通过分子标记估算遗传距离预测甘蓝型油菜的杂种优势

用甘蓝型油菜4个恢复系、3个保持系及其相应的12个F1代共19份材料，研究SSR和SRAP两种分子标记方法估算的遗传距离与油菜重要性状杂种优势的关系。结果发现，在4个恢复系和3个保持系中，45对SSR引物共扩增出87条多态性条带，25对SRAP引物共扩增出131条多态性条带。基于SSR标记估算的遗传距离与产量杂种优势的相关系数为0.423,决定系数为0.179。基于SRAP标记估算的遗传距离与产量杂种优势的相关系数为0.654 （达到0.05显著水平），决定系数为0.428。基于SSR和SRAP混合数据计算的遗传距离与小区产量杂种优势的相关系数为0.642（达到0.05显著水平），决定系数为0.412。表明SRAP标记对产量杂种优势预测的效果要显著高于SSR标记预测的效果，是目前为止报道的通过鉴定亲本遗传多态性预测油菜杂种优势最为有效的分子标记手段，可作为油菜杂种优势预测的一种有效辅助方法。

Heterosis prediction based on genetic distance estimated by molecular markers in rapeseed

The correlation between genetic distance estimated by SSR and SRAP markers and heterosis of various agronomic traits was analyzed in Brassica napus.The materials consisted of four rapeseed restorer lines,three maintainer lines and their 12 resulting F1hybrids.Results showed that 45 SSR primers generated a total of 87 polymorphic bands and 25 SRAP primers generated a total of 131 polymorphic bands in seven parental lines.Regression analysis revealed that the correlation coefficient between genetic distance and yield heterosis was 0.423 based on polymorphism of SSR markers,whereas it was 0.654 based on polymorphism of SRAP markers,which was significant at 0.05 level.Joint analysis of SSR and SRAP markers revealed a correlation coefficient of 0.642(significant at 0.05 level) between genetic distance and yield heterosis.This indicated that SRAP marker is more efficient than SSR marker for the prediction of yield heterosis,and can be used as an effective measure in marker assistant prediction in hybrid breeding.