中文摘要：

【目的】昆虫自相残杀行为可以促进特定病原体的传播,这在利用昆虫病原体防治害虫方面有潜在的应用价值。本研究旨在探究棉铃虫Helicoverpa armigera幼虫自相残杀习性与其龄期及食物营养之间的相关性。【方法】分别饲喂室内品系和野外品系的棉铃虫幼虫含不同Na＋浓度的人工饲料,并在饲养至3龄、4龄、5龄和6龄时,将取食相同饲料的10头幼虫为一群组移入同一培养皿中,通过测定各处理幼虫存活率,评估幼虫龄期和饲料中的Na＋含量对自相残杀行为的影响。【结果】当以3龄和4龄为群组的起始龄期时,棉铃虫幼虫存活率显著低于起始龄期为5龄和6龄的群组。此外,取食正常人工饲料的幼虫存活率最高,取食缺钠饲料时,幼虫存活率明显下降。最后,幼虫群组起始龄期和食物Na＋含量对幼虫化蛹率无明显影响。【结论】结果说明,棉铃虫4和5龄幼虫与3和6龄幼虫相比,自相残杀行为发生的概率更大,而Na＋含量较低的食物在一定程度上促进自相残杀行为发生的可能性。本研究为在这一领域的进一步工作提供了基础。

英文摘要：

[ Aim ] Cannibalism could facilitate the infection of certain pathogens that can be transmitted by feeding on infected conspecifics. This may have potential applications in the control of pests by entomopathogens. Our study aims to explore the relation between cannibalism and age and nutrition in larvae of the cotton bollworm, Helicoverpa cannibalism of H. armigera larvae by feeding armigera. [ Methods ] We estimated the incidence of different concentrations of sodium to a laboratory population and a wild population, and examined whether dietary sodium had any effects on the cannibalism. [ Results ] The survival rates of the larvae of H. armigera were the lowest when the tests were initiated at the beginning carried out the beginning of the 3rd and 4th instars, statistically significantly increased when the experiments were the beginning of the 5th instar, and further raised when the experiments were performed at of the 6th instar. Moreover, the survival rates of the larvae fed on normal diet prior to experiment were the highest, and slightly but distinctly decreased when the larvae fed on sodium-deficient diet. In addition, the pupation rates of the larvae were similar, irrespective of whether the larvae fed on normal or sodium-deficient diets, and whether the experiments initiated at the beginning of the 3rd, 4th, 5th or 6th instar. [ Conclusion ] The results demonstrate that for H. armigera larvae cannibalism highly occurs in the 4th and 5th instars rather than the 3rd and 6th instars, and to some extent, sodium deficiency enhances cannibalism. This study provides a basis for further work in this field.