利用日本晴/9311重组自交系群体定位水稻成熟期叶形相关性状 QTL

摘要

As the main photosynthetic organs,rice leaf morphological characteristic is an important target in high yield breeding.A recombinant inbred line (RIL)population derived from a cross between Nipponbare and 93 1 1 was used to map QTLs for leaf length,leaf width,leaf area and leaf length to width ratio of top three leaves in maturity stage. Correlation analysis showed that there were significant correlation among leaf shape indexes.The leaf shape traits followed a normal distribution with some transgressive individuals,indicating that these complex quantitative traits were controlled by multiple genes.A total of 42 QTLs were detected for these traits,which were mapped on all 12 chromosomes with the phenotypic variations ranging from 4.3% to 29.0%, and the increasing effective alleles contributed by 93 1 1 showed higher additive effect than that from Nipponbare.Seventeen pairs of QTL with epistatic effect were identified among eight traits with explained variations from 3.3% to 23.4%.Pyramiding the positive alleles apparently altered the characters of flag leaf.%水稻叶片是植株进行光合作用的主要器官，优化其形态指标是水稻高产育种的重要目标之一.以日本晴和9311衍生的重组自交系群体(RIL)为材料，对其上3叶的叶长、叶宽、叶面积及叶片长宽比进行考查及 QTL 定位分析.结果表明，各性状在双亲间存在显著或极显著差异，在群体中呈连续分布，表现为多基因控制的数量性状特征；相关分析表明，不同叶位的叶片叶形性状间呈极显著的正相关性；共检测到上3叶的叶长、叶宽、叶面积及叶片长宽比相关 QTL 42个，它们分布于水稻12条染色体上，贡献率介于4．3％~29．0％，来自9311的增效等位基因的数目和加性效应比来自日本晴的要大；另外还检测到17对上位性位点，其贡献率为3．3％~23．4％；还对剑叶叶长、叶宽和叶面积的增效等位基因进行了聚合比较，增效等位基因的聚合能明显调节水稻剑叶的叶长、叶宽和叶面积大小，对其在常规稻和杂交稻的育种应用前景进行了探讨.