转基因抗虫玉米对亚洲玉米螟生长发育和实验种群增长的影响

Influences of Transgenic Bt Corn on the Growth and Development and Population of Asiatic Corn Borer

以两个转Bt抗虫基因玉米品系G03-2396、G03-2739和1个常规对照品种苏玉16为材料，研究其对亚洲玉米螟幼虫生长发育和实验种群消长动态的影响。结果表明：①两个转基因玉米材料的心叶组织对玉米螟低龄幼虫的毒性很强，1龄幼虫取食这两个转基因玉米心叶组织后8d死亡率超过97％；2龄幼虫取食心叶组织8d后死亡率超过80％；1-4龄幼虫或全部死亡不能化蛹，或平均蛹重与对照品种相比显著降低，仅5龄幼虫各测定指标与对照品种相比差异不显著；两个转基因玉米材料的雌穗组织对玉米螟幼虫的毒性较低，即使低龄幼虫取食8d后的死亡率与对照苏玉16相比差异也不显著。②玉米螟高龄幼虫取食两个转基因抗虫玉米心叶后，存活的部分幼虫化蛹羽化后的成虫寿命明显缩短，单雌产卵量显著下降，甚至卵的孵化率也有所降低。表明所选的两个转成基因玉米品系对玉米螟的毒性具一定的后续效应。

Two Bt transgenic corn cultivars G03-2396 and G03-2739, and a conventional corn cuhivar Suyu 16 were used as materials to study their influences on the growth and development and population dynamics of the Asiatic corn borer in the laboratory. Resistances of whorl leaves of two transgenic Bt corn cultivars to the small instar larvae of Asiatic corn borer were very high, the mortality of the first instar larvae eating whorl leaves over 97 % eight days later, and the mortality of the second instar larvae over 80%. The first to the fourth instar larvae either entirely died and couldn＇ t pupate, or the average pupa weight was significantly lower than the control. Resistances of ears of the two transgenic Bt corn euhivars to the Asiatic corn borer were as low as Suyu 16（CK）. After the elder larvae ate whorl leaves of these two transgenic Bt corn cultivars, the adult longevity was significantly shortened, the eggs laid per female were evidently less, and eggs hatching rate droped. Results indicated that there were subsequent effects on the pupa and adult of Asiatic corn borer eating transgenic Bt corn cultivars.