The present study investigates the effect of gibberellic acid (GA3), a terpenoid and phytohormone, on the digestive physiology and intermediary metabolism of the cotton bollworm Helicoverpa armigera Hübner (Lepidoptera, Noctuidae). Incorporation of GA3 (800 μg g−1 diet) in an artificial diet results in significant reductions in the rates of diet consumption and the efficiency of conversion of food consumption by by H. armigera larvae. The relative growth rate decreases as the concentration increases. The relative α‐amylase activity in sixth‐instar larvae of H. armigera decreases significantly after ingestion of four concentrations of GA3. Histological studies of the midgut in GA3‐treated larvae (800 μg g−1 diet) show degeneration of the epithelial cells. The alanine and aspartate aminotransferase activity decreases at the highest concentration. However, acid phosphatase, alkaline phosphatase, γ‐glutamyl transferase and lactate dehydrogenase activity increase significantly compared with the control. The results clearly demonstrate the adverse effects of GA3 on H. armigera via interruption of nutritional physiology and metabolism.

中文翻译：

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赤霉酸对棉铃虫（Hübner）（鳞翅目：夜蛾科）的拒食和细胞毒活性

本研究调查了赤霉酸 (GA3)，一种萜类化合物和植物激素，对棉铃虫 Helicoverpa armigera Hübner（鳞翅目，夜蛾科）的消化生理和中间代谢的影响。在人工饮食中加入 GA3（800 μg g-1 饮食）可显着降低饮食消耗率和棉铃虫幼虫对食物消耗的转化效率。相对增长率随着浓度的增加而降低。摄入四种浓度的 GA3 后，棉铃虫六龄幼虫的相对 α-淀粉酶活性显着降低。GA3 处理的幼虫（800 μg g-1 饮食）中肠的组织学研究显示上皮细胞退化。丙氨酸和天冬氨酸转氨酶活性在最高浓度下降低。然而，与对照相比，酸性磷酸酶、碱性磷酸酶、γ-谷氨酰转移酶和乳酸脱氢酶活性显着增加。结果清楚地证明了 GA3 通过中断营养生理学和代谢对棉铃虫的不利影响。