小麦赤霉病抗性QTL分析

Analysis of QTL for Fusarium Head Blight Resistance in Wheat

以小麦赤霉病抗源望水白与感病品种Alondra杂交产生的 10 4个重组自交系为材料 ,采用JoinMap○R3 0软件构建了含有 2个RAPD、10 9个SSR和 10 5个AFLP标记共 2 5个连锁群的遗传连锁图 ,其中 2 4个连锁群可以确定为相应的染色体 ;采用自然发病和土表接种方法 ,对该重组自交系群体在建阳和苏州进行了连续两年赤霉病抗性鉴定 ,结果表明 :小麦赤霉病抗性由多基因控制 ,存在主基因效应 ,抗病基因表达受环境条件影响较大。用MapQTL○R4 0软件进行了赤霉病抗性QTL分析 ,共检测到位于染色体 2A、3B、4A、4D、5A、5B、6A、6B和 7A的 10个QTL ,其中 8个由抗病亲本望水白提供 ,2个由感病亲本Alondra提供 ,分别可以解释 8 3%～ 2 3 6 %的赤霉病抗性。与赤霉病抗性QTL紧密连锁的两侧分子标记可以为小麦抗赤霉病分子辅助育种提供帮助。

With the population of 104 F 7-derived recombinant inbred (RI) lines from Wangshuibai (resistance to Fusa- rium head blight) and Alondra (Susceptible) as mapping population,the wheat genetic map consisting of 2 RAPDs,109 SSRs and 105 AFLPs markers was constructed by JoinMap ○R 3.0 software. Up to 24 of the 25 identified linkage groups were identified to the chromosome. The FHB resistance of RI lines was evaluated by natural infection and soil surface inoculation in Jianyang and Suzhou for two years. The results showed that resistance to FHB was inherited in a quantitative manner and controlled by few genes with major effects,but the expression of these resistance genes were strongly affected by environment. 10 QTLs,8 derived from Wangshuibai and 2 from Alondra,associated with FHB resistance were detected using MapQTL ○R 4.0 software. They were located on the chromosomes 2A,3B,4A,4D,5A,5B,6A,6B,7A and explained 8.3%-23.6% of the phenotypic variance for FHB resistance respectively. It is suggested that the flanking markers of QTL may be used in the breeding for resistance to FHB by marker-assisted selection.