甘蓝型油菜细胞质雄性不育三交种杂种优势的研究

Heterosis of Cytoplasmic Male-sterile Three-way-crosses Hybrids in Brassica napus L.

甘蓝型油菜细胞质雄性不育系与另一个新的该不育细胞质的保持系杂交,其 F_1是单交种不育系,再与恢复系配制三交种,研究其杂种优势表现和提高杂种制种产量的可能性。结果表明,甘蓝型油菜细胞质雄性不育三交种各主要性状优于各亲本,并达显著或极显著水平;各主要性状的平均优势率、超亲优势率和对照优势率大多为正向优势;在对照为三系强优势组合的情况下,单株实际产量的对照优势率因亲本而异,通过选择配合力强的亲本,有可能选育出正向优势于单交种(三系组合)的三交种。单交种不育系构成产量因素的各性状优势率极其显著,其制种产量可大幅度提高。

Studies on heterosis of cytoplasmic male-sterile three-way-crosses hybrids(B.napus L.)and on the probability of increasing yield of hybrid seed were conducted.The results showed that agronomic char- acters of hybrids F_1dominated that of their parent lines with significant or very significant level,the mean, suppor-parent and check heterosis rates of agronomic characters of hybrids F_1 were postive dominances except that of mean individul plant yield,but it's possible that hybrids F_1 with positive check heterosis rate can be bred if high combining ability parents are applied.The results also indicated that agronomic characters of sin- gle cross hybrid male-sterile line dominated that of original male-sterile line with very significant level,the yield of hybrid seed could be increased by a big margin.