甘蓝型油菜(Brassica napus L.)杂种优势的改良研究——待改良组合的主位点组分析及供体亲本选择

On Improvement of Heterosis in Rapeseed ( Brassica napus L.)-Analysis of Major Loci Group of Cross Combination to Be Improved and Selection of Donor Parents

应用作物数量性状主位点组分析方法分析了甘蓝型油菜 (BrassicanapusL .)品种“宁杂 1号”的保持系、恢复系与 10个供体亲本间组合的单株种子产量差异 ,估算出代表外源有利基因的遗传参数 μG′值 ,以此作为标准选择供体亲本 ,改良宁杂 1号的杂种优势。单株产量分析结果 ,虽然 10个供体亲本与“宁R1”间杂种组合单株产量的杂种优势明显 ,但 10个供体亲本中只有P6(“宁油 10号”)与“宁B6”间杂交组合产量比宁杂 1号明显提高(7 78% )。这表明通过直接选择恢复系来提高宁杂系统杂种组合的杂种优势的效率有限。 10个供体亲本的单株产量的G位点组效应 (μG′)值分析结果 ,有 3个供体亲本的 μG′值较高 ,达到显著水平 (P <0 0 5 )。这 3个亲本分别为“五十铃”、“苏油 1号”和“中油 82 1” ,它们可使宁杂 1号的单株产量分别获得 2 8 49%、2 9 70 %和 45 6 6 %的提高 ,表明这 3个亲本可作为候选供体亲本来改良宁杂 1号的杂种优势。此外 ,研究结果还显示改良恢复系的配合力是提高宁杂

Seed yield per plant of the maintainer line and restorer line of elite hybrid rapeseed 'Ningza 1'( Brassica napus L.)to be further improved and 10 donor parents were analyzed by applying major loci group method of quantitative trait of crops.μG′ value of G locus group,a genetic parameter,in each donor parent which represents the number of alien favorable gene was estimated μG′ would be used as a criteria for selecting donor parent to improve the heterosis of Ningza 1.Results showed that a remarkable heterosis was observed in all the cross combinations of I 1/P w except for the cross combinations of I 1/P 10 ,and only one cross combinations(I 1/P 6) gave a 7 78%of yield higher than the elite hybrid Ningza 1.There were 3 donor parents whose yield higher than the elite hybrid in the 10 cross combinations of I 2/P w,but they did not result in high heterosis in corresponding cross combinations of I 1/P w.It indicates that direct selection of restorer line to improve heterosis of an elite hybrid is not an efficient way.3 donor parents('Isuzu','Suyou 1' and 'Zhong 821')showed significant( P <0 05) effects of G locus group with the μG′value of 4 73,4 93 and 7 58 respectively.They could be chosen as an idea donor for the improvement of heterosis of Ningza 1.By restorer line improvement,theoretically,they could make seed yield 28 49%,29 70% and 45 66% higher than Ningza 1 respectively.Results demonstrate that improvement of the combining ability of restorer line of an elite CMS hybrid was a reasonable way for the heterosis improvement.