吡虫啉对蜜蜂幼虫的室内毒性研究

吡虫啉是目前使用最广泛的新烟碱类农药,其不合理使用破坏蜜蜂的嗅觉记忆能力,影响采集行为,导致多种亚致死效应。利用室内人工饲养蜜蜂幼虫技术,选取意大利蜜蜂幼虫为研究对象,经3 d适应性饲养后,连续3 d喂食含不同浓度的吡虫啉日粮,测定蜜蜂幼虫的存活率、化蛹率和羽化率,评估吡虫啉对蜜蜂幼虫生长发育影响。结果表明,吡虫啉处理剂量为15ng·幼虫~(-1)时,并不影响蜜蜂幼虫存活率、化蛹率和羽化率;当处理剂量达到150 ng·幼虫~(-1)时,蜜蜂幼虫羽化率下降,但不影响蜜蜂幼虫的存活率和化蛹率;幼虫7 d半数致死剂量为2 300 ng·幼虫~(-1)。高剂量吡虫啉对蜜蜂幼虫存活率、化蛹率和羽化率均存在影响,处理剂量越高,存活率、化蛹率和羽化率越低,呈高度负相关(r=-0.99,-0.94,-0.89),同时蜜蜂幼虫的羽化时间延长。研究可为吡虫啉的合理使用提供科学参考。

Indoor Toxicity Research of Imidacloprid on Honeybee Larvaes

Imidacloprid is the most widely used neonicotinoids in the world. Researches showed that it could destroy the olfactory memory ability of bees, influence their acquisition behavior and cause a variety of sublethal effects. In this paper, the Apis mellifera larvae was selected as test organisms and indoor artificial feeding technique was adopted to evaluate the impact of imidacloprid on the development of honeybee larvae. After three days of adaptive breeding, larvae were fed with diet with different concentrations of imidacloprid for 3 days. Then the survival rate, pupation rate and eclosion rate were determined. Results showed that: no significant effects of survival rate, pupation rate and eclosion rate were observed under the dose of 15 ng imidacloprid per larva, but when treated with imidacloprid of 150 ng per larva, the eclosion rate significantly decreased, while the survival rate and pupation rate did not change obviously. The calculated 7 d-LD₅₀ of imidacloprid is 2 300 ng per larva. High doses of imidacloprid could influence the survival rate, pupation rate and eclosion rate of bee larvae. The higher the dose, the lower the survival rate, pupation rate and eclosion rate, with the r coefficients of -0.99, -0.94 and -0.89 respectively. Meanwhile, the delay of feather was also observed under high dose. The results could provide reference for the reasonable use of imidacloprid.