AFLP标记与水稻杂种产量及产量杂种优势的预测

Using of AFLP Marker to Predict the Hybrid Yield and Yield Heterosis in Rice

利用AFLP分子标记对46个水稻品种进行遗传多样性分析,继而研究分子标记遗传距离与按照NC设计获得的195个杂交组合的产量及特殊配合力的相关性,探讨预测杂种优势的可能性。结果表明:(1)通过UPGMA聚类分析(图3),可将供试材料分为16个类群,并把来源不明的品种(系)划分到相应类群中,从而对这些材料进行初步鉴定。可见,AFLP分子标记是检测类内品种间遗传差异的有效方法,为水稻品种(系)亲本选配提供理论依据。(2)分子标记遗传距离与杂种产量优势、F1产量、特殊配合力之间都呈显著正相关,相关系数介于0.3235-0.7713之间。但相关程度还不足以预测杂种优势。增效座位和减效座位以及使用与杂种优势有关的QTL连锁标记位点可能提高杂种优势的预测能力,但最终解决,将依赖于杂种优势遗传机理的研究。

Genetic diversity among 46 rice clusters was studied using the AFLP molecular marker, and relationship between genetic distance (GD)and hybrid performance in a diallel set of crosses between them was assessed. The results indicated as follows (1) The cluster analysis of the 46 rice cultivars using Unweighted Pair Group Method (UPGMA)showed that the 46 rice cultivars could be classified into eight distinct clusters with subclusters, which contained unknown cultivars (figure 3).Therefore the unknown cultivars could be initially identified. The AFLP molecular marker can be effectively applied in classifying cultivars within the group. The study provides useful information for the selection of parents in the development of rice cultivars and hybrids as well.(2)The correlation (0.3235-0.7713) between genetic distance based on AFLP marker and the hybrid performance、Flgrain yield(F1Y)and specific combining ability(SCA) were positive but not too larger to have a practical utility in predicting hybrid performance. The better correlation would be the preselection of specific markers linked to effect-increasing and effect-decreasing loci and quantitative trait loci (QTL) correlated to heterosis.