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【目的】绿僵菌素（Destruxins）是绿僵菌产生的具有杀虫活性的次生代谢产物，本研究以家蚕Bombyx mori Bm12细胞、亚洲玉米螟Ostrinia furnacalis血细胞（Ofh）、果蝇S2细胞和草地贪夜蛾Sf9细胞为对象，探索绿僵菌素对不同昆虫细胞的毒性差异。【方法】采用MTT法和显微观察法比较绿僵菌素A、B（DA、DB）以及两者等量混合物（DABM）对上述4种昆虫细胞的影响，比较其IC50值和形态学变化。【结果】绿僵菌素处理24 h后，在较低处理剂量（<25μg /mL）下，Ofh细胞比Bm12、S2、Sf9细胞对DA、DB和DABM更为敏感，DA、DB和DABM对Ofh细胞IC50值分别219.19、112.29和34.86μg/mL，而对Bm12、S2、Sf9细胞的IC50值均大于250μg/mL；DA和DB对Ofh细胞具有协同增效作用，对Sf9细胞具拮抗作用，对Bm12和S2细胞具相加作用。显微观察发现，绿僵菌素处理后，6.25μg/mL的低剂量下，即可发现细胞的形态变化，剂量越高，变化越显著。Bm12细胞出现瘤状突起、细胞破碎、聚集、扩展及胞内空泡等现象，且细胞数量减少；Ofh细胞扩展，似乎回归到浆血细胞及类绛色细胞的形态，发生凝集现象，少数出现瘤状突起和细胞破碎；S2细胞出现明显的胞内空泡，少数发生扩展、破碎和聚集现象；Sf9细胞细胞膜收缩、细胞空泡、破碎，细胞数量减少等变化。【结论】玉米螟的血细胞Ofh对绿僵菌素最为敏感，而来自非寄主昆虫果蝇的S2细胞最不敏感。绿僵菌素对4种细胞的致死剂量较高，但引起细胞形态改变的剂量却非常低。“,”Objectives] Destruxins are insecticidal secondary compounds isolated fromMetarhizium anisopliae. In this study, the toxicity of different destruxins was tested on four insect cell lines, i.e.,Bombyx moriBm12,Ostrinia furnacalis hemocytes Ofh,Drosophila melanogaster S2 andSpodoptera frugiperdaSf9. [Methods] MTT and microscopy analysis were employed to evaluated the effects of destruxins A and B (DA and DB), and a 1/1 (m/m) mixture of these compounds (DABM), on the four insect cell lines. Relative toxicity was assessed by comparing IC50s values and morphological changes in the cell lines.[Results]The results indicate that Ofh cells were more susceptible to lower dosages ( 250μg/mL in the other cell types. Furthermore, DA and DB had a synergistic effect on Ofh cells, but an antagonistic effect on Sf9 cells, and an additive effect on Bm12 and S2 cells. Microscopy revealed morphological changes in the different cell lines, even at dosages as low as 6.25μg/ mL. Moreover, these morphological changes became more apparent at higher dosages. Ruptured cells, strumae, aggregation, expanded cells, vacuoles and reduced cell numbers were found in Bm12 cells. In Ofh cells, cells became expanded but appeared to return to normal with aggregation. Vacuoles and a few expanded, ruptured and aggregated cells were found in the S2 cell line, and membrane shrinkage, broken cells and a decrease in cell numbers were recorded in the Sf9 cell line. [Conclusion]TheOfh cell line was the most sensitive to destruxins,and the non-host insectDrosophila melanogaster S2 cell line the least sensitive. The results suggest that although relatively large doses of destruxins are required to kill insect cells, smaller dosages are sufficient to cause changes in cell morphology.