黄野螟群体大小对幼虫个体生存和发育的影响

幼虫聚集取食是一些鳞翅目昆虫提高幼虫生长和存活的手段。通过对聚集取食的黄野螟Heortia vitessoides Moore幼虫在室内条件下进行饲养，探究黄野螟幼虫的群体数量大小(分别为30、60、90头幼虫)对幼虫体长、发育速度、达末龄(5龄)时的存活率的影响。分析发现在排除天敌捕食和食物缺乏的前提下，从3龄开始，大群体(90头)的体长显著大于小群体(30头),大群体的幼虫发育速度显著快于小群体，大群体对幼虫前4个龄期时的成活率没有显著提高，尽管大群体的存活率在均值上高于小群体，但是幼虫总体存活率在不同群体中差异不显著。黄野螟幼虫的聚集取食对幼虫的生长的促进作用明显，显著促进了幼虫的生长，加快了幼虫的发育。

Effect of group size on the survival and growth of Heortia vitessoides Moore (Lepidoptera: Pyralidae)

Larval aggregation is a strategy employed by some lepidopteran insect to enhance the growth and survival of caterpillars. The study focused on effect of group size on the body length, developing speed and survival of Heortia vitessoides Moore. Caterpillars were reared under laboratory condition divided into 30, 60 and 90. The body length, developing speed and survival rate of caterpillars were measured. The body length of H. vitessoides larvae were significantly larger in larger group since 3rd instar. The developing speed was also significantly faster in larger groups. However, the survival rate was not significantly higher in larger group under laboratory conditions. The growth and developing speed were enhanced by caterpillar aggregation.