利用乙基多杀菌素防治初烤烟仓库中的烟草粉螟

Control efficacy of spinetoram against Ephestia elutella (Hübner) in cured tobacco leaf warehouse

为有效控制烟草仓储过程中烟草粉螟对在库烟叶的为害,通过室内生物学测定比较了乙基多杀菌素与高效氯氰菊酯对烟草粉螟老龄幼虫的触杀活性;通过实仓试验,调查了不同浓度的乙基多杀菌素对烟草粉螟老龄幼虫的防治效果及持效期,并进行了实仓防治应用。结果表明:乙基多杀菌素对烟草粉螟老龄幼虫的LC_(50)与LC_(90)分别为0.091 6 mg/L和0.249 2 mg/L,高效氯氰菊酯分别为0.127 4 mg/L和1.854 4mg/L;乙基多杀菌素80 mg a.i/L持效期24 d,40 mg a.i/L持效期18 d,而高效氯氰菊酯750 mg a.i/L的持效期为6 d。与常用的高效氯氰菊酯比较,乙基多杀菌素对烟草粉螟的活性高、防治效果好且持效期长,实仓应用效果也得到了验证。基于烟草粉螟老龄幼虫有爬出烟包的习性,利用乙基多杀菌素进行库区表面处理,在无需直接对烟叶用药的情况下阻断了烟草粉螟在初烤烟仓库内的化蛹和羽化,可大幅度降低仓库内的虫口密度,有效控制初烤烟仓库中的烟草粉螟。

To effectively control the damage of Ephestia elutella（Hübner）on tobacco leaves during warehouse storage, indoor bioassay was conducted to compare the contact activity to old larvae of Ephestia elutella（Hübner） between spinetoram and β-cypermethrin. Warehouse experiments were conducted to investigate the control efficacy and duration of spinetoram on old larvae of Ephestia elutella（Hübner） at different concentrations. The field control effect of spinetoram on the Ephestia elutella（Hübner） in warehouse was also tested. The results showed that the LC_（50） and LC_（90） of spinetoram on old larvae of Ephestia elutella （Hübner） were0.091 6 and 0.249 2 mg/L, and those of β-cypermethrin were 0.127 4 and 1.854 4 mg/L, respectively. The duration of 80 and 40 mg a.i/L spinetoram was 24 and 18 days and that of 750 mg a.i/L β-cypermethrin was 6 days. Comparing with common β-cypermethrin, spinetoram performed effectively in activity, control efficiency and duration, and its efficacy was verified in warehouses. The old larvae of Ephestia elutella（Hübner） usually climbs out of tobacco leaf bales, therefore spinetoram surface treatment in warehouses could prevent Ephestia elutella（Hübner） pupation and eclosion even not applying to tobacco leaves directly. Spinetoram couldsignificantly reduce population density and control Ephestia elutella（Hübner）in cured tobacco leaf warehouses.