玉米转Bt基因自交系的抗玉米螟特性鉴定初报

Primary Study on Identification of Corn-borer Resistance in Corn Inbred-lines Transferred with Bt Gene

通过田间接卵和室内PCR分子检测 ,对采用回交法育成的Mo17Bt、4 78Bt、综 3Bt和 87 1Bt等 4个转Bt基因自交系的抗虫性以及Bt基因的存在 ,进行鉴定。结果表明 ,4个转基因自交系群体的抗虫性明显提高 ,虫孔隧道长度比阴性对照平均缩短 4 9.70 % ,差异达显著水平 ,但抗虫性不如阳性对照 ;群体内 ,单株间抗虫性仍存在差异 ,有高抗到高感不同类型 ,其中抗虫株的虫孔隧道长度比阴性对照平均缩短 78.4 0 % ,达极显著水平。 4种转基因自交系均含有Bt基因 ,扩增出小于 10 0bp的DNA片段。已选出既含有Bt基因、田间抗虫性表达又较明显的自交系 ,为进一步进行抗虫转基因杂交种的选育 ,奠定了基础。

Using both inoculation of corn borer eggs in the field and PCR molecular test in laboratory, the corn borer resistance and the existence of Bt gene were identified in four corn inbred lines transferred with Bt gene. The results showed that the resistance to corn borer of the four transgenic inbred lines was increased obviously and the mean of worm tunnel length was significantly decreased by 49.71% compared with the negative controls, but the resistance level was not high as the positive control. Within each population of the four inbred lines, the resistance varied from high level of resistance to high level of sensitivity. Comparing with the negative controls, the tunnel length of the resistant plants was significantly decreased by 78.40%. DNA fragments specific for the Bt gene were detected from the four inbred lines by PCR. The inbred lines with Bt gene and high resistant to corn borer were selected. These inbred lines would facilitate breeding corn hybrid with Bt gene.