不同生态类型甘蓝型油菜在青海生态条件下的杂种优势表现

利用SSR分子标记研究35份不同生态类型甘蓝型油菜品种（系）的遗传多样性,并从中挑选有代表性的6个春性和6个半冬性材料按完全双列杂交方法（Griffing II）组配成66个组合,考查不同生态类型组合的杂种优势,并分析遗传距离与杂种优势的关系。结果表明不同生态类型的35份品种（系）在遗传相似系数0.698处分为5类,第I类主要为春性材料,半冬性材料分布于第II、III、V类,聚类分析结果与材料的生态类型基本一致;春性品种（系）与半冬性品种（系）组配的组合要比同种类型品种（系）间组配的组合具有更强的杂种优势;SSR的分子遗传距离与大多数性状F1表现及杂种优势相关不显著,利用SSR预测杂种优势效果还不明显。

Rapeseed heterosis of different ecotypes in Qinghai province

Genetic diversity of 35 rapeseed （ Brassica napus L. ） accessions including different ecotypes was investigated using simple sequence repeats （ SSRs） markers. Among them,6 spring lines and 6 semi-winter lines were conducted through diallel cross （ Griffing II） mating design for heterosis analysis. The object was to estimate the genetic distance and investigate the relationship between genetic diversity and F1 performance. Results indicated that 35 accessions could be divided into 5 groups at 0. 698 similarity coefficients. The first group included exclusively spring accessions. The semi-winter accessions were grouped into three other groups. The classification of accessions using cluster analysis was generally consistent with ecotypes. Statistic result showed the heterosis of hybrids between different ecotypes was higher than that of the same ecotype accessions. No significant correlation was detected between genetic distance and F1 performance or heterosis in most agronomic traits. It is not appropriate to use the genetic distance evaluated through SSR markers for predicting heterosis in semi-winter and spring type rapeseed.