转基因玉米表达的Cry1Ab、PAT和EPSPS蛋白对日本通草蛉幼虫的安全风险评估

为评价我国自主研发的转基因玉米表达的Cry1Ab、PAT和EPSPS蛋白对日本通草蛉Chrysoperla nipponensis幼虫生长发育的安全风险,通过将外源蛋白混入日本通草蛉人工饲料中的方法,以加入砷酸二氢钾(KH_2AsO_4)的饲料为阳性对照,研究了日本通草蛉幼虫取食后的生长发育状况。结果表明:日本通草蛉取食含Cry1Ab和EPSPS蛋白饲料的幼虫发育历期、茧期、结茧率、羽化率及成虫体重等生物学参数与取食正常饲料处理相比均没有显著差异;而取食含PAT蛋白饲料的幼虫发育历期和结茧率分别为10.7 d和96.6%,与取食正常饲料的对照11.1 d和89.9%差异显著,即饲料中添加PAT蛋白显著提高了幼虫的存活率和发育速率;取食含KH_2AsO_4饲料的日本通草蛉幼虫不能存活到茧期,说明KH_2AsO_4具有显著的杀虫活性。ELISA检测结果表明,取食了分别添加有3种外源蛋白饲料的日本通草蛉幼虫体内可以检测到相应的Cry1Ab、EPSPS和PAT蛋白,含量分别为2 758.8~5 210.7、35 018.0~54 426.6、16.8~149.8 ng/g。表明转基因玉米所表达的Cry1Ab、EPSPS和PAT蛋白对日本通草蛉幼虫没有显著的不利影响。

The risk assessment of Cry1Ab, EPSPS, and PAT proteins expressed by transgenic corn for Chinese green lacewing Chrysoperla nipponensis larvae

To understand the environmental safety of domestic biotech maize on natural enemies, the impact of Chinese biotech maize events C0030.3.5 expressing Cry1Ab and EPSPS proteins and C0010.1.1 expressing PAT and EPSPS proteins on the development and survival of Chrysoperla nipponensis larvae were assessed through diet incorporation bioassay, i. e. Tier-1 Approach. Diet mixed with potassium arsenate (KH₂AsO₄) was the positive control. The results showed that the biological parameters, including larval duration, pupation rate, pupation stage, eclosion rate, and adult fresh weight of C. nipponensis, had no significant difference between the tested C. nipponensis and the control when the artificial diet contained purified Cry1Ab, EPSPS. However, the larval duration and pupation rate were 10.7 d and 96.6%, respectively, when larvae were fed on diet containing PAT protein, which were significantly shorter and higher than those (11.1 d and 89.9%) of the control. In contrast, the larvae could not develop normally into pupae when they were fed on diet containing KH₂AsO₄, indicating that KH₂AsO₄ was toxic to the larvae. The ELISA results showed that the contents of Cry1Ab, EPSPS and PAT proteins were 2 758.8-5 210.7, 35 018.0-54 426.6, and 16.8-149.8 ng/g, respectively. The results indicated that the Cry1Ab, EPSPS and PAT proteins expressed by biotech maize events C0030.3.5 and C0010.1.1 had no adverse effects on the survival and development of C. nipponensis larvae.