水稻胚芽鞘长度与抗旱性的关系及QTL定位

 对由水稻品种珍汕97B和旱稻品种IRAT109构建的重组自交系195个株系的胚芽鞘长度及抗旱系数的研究表明,水分胁迫下水稻重组自交系群体的胚芽鞘长度与抗旱系数的相关系数为0.2206**。应用由213个SSR标记构建的遗传连锁图对控制胚芽鞘长度和抗旱系数的QTL进行了定位。检测到胚芽鞘长度和抗旱系数的主效QTL各为13个和5个，单个QTL对表型的贡献率为2.28%～22.65%；在第9染色体上两者的QTL出现在相同的分子标记区间（RM160-RM215）。检测到胚芽鞘长度和抗旱系数的互作位点分别为17对和3对，影响胚芽鞘长度的互作位点联合贡献率为5835%；影响抗旱系数的互作位点联合贡献率为11.93%。控制胚芽鞘长度和抗旱系数的QTL分别与其他研究中控制根系性状（深根干质量、根深、根长、根数等）的QTL位于相同的标记区间。

Relationship Between Coleoptile Length and Drought Resistance Index of Rice and Their QTLs

A set of recombinant inbred lines (RILs) population including 195 lines derived from a cross of Zhenshan 97B (lowland rice variety) and IRAT109 (upland rice variety) was used for correlation analysis and QTL identification for coleoptile length (CL) and drought resistance index (DRI). The correlation coefficient between CL and DRI under water stress was 0.2206~ ** . A total of 13 and 5 QTLs for CL and DRI under different conditions were identified, respectively. The phenotypic variance explained by each QTL ranged from 2.28% to 22.65%. qCL9 possessed the same location (RM160-RM215) with qDRI9. Seventeen epistasis loci for CL were detected with 58.35% of total contribution; three pairs of epistasis loci for DRI were detected with 11.93% of total contribution. Comparing the QTLs related to drought resistance in other studies, QTLs of CL and DRI were located in the same or adjacent marker interval with the QTLs related to root traits, for instance, dry weight, root depth, root number and root length.