7个粳稻SSR和SRAP分子标记遗传距离比较及其与产量性状杂种优势的关系

本研究选用产量性状有显著差异的7个粳稻品种,按照Griffing双列杂交方法Ⅳ配制21个杂交组合,用SSR和SRAP分子标记分析亲本遗传距离及其与粳稻产量性状杂种优势问的关系,并比较分析两种分子标记在估算遗传距离时的差别.结果表明,每对SSR引物产生1～11条多态性带,平均3.8条,而每对SRAP引物组合产生1～15条多态性带,平均5.2条.SRAP引物所扩增的条带数和多态性何点数分别是SSR引物的3.3倍和1.3倍.两种分子标记对遗传相似系数较小的品种进行聚类分析时可获得一致的结果,但对遗传相似系数较大的品种进行聚类分析时所得结果并不一致;粳稻产量性状杂种优势的表现大小因件状和杂交组合不同而异;F_1杂种产量性状的表现与亲本自身的性状特点和互补关系密切,用SSR和SRAP分子标记遗传距离难以预测粳稻杂种后代的产量表现和杂种优势强弱.

Comparison of Genetic Distance among Seven Cultivars of Japonica Rice Based on SSR and SRAP and its Relationship with Heterosis of Yield Traits

In this research, we employed seven cultivars of japonica rice with significant differences in yield traits to be as materials, and made twenty-one hybrid combinations according to Griffing dialed mating system Ⅳ. We analyzed the genetic distances of the test materials based on SSR and SRAP markers and its relationship with heterosis of yield traits, compared and analyzed the difference of genetic distances estimated by using SSR and SRAP markers. The results showed that the number of bands produced per pair of SSR primers ranged from one to eleven, with an average of 3.8 bands per primer, similarly, which of each pair of SRAP primers produced one to fifteen bands,with an average of 5.2. bands per primer. The number of bands and polymorphic locus amplified by using SRAP marker were 3.3 times and 1.3 times more than that of SSR marker, respectively. The cluster analysis of tested lines with low genetic similarity by using SSR and SRAP, which results were coincident, while in the lines with high genetic similarity the situation is quite the reverse. The heterosis of yield traits in japonica rice was up to yield traits and hybrid combination; the yield traits of hybrid F_1 depends on the characteristics and complementary advantages of parents, therefore it is unsuitable to predict the yield and heterosis of hybrid progeny through genetic distance of parents which estimated by using SSR and SRAP markers.