cryIAc基因在转基因玉米中的遗传规律及对抗虫性影响

Genetic Analysis of cry IAC Gene in Transgenic Maize Plants and Its Effects on Insect-resistance

旨在研究目的基因在转基因植株和后代植株(株系)中的遗传规律及其对转化植株抗虫性的影响。以花粉介导法将cryIAc基因导入玉米自交系‘郑58’和‘昌7-2’,对转化植株及其后代株系进行分子检测和田间抗虫鉴定。结果表明:(1)转化‘郑58’和‘昌7-2’,T1代分别获得转基因植株24和41个,转化率高达20%以上;(2)转基因T2代、杂交F2代及回交1代(B1)的分子检测结果证明,外源基因的遗传符合孟德尔的3∶1、3∶1和1∶1的遗传分离规律;(3)连续多带的分子检测结果还表明,外源基因可稳定遗传并有效表达,表达水平在9.8-14.3 ng/g叶片鲜重之间;(4)抗虫鉴定结果显示,在阴性对照全部感虫情形下,转基因纯合株系仍表现出较高抗虫活性;(5)此外,回交试验结果还证明外源基因通过杂交可传递给下一代;(6)最终经筛选得到SZ003、SZ005、SC001、SC004和SC007五个高抗虫转基因株系。结果表明,花粉介导法是一种高效、快捷的转化方法,cryIAc基因导入玉米自交系植株后赋予和提高了转基因植株的抗虫活性。

In order to analyse the genetic regularity of target genecryIAc in transgenic and their descendant plants（lines）, and to study the effect of target gene on insect-resistant activity of transgenic plants at the same time, this research work was conducted. Firstly,cryIAc gene was transformed into maize inbred ‘Zheng 58’ and ‘Chang7-2’ separately by pollen-mediated transformation method. PCR, Southern, ELISA analysis and bioassay in the field of each generation transgenic plants were then conducted according to experimental requirements. Results showed that ⑴ A total of 24 and 41 transgenic plants were obtained through transformedcryIAc gene into maize inbred ‘Zheng 58’ and ‘Chang7-2’, respectively. ⑵ The molecular detection results of transgenic T2, hybridization F2 and backcross B1plants suggested that the segregation of target gene in these lines followed 3∶1, 3∶1 and 1∶1 segregation ratio of the Mendel laws of heredity, respectively. ⑶ The molecular detection results of T1 to T4 transgenic plants（lines）showed that the target gene could stably inherited and expressed effectively, the expression amount of the target gene was from 9.8 to 14.3 ng/gleaf fresh weight. ⑷ Moreover, the results of bioassay in the field indicated that in the case of high insect-susceptibility of negative control line, the transgenic lines still showed highly insect-resistant activity. ⑸ In addition, the target gene integrated into genomics of transgenic plants could inherit to the next generation plants by hybridization. ⑹ At last, 5 high insect-resistant transgenic lines, SZ003, SZ005, SC001, SC004 and SC007, was gained by screening. The pollen-mediated transformation method was a effective and shortcut tool used in plant transformation,cryIAcgene could confer and enhance insect-resistant activity of transgenic plants（lines） tansfomated with it.