the B-2 model, namely two pairs of major genes with additive-dominant effects. The parents Qi319 and Longkang11 were in accordance with the B-1 model, namely two pairs of major genes with additive-dominant-epistatic effects. Qi319 was used to produce population, it could show two pairs of major resistance genes in different genetic background, but Qi319 could show a higher genetic rate of the main gene in the background of the parent Longkang11.