水、旱条件下水稻茎秆主要抗倒伏性状的QTL分析

QTL Analysis for Lodging Resistance in Rice Using a DH Population Under Lowland and Upland Ecosystems

以粳型旱稻IRAT10 9和粳型水稻越富杂交的 116个DH株系的群体为材料 ,利用已构建的分子标记连锁图 (包括 94个RFLP标记和 71个SSR标记 ) ,定位了水稻茎秆主要抗倒伏性状的QTL。在水田、旱田栽培条件下 ,考查了乳熟期DH系及其亲本的茎基粗、茎秆长及茎秆强度等性状。相关分析表明 ,茎基粗与茎秆长、茎基粗与茎秆强度及茎秆长与茎秆强度间均呈极显著正相关。利用QTLMAPPER进行水、旱田单环境定位分析及水、旱田联合定位分析定位了控制这些性状的QTL。水、旱田单环境定位分析结果表明 :3个性状共检测到 9个加性QTL和5对上位性QTL ;联合定位分析表明 :茎基粗、茎秆长共检测到 6个加性QTL和 6对上位性QTL ,其中 6个加性QTL和 1对上位性QTL在两种方法下都检测到。旱田条件下检测到 2个加性及 2对上位性QTL(bct1a、cl9、cl6a cl6c和cs5 cs12 )对表型变异的贡献率 (简称贡献率 )大于 30 %。这些高贡献率QTL可能对旱田条件下旱稻抗倒伏分子育种有重要意义。

A DH (doubled haploid) population derived from a cross between Japonica upland rice IRAT109 and Japonica paddy rice Yuefu,was used in this study.Three culm traits,basal culm thickness(BCT),culm length (CL) and culm strength (CS),of DH lines and their parents under upland and lowland ecosystems at milk stage were studied.There were very significant positive correlations between BCT and CL,between BCT and CS and between CL and CS.Data from upland and lowland ecosystems were analyzed respectively and jointly,based on a constructed molecular linkage map(including 94 RFLP markers and 71 SSR markers and covering (1 535.1cM))and the software QTLmapper version 1.0.A total of nine additive QTLs and five pairs of epistatic QTLs associated with BCT,CL,and CS were found by data analysis respectively.Six additive QTLs and six pairs of epistatic QTLs associated with BCT and CL were detected by data analysis jointly.Six additive QTLs and one pair of epistatic QTLs were detected by both methods.Two additive QTLs and two pairs of epistatic QTLs (bct1a,cl9,cl6a-cl6c and cs5-cs12) for culm traits with general contributions of over 30% to phenotypic variation might be useful for upland rice lodging resistance molecular breeding under upland ecosystem.