Key Laboratory of Pollinating Insect Biology, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, China.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
J Econ Entomol. 2021 Feb 9;114(1):403-408. doi: 10.1093/jee/toaa261.
Cry78Ba1 is Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) (Bt) protein found with high insecticidal activity against the piercing-sucking insect Laodelphax striatellus Fallén (Homoptera: Delphacidae) and has broad application prospects for control of the rice planthopper. As honey bees may be exposed to Bt Cry78Ba1 rice pollen by feeding, we evaluated the risk of Bt Cry78Ba1 toxin to Apis mellifera L. workers. A dietary exposure experiment was conducted on worker larvae and adults under controlled laboratory conditions to examine the effects of Cry78Ba1 toxin on honey bees. Worker bee larvae were fed a diet containing Cry78Ba1 toxin (0.01, 0.1, 1, and 10 mg/liter) on day 2 through day 5 after grafting, and adults were exposed to syrup containing Cry78Ba1 for up to 16 d. Negative control (no test substance added), solvent control (1 mM Tris-HCl), and positive control (dimethoate 45 mg/liter for the larva test, 1 and 45 mg/liter for the adult test) groups were established. Compared with the negative control, larvae and adults that consumed food containing Cry78Ba1 toxin exhibited no significant differences in survival, larval weight, or pollen or syrup consumption. This result indicates that chronic oral exposure to Cry78Ba1 toxin has no negative effects on honey bees at the maximum tested concentration.
Cry78Ba1 是苏云金芽孢杆菌 Berliner（芽孢杆菌目：芽孢杆菌科）（Bt）蛋白，对刺吸式昆虫褐飞虱（同翅目：飞虱科）具有高杀虫活性，在防治稻飞虱方面具有广阔的应用前景。由于蜜蜂可能通过取食而接触到 Bt Cry78Ba1 稻花粉，因此我们评估了 Bt Cry78Ba1 毒素对意大利蜜蜂（Apis mellifera L.）工蜂的风险。在受控实验室条件下，对幼虫和成虫进行了饮食暴露实验，以研究 Cry78Ba1 毒素对蜜蜂的影响。工蜂幼虫在嫁接后第 2 天至第 5 天通过饮食摄入含有 Cry78Ba1 毒素（0.01、0.1、1 和 10 mg/L）的饮食，而成虫则最多暴露于含有 Cry78Ba1 的糖浆中 16 天。设立了阴性对照（未添加测试物质）、溶剂对照（1 mM Tris-HCl）和阳性对照（幼虫试验中添加 45 mg/L 的乐果，成虫试验中添加 1 和 45 mg/L 的乐果）。与阴性对照组相比，食用含有 Cry78Ba1 毒素的食物的幼虫和成虫在存活率、幼虫体重或花粉或糖浆消耗方面没有显著差异。这一结果表明，在测试的最大浓度下，慢性口服接触 Cry78Ba1 毒素对蜜蜂没有负面影响。
