本文以4个品种(系)的完全双列杂交为材料,研究了陆地棉幼苗NRA 的配合力及基因作用性质,并探讨了 NRA 与后期重要经济性状的关系。试验结果表明,NRA 主要以加性基因作用为主,显性效应也明显存在,表现部分显性,狭义遗传力较高。在所研究的亲本中,NRA 正负效应基因比例分布不均;隐性基因比例较高,幼苗 NRA 与衣分率有极显著的正相关,与单铃重有显著的负相关,与其它重要经济性状如种子生化品质和纤维品质相关不明显。在陆地棉中,幼苗 NRA 作为生化育种指标存在其局限性。 In this study, the complete races of four varieties (lines) were used as materials to study the combining ability and gene-acting properties of NRA in Upland cotton. The relationship between NRA and important economic traits was also discussed. The experimental results showed that NRA was mainly dominated by additive genes, and the dominant effect was also obvious. The expression was partly dominant and the narrow sense of heritability was high. Among the parents studied, the distribution of NRA positive and negative genes was unevenly distributed, and the proportion of recessive genes was high. There was a significant positive correlation between NRA and lint percentage of seedlings, negatively correlated with single boll weight, and other important Economic traits such as seed biochemical quality and fiber quality are not obvious. In G. hirsutum, seedling NRA has its limitations as a biochemical breeding index.