籼稻落粒性QTL定位与环境互作效应检测

利用珍汕97B／密阳46所构建的RIL群体(ZM-RIL)及其相应分子遗传图谱,在海南和杭州两地试验,以稻穗下落法测得落粒率(％)为指标,进行两地数据QTL联合分析。结果表明,ZM-RIL群体的不同株系在两地间落粒率变化很大。在海南,该性状呈近似正态分布;在杭州,则呈明显偏态分布。试验共检测到7个主效应QTL,位于第1、2、3(2个)、6、7和11等6条染色体上,每个QTL影响落粒率的加性效应均不大,其幅度为1．7％～3．9％,共解释群体落粒性性状变异的8．53％。其中,有3个主效应QTL(qSH3-1、qSH3-2和qSH6)存在显著的GE互作,它们均使海南增加落粒率和杭州降低落粒率,且GE总贡献率几乎接近加性效应总贡献率,表明GE互作对落粒率具有重要影响。此外,试验还检测到5对上位性互作QTL,这些互作共解释群体落粒性性状变异的3．39％,单个互作的贡献率为0．47％-0．85％,未检测到上位性与环境的显著互作。

Mapping QTLs for Rice Shattering Trait and Analysis Major Effects

The recombinant inbred line populations derived from Zhenshan 97B/Miyang 46 and its genetic linkage map were used to map the QTLs controlling the shattering trait in two environments, Hainan and Hangzhou. The results indicated that the shattering of different lines ZM-RIL population varied dramatically in different environments. In Hainan, this trait nearly showed the normal distribution, while in Hangzhou, it showed distorted distribution. A total of seven QTLs with main effects were detected on the chromosome of 1, 2, 3 (two QTLs), 6, 7 and11. Each QTL only contributed little (from 1.7% to 3.9%) to the total phenotypic variations, even in total they only explained 8.53% of the variations. Of them, three QTLs (qSH3-1, qSH3-2 and qSH6) had significant GE interaction effects, and their effects increased shattering in Hainan and decreased it in Hangzhou. The total contribution of these GE interaction QTLs were as large as those QTLs with main effects, suggesting that GE effects were important for shattering. In addition, five pairs of epistasis QTLs were detected with each contributing to 0.47%~0.85% of the total variation, even in whole, they only explained 3.39% of the total variation. No epistasis by environment interaction effect was detected in this experiement.