两种斑潜蝇及其寄生蜂空间生态位的研究

三叶斑潜蝇和美洲斑潜蝇是广东地区发生和危害比较严重的两种蔬菜潜叶蝇,通过对两种斑潜蝇及其寄生蜂空间生态位的调查研究表明,发现两种斑潜蝇的生态位宽度受寄主影响各有不同,与其寄生蜂的生态位重叠值较小。底比斯釉姬小蜂Chysocharis pentheus(Walker)、冈崎灿姬小蜂Chysonotomyia okazakii(Kamijo)和丽灿姬小蜂Chysonotomyia formosa(Westwood)生态位宽度值相近且均高于其它寄生蜂,分布较其它三种寄生蜂广,三种寄生蜂对斑潜蝇的寄生跟随作用较强;甘蓝潜蝇茧蜂Opius dimidiatus(Ashmead)、黄潜蝇釉姬小蜂Chysocharis oscinidis Ashmead和异角亨姬小蜂Hemiptarenus varicornis(Girault)的时间生态位宽度值(B’i)均小于0.1,在大田中发生的跨度范围很窄,具有季节集中性。三叶斑潜蝇和美洲斑潜蝇的种间竞争,表现在对寄主资源的占有和掠夺上具有一定的竞争性,这也是田间三叶斑潜蝇种群数量一直高于美洲斑潜蝇的主要原因之一。

Research on spatial niche between two vegetable leafminers and their parasitoids

Liriomyza trifolii and Liriomyza sativae were two very important vegetable leafminers in the field.According to the research on the spatial niche between the two leafminers and their parasitoids,the results showed that the value of niche overlap of two leafminers and their enemies were less than 0.5,and the niche overlapped was very less.The niche breadths of the two leafminers varied with the hosts species.The niche breadths of thee parasitoids: C.pentheus(Walker),C.okazakii(Kamijo) and C.formosa(Westwood) were close but higher than the other parasitoids,and the following and parasiting effects were stronger.On the other hand,the niche breadths of C.oscinidis,H.varicornis and O.dimidiatus were less than 0.1,which distribution range were narrow and the happening trend was seanonal centrality.The competition index between L.trifolii and L.sativae was 0.6076,which showed that these two leafminers had the ability to occupy and rab the same resources.