Potential of soybean crosses in early inbreeding generations for grain yield

Abstract The present study aimed to evaluate the combining ability of 16 soybean genotypes using a partial diallel. Two experiments were carried out to estimate the general (GCA) and specific (SCA) combining ability, one with 64 crosses and the other with 16 parents. At the R8 stage, F2 plants and the parents were evaluated for the following traits: number of days to flowering (NDF), number of days to maturity (NDM), plant height at maturity (PHM), and grain yield (GY). Results indicated genetic variability between the parents and between the crosses. For GY, six (37.5%) parents stood out with high yield. The GCA and SCA estimates were significant for all traits, revealing additive and non-additive effects. The parent USP 04-17.027 (4) was superior for presenting the highest means, heritability, and GCA. The cross (4x13 = USP 04-17.027 x USP 231-2224-12) stood out owing to the highest SCA for GY.

摘要
本研究旨在通过部分双列杂交（partial diallel）试验，评估16个大豆基因型的配合力。本研究开展两项试验以估算一般配合力（general combining ability, GCA）与特殊配合力（specific combining ability, SCA）：其一包含64个杂交组合，其二包含16个亲本。在大豆R8生育期，对F₂植株及亲本的以下性状进行观测：开花天数（number of days to flowering, NDF）、成熟天数（number of days to maturity, NDM）、成熟期株高（plant height at maturity, PHM）以及籽粒产量（grain yield, GY）。结果显示，亲本间及杂交组合间均存在遗传变异。针对籽粒产量，有6个（占比37.5%）亲本表现出优异的产量水平。所有性状的GCA与SCA估计值均达显著水平，表明存在加性遗传效应与非加性遗传效应。亲本USP 04-17.027（编号4）表现最优，其性状均值、遗传力及一般配合力均为最高。杂交组合（4×13 = USP 04-17.027 × USP 231-2224-12）因籽粒产量的特殊配合力最高而表现突出。