籼稻不同定位群体的抽穗期和株高QTL比较研究

 【目的】通过分析控制不同定位群体水稻抽穗期、株高和产量性状表现的QTL，挖掘同时控制株高与产量性状且对抽穗期影响小的QTL区间，为水稻高产育种提供参考。【方法】以杂交稻恢复系密阳46作为共同父本，分别与保持系协青早B和珍汕97B配组，构建2个籼籼交重组自交系群体，在同一地点多年种植，对不同群体抽穗期和株高相关的QTL定位结果进行比较。【结果】共定位到12个抽穗期QTL和11个株高QTL，其中2个抽穗期QTL在2个群体中都能检测到，分别位于第6染色体短臂和第7染色体长臂近着丝粒区域。通过与前期相同群体产量性状QTL定位结果比较，发现6个多效性区间，其中，1个同时控制抽穗期、株高和产量性状，3个同时控制抽穗期和产量性状，2个同时控制株高和产量性状。【结论】相对于共同的父本密阳46，水稻矮败型保持系协青早B与野败型保持系珍汕97B对抽穗期和株高的遗传控制存在较大差异，并以株高更为明显。第2染色体长臂RM6—RM240的QTL作用较稳定，对株高和产量性状作用方向一致，且对抽穗期无显著影响，对于通过“矮中求高”实现水稻高产育种具有重要的应用价值。

Mapping of Quantitative Trait Loci for Heading Date and Plant Height in Two Populations of Indica Rice

【Objective】 Analysis of quantitative trait loci (QTLs) for heading date, plant height and yield traits and identification of QTLs having pleiotropism on plant height and yield traits but insignificant effect on heading date would facilitate the rice improvement for high-yielding potential. 【Method】 Two recombinant inbred line populations of indica rice were constructed using restorer line Milyang 46 as the common male parent and maintainer lines Xieqingzao B and Zhenshan 97B as the female parents, respectively. The two populations were planted in a trial site in multiple years for the detection of QTLs for heading date and plant height. 【Result】 A total of 12 QTLs for heading date and 11 QTLs for plant height were detected, among which only two QTLs for heading date locating on the short arm of chromosome 6 and the pericentromeric region of chromosome 7 were found in both populations. In comparison with QTLs for yield traits previously detected in the two populations, six QTL regions showing pleiotropic effects were found. Included are one controlling heading date, plant height and yield traits, three controlling heading date and yield traits, and two controlling plant height and yield traits. 【Conclusion】 In related to the common parent Milyang 46, the maintainer lines Xieqingzao B for dwarf-abortive cytoplasmic male sterility and Zhenshan 97B for wild-abortive cytoplasmic male sterility differ greatly in the genetic control of heading date and plant height, especially in plant height. QTL qPH2 in the interval RM6-RM240 on the long arm of chromosome 2 is of great potential in practicing the “higher in dwarf” approach to increase rice yield, since it showed a consistent effect on plant height and yield traits with insignificant effect on heading date.