大麦杂种F_1的表现及其与亲本的相关性研究

Study of Performances of Barley Hybrid F_1and Correlated with Its Parents

2001年以大麦的7个细胞质雄性不育系的保持系、4个恢复系及其28个杂种F1为材料,2002年以5个细胞质雄性不育系的保持系、5个恢复系及其25个杂种F1为材料,研究杂种F1株高、穗长、穗下节间长、每株穗数、每穗粒数、每株粒数、千粒重、每株粒重、每株干重、籽粒蛋白质含量和赖氨酸含量11个数量性状的表现及其与亲本的相关关系。结果表明:所用亲本在多数性状上都存在显著的遗传差异;除营养品质性状外,杂种F1主要的农艺性状和产量性状普遍存在超高亲优势;多数性状的F1平均值与雌、雄亲本平均值的复相关程度小于疏远程度,表明难以从雌、雄亲本的表现准确预测F1的表现。对相关和疏远的遗传学意义以及改进从亲本预测杂种精度的方法作了简要的讨论。

The performances of barley hybrid F_1 correlated with its parents for 11 quantitative traits, including plant height, spike length excluding awns, inter-node length below spike, spikes per plant, kernels per spike, kernels per plant, kilo-grain weight, kernel weight per plant, dry matter weight per plant, protein content and lysine content in kernels, were investigated in two field experiments: one was composed of 7 CMS maintainers, 4 restorers and their 28 F_1hybrids in 2001, and another composed of 5 CMS maintainers, 5 restorers and their 25 F_1 hybrids in 2002. The results showed that most traits had significant genetic difference among parents, and, the superiority over high-parent existed in F_1hybrids for the agronomic and yield traits except nutritional ones. However, the multiple correlation degree of the average of F_1with that of its male and female parents was less than the alienation degree in most traits. The result suggests that it should be difficult to precisely predict the performance of F_1from the phenotypes of its male and female parents. The genetic meaning for the correlation and alienation among hybrid and its parents, and the methodological improvement for predicting the heterosis were also briefly discussed.