杀菌剂丙环唑对斜纹夜蛾的毒性

在研究比较了11种农药对斜纹夜蛾Spodoptera litura细胞（简称SL细胞）的毒杀活性基础上，选择毒杀活性最高的杀菌剂丙环唑，对其毒理学机理进行进一步研究。结果表明，丙环唑的细胞毒力最高，在100 μg/mL浓度下处理后48 h，SL细胞的死亡率为98.08％。处理后36 h，丙环唑对SL细胞的LC₅₀值为20.31 μg/mL。丙环唑能明显降低SL细胞的蛋白质含量。以0.5 μg/头的丙环唑注射斜纹夜蛾4龄幼虫，处理后72 h，试虫血淋巴总含量及血细胞数分别下降了26.80％和25.26％；在1.0 μg/头的剂量下，则分别下降了37.67%和36.32%。以0.5 μg/头和1.0 μg/头的丙环唑注射处理后，斜纹夜蛾幼虫体重显著降低。此外，丙环唑能降低斜纹夜蛾幼虫血淋巴含糖量及血淋巴蛋白质含量。在注射处理后96 h和120 h，丙环唑对斜纹夜蛾4龄幼虫的LD₅₀值分别为0.59 μg/头和0.45 μg/头。丙环唑对SL细胞和斜纹夜蛾幼虫均具有较好的毒杀活性，显示出丙环唑类似物控制害虫的可能性。

Insecticidal activities of propiconazole against Spodoptera litura (Lepidoptera: Noctuidae)

On the ground of studying the cytotoxicity of 11 kinds of pesticides, propiconazole, which had the highest toxicity against Spodoptera litura (SL) cells, was chosen to further investigate its toxicology. The results showed that the mortality of SL cells treatment by propiconazole at concentration of 100 μg/mL was 98.08%. The LC₅₀ value of propiconazole against SL cells was 20.31 μg/mL 36 h after treatment. Propiconazole reduced the protein content of SL cells obviously. When injected with propiconazole at concentration of 0.5 μg/larva for 72 h, the blood content and the number of corpuscles of the 4th instar larvae decreased by 26.80% and 25.26% respectively; while at concentration of 1.0 μg/larva, they decreased by 37.67% and 36.32% respectively. Under the both concentrations, the weight of larvae decreased notably. In addition, propiconazole reduced the total sugar and protein content in hemolymph of S. litura larvae. After treatment for 96 h and 120 h, the LD₅₀ values of propiconazole against 4th instar larvae of S. litura were 0.59 μg/larva and 0.45 μg/larva respectively. The high toxicity of propiconazole against cells and larvae of S. litura implied the possibility for propiconazole analog in controlling insect pests.