施氮量对抗虫棉Bt蛋白表达和降解的影响

Effects of Nitrogen Fertilizer Rates on Expression and Degradation of Bt-protein in Transgenic Cotton

在大田条件下,研究了施氮量(高氮450 kg/hm2、中氮225 kg/hm2和CK 0 kg/hm2)对抗虫杂交棉Bt蛋白表达和降解的影响。结果表明,施氮量对叶片和棉铃中Bt蛋白的表达与降解以及产量有一定的影响。在叶片展开期、功能期和衰老期,Bt蛋白表达量表现为中氮处理>高氮处理>CK,至脱落期,其残留量也表现为相同的趋势。其中,在展开期、功能期、衰老期和脱落期,CK叶片中的Bt蛋白含量分别比中氮处理下降了71.22%,79.26%,72.49%,59.08%。在棉铃膨大期和充实期,铃壳、棉纤维和棉籽中Bt蛋白表达量均呈现高氮处理>中氮处理>CK的趋势,至开裂期,棉铃各器官中残留的Bt蛋白也与前、中期表现一致。随着施氮量的增加,叶片中的游离氨基酸、可溶性蛋白和全氮总体呈上升趋势。中氮和高氮处理皮棉产量分别比CK增加20.50%和19.82%。综合考虑不同施氮量棉花的产量以及器官中的Bt蛋白的表达和残留状况,在生产上建议抗虫杂交棉采用225 kg/hm2施氮量为宜。

Effects of nitrogen fertilizer rates on expression and degradation of Bt-protein in leaves and bolls was studied using transgenic cotton under field condition.The nitrogen fertilizer rates were 450 kg/ha（high nitrogen）,225 kg/ha（medium nitrogen） and 0 kg/ha（CK）,respectively.The results showed that nitrogen fertilizer rates had a significant regulation role on expression and degradation of Bt-protein and its yield in transgenic cotton.The content of Bt-protein in leaves of expanding stage,functioning stage and senescing stage indicated that medium nitrogen treatmentshigh nitrogen treatmentsCK,and the residue of Bt-protein in leaves of shedding stage showed the same trend.Among which the content of Bt-protein in leaves of expanding stage,functioning stage,senescing stage and shedding stage,CK was 71.22%,79.26%,72.49%,59.08% lower than medium nitrogen.The content of Bt-protein in shell,fiber and seed of bolls showed high nitrogen treatmentsmedium nitrogen treatmentsCK when the boll was expanding stage and filling stage,and the residue of Bt-protein in boll opening stage revealed the same trend as before.The content of free amino acids,soluble protein and total nitrogen in leaves increased with the nitrogen fertilizer rates.The lint yield applied medium nitrogen and high nitrogen were increased by 20.50% and 19.82% than CK,respectively.It was concluded that applying nitrogen 225 kg/ha was benefit to transgenic cotton when cotton yields and the expression and degradation of Bt-protein was concerned.