转基因玉米2HVB5的性状鉴定及遗传稳定性分析

为了明确转基因玉米2HVB5的目标性状及遗传稳定性，对回交转育郑58的BC₅S₁、BC₅S₂代转基因玉米2HVB5分别进行了Southern blot、ELISA、室内和田间生物活性测定、靶标除草剂草铵膦耐受性分析及农艺性状调查。结果显示，2HVB5中目的基因cry2Ah-vp和bar都是以单拷贝的形式整合到玉米基因组并稳定遗传，Cry2Ah-vp和PAT蛋白在2HVB5植株的不同时期、不同组织部位均有表达，其中在叶片中的表达量相对较高，分别达到2-3.5 μg/g FW（鲜重）和8-17 μg/g FW（鲜重）。室内生物活性检测结果表明，2HVB5转基因玉米对东方粘虫和棉铃虫有很高的抗性，接虫后4-5 d幼虫死亡率达100%，对草地贪夜蛾有明显的体重抑制。田间抗虫性鉴定结果也表明，2HVB5转基因玉米对东方粘虫和棉铃虫均达到高抗水平，平均抗性级别分别为1.19-1.29和0.60-0.73。2HVB5转基因玉米可耐受田间使用中剂量4倍量的草铵膦，农艺性状与对照郑58相比无显著差异。转基因玉米2HVB5遗传稳定，高抗虫耐除草剂，可用于玉米害虫尤其是夜蛾科害虫的防治，具有产业化应用前景。

Identification of Target Traits and Genetic Stability of Transgenic Maize 2HVB5

In order to confirm the target traits and genetic stability of transgenic maize 2HVB5，Southern blot, ELISA, bioassay in laboratory and field, target herbicide-tolerance analysis and agronomic traits investigation were carried out on BC₅S₁ and BC₅S₂ transgenic maize 2HVB5 plants which had been backcrossed to Zheng 58. The results showed that the target genes cry2Ah-vp and bar were integrated into maize genome in the form of single copy and steady inheritance in 2HVB5 plants. Cry2Ah-VP and PAT proteins were expressed in different stages and different tissues in 2HVB5 plants, and the expressions in the leaves were relatively high, reaching 2-3.5 μg/g fresh weight（FW）and 8-17 μg/g FW respectively. The bioassay results in laboratory showed that 2HVB5 plants had high resistance to armyworm（Mythimna separate）and cotton bollworm（Helicoverpa armigera）， the corrected mortality rates of armyworm and cotton bollworm larvae reached 100% on 4-5 d, and the 2HVB5 plants presented a significant weight inhibiton to fall armyworm（Spodoptera frugiperda）. The bioassay results in field also showed that 2HVB5 plants had high resistances to armyworm and cotton bollworm, the average resistance indexes were 1.19-1.29 and 0.60-0.73， respectively. The transgenic maize 2HVB5 tolerated 4 times the recommended medium dose for glufosinate application in field, and there were no significant differences in agronomic traits compared with the control Zheng 58. These indicate that transgenic maize 2HVB5 is of genetic stability and high insect resistance and herbicide resistance. It can be used for the control of corn pests, especially Noctuidae pests, and has a prospect of commercial application.