Spodoptera litura (Lepidoptera: Noctuidae), the tobacco cutworm, is an prominent agricultural pest. To reduce the use of chemical pesticides that cause health problems and that leave residue in the environment, some botanical pesticides have been developed. Our research aimed to evaluate the insecticidal efficacy of Acorus calamus L. extract for the control of S. litura under laboratory conditions. After 24 h of topical application, the A. calamus methanolic crude extract showed toxicity against secondary instar S. litura larvae (LD50 ~ 7.438 µg/larva). Chrysin (5,7-dihydroxy flavone), one of the isolated phenolic compounds, showed optimal control efficiency (LD50 ~ 2.752 µg/larva) and showed a reduction in carboxylesterase activities, which have detoxification reduction roles in larvae. Chrysin in the crude extract of A. calamus may be an active compound to control this pest, and it may be applied as an alternative to minimize the usage of chemical insecticides.

中文翻译：

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实验室条件下从菖蒲中分离出的酚类化合物对防治斜纹夜蛾（鳞翅目：夜蛾科）的毒性

斜纹夜蛾（鳞翅目：夜蛾科）是烟草地老虎，是一种突出的农业害虫。为了减少使用会导致健康问题并在环境中留下残留物的化学农药，已经开发了一些植物农药。我们的研究旨在评估菖蒲提取物在实验室条件下控制斜纹夜蛾的杀虫效果。局部应用 24 小时后，菖蒲甲醇粗提物对二龄斜纹夜蛾幼虫表现出毒性（LD50 ~ 7.438 µg/幼虫）。白杨素（5,7-二羟基黄酮）是一种分离的酚类化合物，具有最佳防治效率（LD50 ~ 2.752 µg/幼虫），并显示出羧酸酯酶活性降低，对幼虫具有解毒作用。A. 粗提物中的白杨素。