水稻剑叶角度与主穗产量的遗传剖析

Genetic Dissection of Flag Leave Angle and Main Panicle Yield Trais in Rice

理想水稻株型的选育与高产育种密切相关,而剑叶角度则是构成水稻理想株型的重要指标之一,同时也是影响水稻产量的重要因素。合理开发利用水稻中控制剑叶角度及产量相关的数量性状基因座位(QTL),并结合分子育种技术,可更好地为高产制繁种目标服务。通过应用由244个株系组成的珍汕97B/密阳46重组自交系(RIL)群体,构建含256个分子标记的连锁图谱,采用QTL区间作图法对剑叶角度及主穗产量等5个性状进行定位分析,共检测到17个QTL,分布于染色体1、2、3、5、6、9、10、11。这些QTL对相应性状的贡献率介于3.46%～25.64%之间。在第1染色体上检测到控制5个性状的QTL,其中控制剑叶角度的两个QTL;在第2、3、9、10、11染色体上分别检测到各一个QTL;第5染色体上检测到控制剑叶、每穗总粒数和每穗实粒数的3个QTL;1个每穗实粒数和2个每穗实粒重的QTL分布于第6染色体上。多个区间表现出对两个性状的显著作用,其中第1染色体2个,第6染色体1个。相关性分析表明,较小的剑叶角度可通过提高结实率进而显著增加产量。

High rice yield was contributed by ideal rice architecture greatly, and flag leave angle was one of the most important components of the ideal rice architecture, which effects rice yield gaining. With the advance of Marker Assisted Selection （MAS）, finding and using quantitative trait loci （QTL） conditioning flag leave angle and other yield traits would contribute to high yield gaining drastically. A linkage map consisting of 256 DNA markers were constructed by using a recombinant inbred line （RIL） population derived from the indica-indica rice cross Zhenshan 97BxMilyang 46. QTL conditioning flag leave angle （FLA） and other four grain yield traits were determined at the one-locus level. Seventeen QTL were detected to have significant additive effects for these traits. General contributions to the phenotypic variance were between 3.46% - 25.64%. QTL conditioning the all five traits were detected on chromosome 1,of which two were for FLA; each QTL were detected on chromosome 2,3,9,10and ll,respectively; three QTL for FLA,total number of spikelets per panicle （TNSP） and number of filled grain per panicle （NFGP） respectively were detected on chromosome 5; one QTL for NFGP and two QTL for grain weight per panicle （GWP） were detected on chromosome 6.Correlation analysis revealed that flag leave angle increased grain yield by increasing spikelet fertility.