粳稻发芽期耐碱性的QTL检测

 以粳粳交高产106/长白9号的200个F2:3株系为作图群体，在0.15% Na2CO3溶液碱胁迫下，进行了水稻发芽率及其相对碱害率的鉴定评价，并以SSR标记构建的分子连锁图谱为基础，对水稻发芽率及其相对碱害率进行了数量性状基因座(QTL)检测。结果表明，在F3株系群中水稻发芽率及其相对碱害率均呈单峰接近正态的连续分布。共检测到碱胁迫下与水稻发芽率相关的QTL 7个，对表型变异的贡献率范围为4.05%～12.61%，其中位于第6染色体RM225-RM204区间的qGC 6和位于第9染色体RM219-RM3700区间的qGC 9对表型变异的贡献率分别为12.61%和10.85%。共检测到与水稻发芽率相对碱害率相关的QTL 6个，对表型变异的贡献率为4.82%～28.07%，其中位于第2染色体RM29-RM221区间的qRGC 2、位于第6染色体RM225-RM204区间的qRGC 6 1、位于第9染色体RM219-RM3700区间的qRGC 9和位于第12染色体RM260-RM3226区间的qRGC 12对表型变异的贡献率较大，分别为28.07％、15.35％、15.61％和18.91％，为主效QTL，但其相应的区间距离均较远，需要进一步深入研究。所检测的QTL增效等位基因主要表现为部分显性和超显性。

Detection of QTL for Alkali Tolerance at the Germination Stage in japonica Rice

The quantitative trait loci (QTLs) for germination capacity and relative alkali damage rate for germination capacity in rice under alkali stress (0. 15% Na_2CO_3 solution) were identified by using an F_(2:3)population, which included 200 individuals and lines derived from a cross between two japonica cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The germination capacity and its relative alkali damage rate showed a continuous and near normal distribution in F_3 lines. Seven QTLs associated with the germination capacity under alkali stress were detected, which explained 4. 05% to 12. 61 % of the observed phenotypic variances. qGC-6 and qGC-9 were located in RM225-RM204 and RM219-RM3700, respectively, which accounted for 12. 61% and 10. 85% of the observed phenotypic variation, respectively. Six QTLs correlated with relative alkali damage rate for germination capacity under alkali stress were detected. qRGC-2, qRGC-6-1 , qRGC-9 , and qRGC-12 were major QTLs located in RM29-RM221, RM225-RM2O4, RM219-RM3700, and RM260-RM3226, respectively, which explained 28.07%, 15.35%, 15.61% andl8.91% of the observed phenotypic variation, respectively. Given the long distances between the markers further research should be conducted. Most of the alleles were partially dominant or overdominant.