关键词: Bt蛋白表达; 氮代谢; 相关性; 抗虫棉; Bt蛋白表达; 氮代谢; 相关性

Abstract: [Objective] This study aimed to determine the relationship between Bt protein expression levels and nitrogen metabolism in insect-resistant transgenic cotton lines with different genetic backgrounds and to provide some recommendations for the selection of highly insect-resistant cotton cultivars. [Method] Bt protein contents and nitrogen metabolism-related indexes were measured in young leaves, buds, and bolls of 41 cotton lines at different developmental stages (4–6 leaf, flourishing bud, and flourishing boll setting stages), and the correlations among these indexes were analyzed. [Result] The expression level of Bt protein in vegetative organs was found to be highly significantly positively correlated with the contents of soluble protein and free amino acids but not that of total nitrogen. Bt protein expression levels in reproductive organs were highly significantly positively correlated with soluble protein and total nitrogen contents and significantly positively correlated with free amino acid content. While soluble protein levels showed a relatively steady decrease from seedling to bud stages and from bud to boll setting stages, the highest Bt protein contents were measured in reproductive organs in mid- to late periods. [Conclusion] The expression level of Bt protein had the highest positive correlation with soluble protein and can thus be used as a reliable index for selection of highly insect-resistant cotton cultivars.

Key words: insect-resistant cotton; Bt protein expression levels; nitrogen metabolism; correlation; insect-resistant cotton; Bt protein expression levels; nitrogen metabolism; correlation