Zhou Mingyuan, Liu Zhenyu, Li Linan, Chen Yuan, Zhang Xiang, Chen Yuan, Chen Dehua
Jiangsu Key Laboratory of Crop Genetics and Physiology, Co-innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou, China.
Front Plant Sci. 2021 May 11;12:623504. doi: 10.3389/fpls.2021.623504. eCollection 2021.
Reproductive organs of transgenic cotton, which contribute to cotton final yield, have low insect resistant efficacy, so it is important to improve their insect resistance. This study was conducted to find out the impact of different urea spray doses on the expression of Cry1A protein in boll shell of Bt cotton (Sikang 1 and Sikang 3), and nitrogen metabolism in this process was also studied to uncover the physiological mechanism. The experiment with six urea doses was organized during peak boll stage in 2017 and 2018. The results showed that urea spray could significantly increase boll shell insecticidal protein contents in both cultivars, with the highest Bt protein content observed at 28-32 kg ha urea dose. In addition, urea spray increased the contents of soluble protein and free amino acid and the activities of GS, GOGAT, GOT, and GPT, but decreased the activities of peptidase and protease in boll shell. Correlation analysis showed that the amount of boll shell Bt protein was positively correlated with levels of soluble protein and amino acid, and activities of GS, GOGAT, GOT, and GPT, but negatively correlated with peptidase and protease activities. Thus, this study demonstrated that higher protein synthesis ability and lower proteolysis ability were related to increased Bt protein content in urea-sprayed boll shell.
转基因棉花的生殖器官对棉花最终产量有贡献，但抗虫效果较低，因此提高其抗虫性很重要。本研究旨在探究不同尿素喷施剂量对Bt棉花（泗抗1号和泗抗3号）棉铃壳中Cry1A蛋白表达的影响，并研究此过程中的氮代谢以揭示其生理机制。在2017年和2018年棉铃盛期进行了六个尿素剂量的试验。结果表明，喷施尿素可显著提高两个品种棉铃壳中的杀虫蛋白含量，在尿素剂量为28 - 32 kg/ha时Bt蛋白含量最高。此外，喷施尿素增加了棉铃壳中可溶性蛋白和游离氨基酸的含量以及GS、GOGAT、GOT和GPT的活性，但降低了肽酶和蛋白酶的活性。相关性分析表明，棉铃壳Bt蛋白量与可溶性蛋白和氨基酸水平以及GS、GOGAT、GOT和GPT的活性呈正相关，但与肽酶和蛋白酶活性呈负相关。因此，本研究表明，较高的蛋白质合成能力和较低的蛋白水解能力与喷施尿素处理的棉铃壳中Bt蛋白含量增加有关。
