利用籼粳交RIL群体对水稻耐寒性及再生力的QTL分析

 以粳糯稻糯89 1与籼稻蜀恢527构建的籼粳交F7代RIL群体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。在5℃低温条件下，对亲本及RIL群体进行芽期耐寒性鉴定；在冬季自然低温条件下，对亲本及RIL群体进行再生稻桩越冬耐寒性鉴定；对亲本及RIL群体进行再生力鉴定。利用SSR标记对水稻耐寒性、再生力进行QTL检测。结果表明，水稻耐寒性和再生力在RIL群体呈连续分布，表现为数量性状遗传特征。共检测到控制芽期耐寒性的QTL 2个(qCtg3、qCtg5)，分布在第3和第5染色体上，对表型变异的贡献率分别为75.57%和79.04%；检测到控制再生稻桩越冬耐寒性的主效QTL 1个（qCtr5），在第5染色体上；检测到控制再生力的QTL 2个（qRa4、qRa5），分布在第4和第5染色体上，对表型变异的贡献率分别为8.17%和7.09%。qCtg5、qCtr5和qRa5同时与第5染色体上标记RM153连锁，在分子水平上表明水稻芽期、越冬耐寒性与再生力具有相关性。

QTL Analysis of Cold Resistance and Ratooning Ability by Using indica-japonica RIL Populations in Rice

A molecular linkage map containing 105 SSR markers was constructed by using a RIL population which was derived from the F7 descent of a cross between japonica glutinous rice variety Nuo 89 1 and an indica variety Shuhui 527. The cold resistance of bud for both the parents and the RIL was investigated at 5℃ low temperature, and  their survival and ratooning ability were evaluated under natural temperature conditions in winter. QTL analysis showed that the cold resistance of rice was controlled by QTLs and followed a continuous distribution in RIL population. Two QTL,  qCtg3  and  qCtg5， controlling cold resistance at bud stage were located on chromosome 3 and 5, explaining 7557% and 79.04% phenotypic variation, respectively. A major QTL, qCtr5， controlling the survival and ratooning ability in rice was mapped on chromosome 5. Two QTLs(qRa4, qRa5) conferning ratooning capacity were  detected on chromosome 4 and 5, explaining 8.17% and 7.09% phenotypic variation, respectively. qCtg5， qCtr5  and  qRa5 locus were simultaneously linked to RM153 on chromosome 5, which indicated the relationship of those traits.