Histopathological effects and growth reduction in a susceptible and a resistant strain of Heliothis virescens (Lepidoptera: Noctuidae) caused by sublethal doses of pure Cry1A crystal proteins from Bacillus thuringiensis
Histopathological effects and growth reduction in a susceptible and a resistant strain of Heliothis virescens (Lepidoptera: Noctuidae) caused by sublethal doses of pure Cry1A crystal proteins from Bacillus thuringiensis
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DOI：
10.1080/09583159929811
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发表时间：
1999-06-01
影响因子：
1.4
通讯作者：
Ferré, J
中科院分区：
文献类型：
--
作者：
Martínez-Ramírez, AC;Gould, F;Ferré, J
将两种烟草芽虫Heliothis virescens菌株暴露于亚致死剂量的纯Cry 1A晶体蛋白，其中一种是在实验室中选择的对苏云金杆菌Cry 1Ac晶体蛋白具有抗性（其抗性机制与结合减少无关）的菌株，另一种是未选择的对照菌株。进行组织病理学研究以确定由摄入Cry1Ac引起的上皮损伤。中肠的组织切片后，获得20，40和60分钟的毒素摄入。主要在柱状细胞中观察到组织学变化，并且具有时间依赖性。然而，在两种菌株中观察到基本相同的损伤水平。用Cry1Ac和Cry1Ab进行的毒素摄食试验表明，毒素对敏感品系的幼虫生长和摄食有抑制作用，但对抗性品系的幼虫没有显著影响。由于两种菌株的组织病理学损伤相似，因此似乎抗性幼虫可以更容易地修复（或替代）受损细胞。
Two strains of the tobacco budworm Heliothis virescens, one selected in the laboratory for resistance to Cry1Ac crystal protein from Bacillus thuringiensis (for which the mechanism of resistance was not associated with reduced binding) and an unselected control strain, were exposed to sublethal doses of pure Cry1A crystal proteins. A histopathological study was conducted to determine the epithelial damage caused by ingestion of Cry1Ac. Tissue sections of the midgut were obtained after 20, 40 and 60 min of toxin ingestion. Histopathological changes were observed primarily in columnar cells and were time-dependent. However, essentially the same level of damage was observed in the two strains. Toxin feeding tests with Cry1Ac and Cry1Ab, indicated that the toxins retarded growth and inhibited food intake of susceptible larvae, but did not significantly affect larvae of the resistant strain. Since the histopathological damage was similar in both strains, it appears that resistant larvae could repair (or substitute) more readily the damaged cells.