Effects of Genotype and Environment on the Main Components in Cottonseed of Upland Cotton

[Objective] The aim of this study is to investigate the effect of cotton genotypes, growth environment, and their interaction on major components in cottonseeds. [Method] Eleven upland cotton cultivars were planted in 10 different locations in the middle and lower reaches of Yangtze River region as research materials. Cottonseeds were collected to determine the contents of six main components including protein content (PC), oil content (OC), gossypol, phytic acid (PA), α-tocopherol and γ-tocopherol, then the genotypes, environment, and their interaction effects were analyzed accordingly. [Result] The results showed that the genotypes, environment, and their interaction had extremely significant effect on the protein and oil content in cottonseeds. The environment had extremely significant effect on the gossypol and phytic acid content in cottonseed. The genotypes had extremely significant effect on the gossypol content and had significant effect on the phytic acid content in cottonseed, but their interaction was insignificant. The genotype effects of α-tocopherol and γ-tocopherol were not significant, but the environmental effects were significant. The differences of tocopherols between different regions reached the extremely significant level. In addition, protein content and oil content were significantly negatively correlated and the sum of the protein and oil contents remained stably at 75%. [Conclusion] In cotton seed quality breeding, not only the differences in varieties, but also the environment and the interaction between varieties and environment should be considered. The expression of the main components of cottonseed is the result of a combination of genotype and ecological environment.