利用RIL群体对水稻再生力及相关农艺性状的QTL分析

QTL Analysis of Rice Ratooning Ability and Related Agronomic Traits by Using RIL Populations

以粳糯稻品种糯89-1与籼型重穗型杂交稻骨干恢复系蜀恢527杂交构建的籼粳交F7代RIL群体的169个家系为作图群体,构建了一张含105个微卫星(SSR)标记的分子连锁图谱。定位了水稻正季7个农艺性状的QTL15个,分布在第1、第2、第3、第5、第6、第7、第10染色体上,LOD值介于2.10～7.51,贡献率3.77%～25.37%,其中贡献率10.0%以上的QTL7个,单个性状的QTL1～4个;定位了水稻再生季7个农艺性状的QTL19个,分布在第1、第2、第3、第4、第5、第6、第7、第10染色体上,LOD值介于2.17～18.34,贡献率3.23%～37.66%,其中贡献率10.0%以上的QTL7个,单个性状的QTL1～5个;定位了影响水稻再生力(最终再生率)的QTL2个(qRA4,qRA5),分别在第4和第5染色体上,贡献率分别为8.17%和7.09%,加性效应分别为0.32和0.39,贡献率和加性效应均较小,属微效基因。共检测到两季农艺性状QTL36个,同一性状被重复检测的QTL8个。水稻再生力与正季稻有效穗呈极显著负相关;水稻再生力与再生稻有效穗呈极显著正相关,与每穗总粒数和着粒密度呈显著负相关。QTL定位结果揭示了有效穗是影响再生力的主要因素。

A molecular linkage map containing 105 SSR marks were constructed by using a RIL population generated from the F7 descent of a cross of japonica glutinous rice variety 89-1 and an indica heavy panicle backbone hybrid rice lines SH527. By using this map, we mapped 15 QTLs for seven agronomic traits in the normal season, which was distributed on chromosomes 1, 2, 3, 5, 6, 7, and 10, respectively. The LOD value varied from 2.10 to 7.51, and the contribution rate varied from 3.77% to 25.37%, among which seven QTLs had the contribution rate larger than 10.0%. The number of a single trait QTL varied from 1 to 5. Two QTLs （qRA4, qRA5） affecting rice ratooning ability were detected on chromosomes 4 and 5, the contribution rate was 8.17% and 7.09%, and the additive effect was 0.32 and -0.39, respectively. Thirty-six QTLs for agronomic traits were detected in two sea- sons and among which eight were detected repeatablely. According to the results, the ratooning ability was remarkably negatively related to the effective ear of the normal season. In addition, the ratooning ability was tightly positively related to the effective ear in the ratooning season, and was negatively related to the grain number per ear and seed density. The QTLs mapping results re- vealed that the effective ear of normal season and ratooning season is the main factor that affects rice＇s ratooning ability.