陆地棉杂种F_(2)代优势组合的筛选研究

Selection Crosses with Heterosis for F_(2)Generation of Hybrids in Upland Cott on(G.hirsutum L.)

采用不完全双列杂交设计 ,以高产抗病推广品种作亲本选配杂交组合 ,进行随机区组试验 ,结果表明皮棉产量加×加上位性方差达 5%显著水平 ,显性方差达 10 %显著水平。皮棉产量加×加上位性效应值以苏棉 4号和中棉所 19为高 ,它们具有较高的一般配合力 ,皮棉产量显性效应值最高的是泗 331,因此它也具有较好的特殊配合力。F2 基因型及杂种优势估计值与预测值之间的相关系数说明根据亲本及 F1数据用 ADAA模型预测F2 代基因型值及杂种优势是可行的。除单株铃数外 ,其余产量性状及纤维品质性状都有组合表现了群体超亲优势。组合 ( 2× 5)皮棉产量 HPB( F2 )为 2 2 .36% ,达显著水平。超亲优势利用代数最多的是组合( 3× 5)的籽棉产量性状 ,可用 4 .52 51代。群体超亲优势两年平均超过 5%的组合是 ( 1× 5)和 ( 2× 5)

The MINQUE(1) procedures were used for estimating variance components and geneti c effects by analyzing diallel crosses of Upland Cotton with ADAA and ADAA. Envi ronment interaction models,genotype value and heterosis of F 2 generation were then predicted. Dominant variance and additive×additive variance were significant at 0.10 and 0.05 probability level in lint yield. Significant correlation coefficients between observed and expected genotype values and heterosis for F 2 generatio n indicated that ADAA model was adaptable in prediction based upon data of paren ts and F 1 hybrids. Heterosis over mid parent value based on population mean was observed in most of the economic important traits. Five crosses showed heterosis over better pa rent in both seed cotton yield and lint yield, H PB (F 2) was also obtain e d in other yield, yield component traits,and fiber quality traits except for bol l number. The number of generations still having heterosis was 4.5251 in cro ss (3×5) for seed cotton yield.