利用DH群体定位水稻谷粒外观性状的QTL

Quantitative Trait Loci for Grain Appearance Traits of Rice Using a Doubled Haploid Population

采用混合线性模型的复合区间作图方法,对水稻“圭630”和“02428”组合的DH群体的谷粒外观性状——粒长、粒宽和粒形进行了数量性状基因定位,同时对定位的主效应和上位性进行了环境效应分析。2002年对粒长、粒宽和粒形分别检测到5、4和2个QTLs;2003年对以上3个性状分别检测到3、4和4个QTLs。其中4个QTLs在2年均检测到,且其贡献率较大。位于第4染色体C22-RG449d区间的QTL效应大,同时影响粒长和粒宽,2年内均被检测到。联合2年数据分析分别检测到6个粒长QTLs、6个粒宽QTLs和3个粒形QTLs,共解释各自性状变异的67.71%、50.08%和29.17%,且影响粒形的3个QTLs同时影响粒长或粒宽。对粒形和粒宽分别检测到4个QTLs与环境之间存在显著互作。本实验中检测到主效应和上位性对谷粒外观性状均具有重要作用,但上位性贡献率相对主效应较小,环境互作效应更小。

Rice grain shape is an important agronomic characteristic. Genetic and genotype ×environment interaction effects were studied for apparent quality tra its of a DH population from the cross between Gui 630 and 02428. Based on mixed linear model QTL mapper 1.0, quantatitative trait loci (QTL) mapping was carried out for grain appearance traits such as grain length, grain width and grain sha pe in rice in 2002 and 2003 years, five, four and two QTLs were detected for gra in length, grain width and grain shape, respectively, in 2002; In 2003, three, f our and four QTLs were identified for the three traits, respectively. Of them, f our QTLs were simultaneously identified in both of the years, and with great con tributions. The QTL with the largest effects located in the interval C22-RG449d on chromosome 4 not only affected the grain length but also control grain width, and which was detected in both years. Combined two years data analyzed the gene tic and genotype×environment interaction effects, six, six and three QTLs were identified for the grain length, grain width and grain shape, respectively. Thei r general contributions were 67.71%, 50.08% and 29.17%, respectively. At the sam e time, the three QTLs affecting grain shape shared similar regions with grain l ength or grain width. Respectively four QTLs for grain length and grain width we re found to be significant interaction with environment, but no QTL for grain sh ape. Meanwhile, main effects and epistatic QTLs were investigated to have an imp ortant effect on grain appearance traits, but the general contribution of epista tic effects less than maineffects, and contribution of environment interaction l ess than epistatic effects.