桔小实蝇与番石榴实蝇幼虫的种间竞争研究

Studies of interspecific competition between Bactrocera dorsalis (Hendel) and Bactrocera correcta (Bezzi) in larvae stage

本文研究了桔小实蝇Bactrocera dorsalis(Hendel)与番石榴实蝇Bactrocera correcta(Bezzi)幼虫在实验室2种环境温度,4种寄主及5个虫口数量比例条件下的种间竞争现象。结果显示,在温度26℃以桃和香蕉为寄主条件下,桔小实蝇存活率高于番石榴实蝇;以芒果为寄主情况下两者存活率差异不显著;以番石榴作为寄主,虫口数量较大的一方具有竞争优势。在温度33℃条件下,就所测试的各种寄主,番石榴实蝇均具有竞争优势。分析发现,温度是影响番石榴实蝇幼虫存活率的关键环境因素;虫口比例对于桔小实蝇的存活率有重要影响;在不同的寄主中,桔小实蝇与番石榴实蝇的存活率也表现出较大的变化,寄主种类与温度及虫量形成综合效应,决定了桔小实蝇与番石榴实蝇竞争的最终结局。

This paper deals with the interspecific competition between Bactrocera dorsalis and B. correcta in larvae stage. We selected 2 environmental temperatures, 4 host species and 5 population proportional levels in this study. The results showed that, under the condition of 26 ℃, with peach and banana as the host, the survival rate of B. dorsalis was higher than B. correcta. Under the same temperature conditions, when use the mango as host, there was no significant difference in survival rate between this two species. When use the guava as host, the species with higher individual number got competitive advantage. Under the condition of 33℃, B. correcta got competitive advantage in all 4 hosts. The analysis results showed that temperature was the key factors for guava fruit fly survival; the individual number has important influence on interspecific competition result for B. dorsalis. Host species may have synergistic effects with temperature and population proportion and play vital roles in competition of the two fruit flies.