利用SSR分析滇型杂交稻亲本籼粳分化与杂种优势的关系

Analysis of Relationship between Indica-Japonica Differentiation of Parents and Heterosis in Dian Type Hybrid Rice by SSR Markers

以滇型杂交稻不育系4个、恢复系31个及其组配的31个杂交种为试验材料,利用SSR籼粳特异引物研究亲本籼粳分化程度及与杂种优势的关系。结果表明,在所检测的18个位点上,4个不育系均以粳稻血缘为主,31个恢复系总体上偏粳,但含有不同成分的籼稻血缘,其籼性比率Pi为0～27.8%。亲本SSR遗传距离、籼粳差异与杂种优势相关分析表明,亲本SSR遗传距离与小区产量超父优势等7个性状相关显著;亲本的籼粳分化差异与百粒重超父优势等4个性状显著相关;亲本SSR遗传距离、籼粳差异与小区产量竞争优势相关不显著,说明SSR遗传距离、亲本籼粳分化差异与产量竞争优势无线性关系,但籼粳分化差异适中的亲本杂交,容易得到正向优势极端组合,可从中筛选出杂种优势强的组合。

The relationship between the Indica-Japonica differentiation of parents and heterosis of hybrid rice was studied with 4 sterile lines,31 restoring lines of Dian type hybrid rice and 31 hybrids derived from the sterile lines and restoring lines by using 18 pairs of Indica-Japonica diagnostic primers.The results indicated that in the tested 18 loci,4 sterile lines were Japonica,31 restore lines were Japonica-like but some of tested loci were Indica-like and the Pi was 0-27.8 %. There was a correlation between the Indica-Japonica differentiation of parent detected and genetic distance by SSR markers and some of characters of heterosis of hybrid rice.When certain Indica-Japanica differentiation between parents exists,the percent of combinations with super heterotic hybrid and the mean heterosis of hybrids were high.But that did not mean that more difference of parents led to better heterosis in hybrids,and suitable difference of Indica alleles of parents of extreme heterotic hybrid was 5.6 %.