Zhang Yu-Shan, Wu Wei, Xu Cai-Guo
Univesity of Electronic Science and Technology of China Zhongshan Institute, Zhongshan 528402, China.
Yi Chuan. 2008 Jun;30(6):781-7. doi: 10.3724/sp.j.1005.2008.00781.
Spikeletes per panicle (SPP) is one of the important yield components in rice (Oryza sativa L.). Appropriate heading date (HD) and plant height (PH) are prerequisites for desired yield. In this study, the near isogenic lines (NILs) of chromosome 7, which harbored QTLs controlling HD, PH and SPP were constructed based on the primary QTLs results of the recombinant inbred lines (RILs) derived from Zhenshan 97 and HR5. The near isogenic lines (RILs) of chromosome 8, which harbored QTLs of HD, PH, and SPP, were constructed using heterogeneous inbred family based on RILs. The genetic effects of two pleiotropic intervals were assessed accurately in these two NILs. The QTLs identified by the two near isogenic lines indicated that the three traits were controlled by the same QTL or tightly linked QTL. The QTLs controlling the three traits had the same direction on additive effects and dominant effects. And these traits showed bimodal or discontinuous distributions in respective NILs. These results imply that the same gene might control the three traits simultaneously (i.e., the gene pleiotropism). Along with this, the relationships between HD and PH and yield, the application of significantly positive correlation for the three traits in breeding program, and the advantage and disadvantage of the two constructing NILs methods were also discussed in this study.
每穗小穗数（SPP）是水稻（Oryza sativa L.）重要的产量构成要素之一。适宜的抽穗期（HD）和株高（PH）是获得理想产量的前提条件。本研究基于珍汕97和HR5衍生的重组自交系（RILs）的初步QTL定位结果，构建了携带控制抽穗期、株高和每穗小穗数QTL的第7染色体近等基因系（NILs）。利用基于RILs的异质自交系构建了携带抽穗期、株高和每穗小穗数QTL的第8染色体近等基因系（RILs）。在这两个NILs中准确评估了两个多效区间的遗传效应。两个近等基因系鉴定出的QTL表明，这三个性状受同一个QTL或紧密连锁的QTL控制。控制这三个性状的QTL在加性效应和显性效应上具有相同的方向。并且这些性状在各自的NILs中呈现双峰或不连续分布。这些结果表明同一个基因可能同时控制这三个性状（即基因多效性）。与此同时，本研究还讨论了抽穗期与株高以及产量之间的关系、这三个性状在育种计划中的显著正相关应用，以及两种构建NILs方法的优缺点。
