3种熏蒸剂对椰心叶甲的熏蒸效果及寄主切叶的影响

Effects of Three Fumigants on Fumigation against the Coconut Leaf Beetle Brontispa longissima and on Cut Leaves of Host Plant

分别利用磷化钙、3%高效氯氰菊酯烟雾剂(烟魁)和溴甲烷3种熏蒸剂熏蒸处理椰心叶甲[Brontispa longissima(Gestro)]各虫态及散尾葵切叶,观察椰心叶甲各虫态的死亡情况和对散尾葵叶片的影响。结果表明:烟魁使用时灼伤散尾葵切叶,不适合处理散尾葵切叶。其他2种熏蒸剂对切叶没有明显影响,影响熏蒸剂对椰心叶甲各虫态致死的主要因素是熏蒸剂的浓度和熏蒸时间。磷化钙处理而言,其分解为磷化氢气体需要时间,需要熏蒸24h,使用0.3mg/m3即可达到完全杀死椰心叶甲的目的;而对于溴甲烷处理而言,用量相对较大,但熏蒸时间较短,20g/m3的浓度2h才可以满足生产上对椰心叶甲除害的需要。研究结果对处理棕榈植物鲜切叶或苗木有重要的借鉴意义。

Three fumigants, embafume, calcium phosphide and 3% Beta cypermethrin aerosol ＂Yankui＂, were used to fumigate cut leaves of Chrysalidocarpus lutesceus and the coconut leaf beetle Brontispa longissima of various stages at different doses for different durations of time. The 3% Beta cypermethrin aerosol injured all the cut leaves of C. lutesceus as well as B. longissima , and is hence not suitable for the control of the beetle, and the other 2 fumigants, embafume and calcium phosphide, killed the beetle and had no effect on the cut leaves. The mortality rate of B. longissima depended on the application rate of the fumigants and the fumigation duration. It takes quiet a long time for calcium phosphide to decompose into H3P, and B. longissima of various stages was killed only when fumigated with the calcium phosphide at a rate of 0.3 mg/m3 for 24 h, whereas the same result was achieved when embafume was applied at a higher rate （20 mg/m3） for a shorter time （2 h）. These results might be of good use for treatment of cut leaves of palm plants and production of nursery palm plants.