水稻穗干物质重发育动态的QTL定位

 以籼稻品种IR64和粳稻品种Azucena及其DH群体(123个DH系)为遗传研究材料,在穗干物质积累的不同时期测定穗重。利用包括RFLP、同工酶标记和RAPD等175个分子标记的水稻连锁图谱,采用条件复合区间作图法对水稻穗部干物质积累进行QTL的动态定位。在各时期能检测到14个非条件QTL,而最终穗重只能检测到3个非条件QTL。条件QTL分析表明,基因在水稻发育过程中以一定的时空方式表达。亲本和极端个体的QTL总效应分析表明,增效基因和减效基因在不同个体中的累积程度不同。控制穗干物质积累的发育过程存在两组基因,一组基因控制稻穗谷粒内外颖的发育,另一组基因可能控制谷粒内容物的充实。

QTL Mapping for Developmental Behavior of Panicle Dry Weight in Rice

A population of 123 double haploid (DH) lines, derived from a cross between an indica variety IR64 and japonica variety Azucena was used in this study. The panicle dry weight at different stages was measured at 10 day intervals. Based on the rice genetic linkage map of 175 molecular markers, including RFLP, enzyme markers and RAPD, QTLs for the developmental behavior of panicle dry weight were determined dynamically using composite interval mapping method in combination with the conditional analysis method. The number of unconditional QTLs for panicle dry weight detected for time dependent measure was 14. However, only 3 QTLs were detected at the final stage. Conditional QTL analysis of rice panicle dry matter accumulation could provide an insight into both spatial and temporal patterns of gene expression. By comparing the sum of QTL additive effects for parents with that for extreme ideal individuals, we found that the alleles of positive or negative gene effects were dispersed in various individuals. The result also indicates that two sets of genes might be involved in the process of panicle dry matter accumulation. The development of the husk of rice kernel, lemma and palea is determined by one set of genes, while that of the rice kernel content is controlled by the other set of genes.