不同年份水稻产量性状的QTL分析

Dissection of QTLs in Two Years for Yield Component Traits in Rice (Oryza sativa)

分别于2005年和2006年利用热研2号(粳稻)和密阳23(籼稻)为亲本构建的含111个家系的F6和F7重组自交系群体,对单株穗数、每穗颖花数、每穗实粒数、结实率、千粒重和单株产量6个性状进行了QTL分析。两年共检测到分布于7条染色体上的19个QTL,其中2005年检测到10个,2006年检测到14个,两年相同的QTL5个。大多数性状之间具有显著的表型相关性,相关性较强的性状之间具有较多共同或紧密连锁的QTL。检测到3个控制产量性状的QTL区域存在一因多效或紧密连锁,其中第8染色体上RM5556-RM331区域两年同时检测到控制每穗颖花数、每穗实粒数以及单株产量的QTL。这些QTL为通过分子标记辅助选择提高水稻产量提供了有用信息。

QTLs for six traits including number of spikelets per panicle, number of filled grains per panicle, seed setting rate, number of panicles per plant, 1000-grain weight and grain yield per plant were identified in 2005 and 2006 using a set of 111 recombinant inbred line （RIL） population derived from Nikken 2 and Milyang 23 through consecutive selfing for six or seven generations. A total of 19 QTLs distributed on seven chromosomes were detected, including 10 QTLs in 2005 and 14 QTLs in 2006, and five QTI.s in both 2005 and 2006. Some QTLs controlling different traits shared the same marker interval on the chromosome with each other, which was consistent with their significant phenotypic correlations. Three pleiotropic or tightly linked QTL regions controlling yield and its component traits were identified. The QTLs on chromosome 8 （between markers RM5556 and RM331） were found to be the co-localized regions for number of spikelets per panicle, number of filled grains per panicle and grain yield per plant in the two years. These QTLs provide useful information for high-yield rice breeding through marker-assisted selection.