水菖蒲活性物质β-细辛醚对四种储粮害虫的熏蒸活性

Fumigant toxicity of β-asarone extracted from Acorus calamus against four stored grain beetles

植物性次生物质在植物-害虫的关系中起着非常重要的作用,植物中的一些成分对害虫具有熏蒸、触杀和驱避等作用。水菖蒲Acorus calamusL.是一种常用中药,它的主要杀虫活性成分为β-细辛醚。本研究通过室内生测试验研究了水菖蒲根茎提取物β-细辛醚对玉米象Sitophilus zeamaisMotschulsky、谷蠹Rhyzopertha dominica(Fabricius)、赤拟谷盗Tribolium castaneum(Herbst)和四纹豆象Callosobruchus maculatus(Fabricius)4种储粮害虫的熏蒸击倒和致死作用。结果表明:β-细辛醚对4种试虫的熏蒸击倒和致死作用明显。以50μL/L的浓度处理120h后,对玉米象、谷蠹和四纹豆象的击倒作用均达到100%,而对赤拟谷盗击倒率为50%;玉米象、谷蠹和四纹豆象的死亡率分别为81.23%,97.78%和100%,而赤拟谷盗死亡率仅为8.89%。处理24h,β-细辛醚对玉米象、谷蠹、赤拟谷盗和四纹豆象的KC50分别为49.38,102.96,124.04和1.07μL/L;处理120h,β-细辛醚对玉米象、谷蠹、赤拟谷盗和四纹豆象的LC50分别为17.82,4.42,116.48和0.73μL/L。结果显示水菖蒲根茎提取物β-细辛醚对4种储粮害虫均具有明显的熏蒸效果,具有开发为储粮害虫熏蒸剂的潜力。

Plant secondary metabolites play important roles in plant-insect relationships. Some plant-based extracts are insect repellents or have fumigant or contact toxicity. β-asarone is the main active ingredient of Acorus calamus L., a commonly used Chinese traditional medicinal herb. In this study, the knockdown and lethal impacts of β-asarone on four main stored-grain insects, Sitophilus zeamais, Rhyzopertha dominica, Tribolium castaneum and Callosobruchus maculatus were assayed in the laboratory. The study results showed that β-asarone extracted from A. calamus rhizome had significant knockdown and lethal impact on the pests. After the pests were treated with β-asarone for 120 h at the concentration of 50 μL/L, 100% of the C. maculatus, S. zeamais and R. dominica adults, and 50% of T. castaneum adults were knocked down; the mortality rates of T. castaneum, S. zeamais, R. dominica and C. maculatus adults were 8. 89%, 81.23% , 97.78% and 100% , respectively. After 24 h exposure, the KCs0 values for S. zeamais, R. dominica, T. castaneum and C. maculatus adults were 49. 38, 102. 96, 124. 04 and 1. 07 μL/L, respectively. After 120 h exposure, the LC50 values for S. zeamais, R. dominica, T. castaneum and C. maculatus adults were 17.82, 4.42, 116.48 and 0.73 μL/L, respectively. It is so concluded that theβ- asarone extracted from A. calamus has distinct fumigant toxicity against all the four pests assayed, and thus can be exploited as a potential fumigant.