苯并噻唑对不同虫态韭菜迟眼蕈蚊的生物活性

【目的】明确室内条件下挥发性化合物苯并噻唑对韭菜迟眼蕈蚊Bradysia odoriphaga Yang et Zhang的生物活性。【方法】采用三角瓶密闭熏蒸法测定了苯并噻唑对韭菜迟眼蕈蚊成虫、 卵、 幼虫和蛹的熏蒸活性； 利用Oxytherm氧电极研究了苯并噻唑对韭菜迟眼蕈蚊成虫呼吸速率的影响； 利用“Y”型嗅觉仪测定了韭菜迟眼蕈蚊成虫对苯并噻唑的行为反应。【结果】苯并噻唑对雌雄成虫处理0.5~2.0 h的LC50分别为0.186~0.052和0.163~0.039 μL/L； 在0.01~0.13 μL/L剂量下对卵熏蒸处理24 h， 第6 天卵孵化率为4.83%~82.39%， 而对照组孵化率为96.97%； 苯并噻唑熏蒸4龄幼虫6~72 h的LC50变化范围为1.247~0.248 μL/L； 0.01~0.09 μL/L剂量熏蒸蛹24 h， 第5天的羽化率为8.17%~69.63%， 对照组羽化率为96.23%。用0.052和0.039 μL/L浓度分别处理雌雄成虫测定2.5 h内呼吸速率的变化， 表现为处理组初始呼吸速率明显高于对照组， 然后逐渐降低至与对照组持平， 最后明显低于相同处理时间对照组呼吸速率。“Y”型嗅觉仪测定结果表明， 苯并噻唑对韭菜迟眼蕈蚊成虫有较强的引诱作用。在0.5 L/min空气流速条件下， 0.5 μL的苯并噻唑对雌雄成虫的引诱率分别为88.33%和78.33%。【结论】苯并噻唑对韭菜迟眼蕈蚊各虫态有很好的毒杀效果， 并对成虫有强烈的引诱作用。

Biological activity of benzothiazole against Bradysia odoriphaga (Diptera: Sciaridae) at different developmental stages

【Aim】 The biological activity of benzothiazole on Bradysia odoriphaga Yang et Zhang was assessed in the laboratory. 【Methods】 The biological activity of benzothiazole against adults, eggs, larvae and nymphs of B. odoriphaga was detected with fumigation method, the inhibition of benzothiazole on the respiratory rate of B. odoriphaga adults was tested with an Oxytherm system, and the behavioural response of B. odoriphaga adults to benzothiazole was measured with Y-tube olfactometer. 【Results】 The results showed that the LC50 values of benzothiazole against female and male adults were 0.186-0.052 and 0.163-0.039 μL/L at 0.5-2.0 h after treatment, respectively. After fumigation with 0.01-0.13 μL/L benzothiazole for 24 h, the egg hatching rate of B. odoriphaga at 6 d after treatment was 4.83%-82.39%, while that of the control was 96.97%. The LC50 value of benzothiazole against the 4th-instar larvae at 6-72 h after treatment was 1.247-0.248 μL/L. After fumigation with 0.01-0.09 μL/L benzothiazole for 24 h, the eclosion rate of pupae was 8.17%-69.63% at 5 d after treatment, and that of the control was 96.23%. After the female and male adults were treated with 0.052 and 0.039 μL/L benzothiazole for 2.5 h, respectively, their respiratory rates were higher than that of the control group first, then decreased to the comparable level of the control group, and finally were significantly lower than that of the control group. Benzothiazole also showed good luring activity to adults, and the attraction rates to female and male adults were 88.33% and 78.33% at the dose of 0.5 μL at 0.5 L/min air velocity, respectively. 【Conclusion】 Benzothiazole has strong fumigation toxicity to B. odoriphaga at various developmental stages and distinct luring activity to its adults.