本地种西番莲与外引种西番莲的花外蜜腺-蚂蚁-植食昆虫相互作用系统的比较

外引植物如何和当地生物建立相互关系是入侵生物学和进化生物学关注的关键科学问题.本实验以西双版纳当地自然分布的长叶西番莲(Passiflora siamica)和近年从南美新引种的红花两番莲(P.coccinea)为材料,探讨两种西番莲植物-蚂蚁-植食昆虫间相互关系系统对变化响应的差异.结果表明,共有24种蚂蚁取食花外蜜液,利用两种西番莲的蚂蚁数量没有显著差异(t=1.30,P=0.20),但在种类组成上存在显著差异(χ~2=14.76,df=4,P<0.01).植食昆虫多为蜗牛、螽斯、鳞翅目幼虫等广适性昆虫.去除蚂蚁处理均未对两种西番莲植物的平均叶面积损失造成显著影响.该研究表明两种两番莲的花外蜜腺-蚂蚁-广适性昆虫的相互作用系统对变化的响应没有显著差异,而与专食性昆虫相互作用系统对变化的响应的差异则有待进一步研究.

Comparison of the Differences in Response to the Change of the Extrafloral Nectar-ant-herbivore Interaction System Between a Native and an Introduced Passiflora Species

How introduced plants associate with native bioticis one of the fundamental quesfions in evolutionary biology and invasive biology.Extrafloral nectar (EFN) bearing plants usually use nectar to attract ants while those ants could help pla-nts defense herbivores;establishing a plant-ant-herbivore interactive system.In this study,we conducted artificial ant-ex-clusion,EFN-exclusion,herbivore exclusion,ant and herbivore exclusion to compare the differences in response to the change of the extrafloral neclar-ant-herbivore interaction system in an native passionflower(Passiflora siamica) and an ne-wly introduced species(P.coccinea).A total of about 24 ant species were recorded consuming the EFN resource.There was no significant difference in the total number of visiting ants while ant species composition was different in the two Passi-flora plants(χ~2=14.76,df=4,P<0.01).The most abundant ant species for P.siamica was Dolichoderus thoracicus while for P.coccinea was Paratrechina sp.The herbivorous insects observed were mainly generalists,including snails,ka-tydisds(Pseudophyllidae) or some larvae of butterflies and moths.The amount of nectar per leaf produced from P.siamica is significantly hisherthan P.coccinea(Willcox,z=-3.87,P<0.01).Ant-exclusion in this experiment did not signifi-cantly influence the average leaf loss per plant.The treatments for ant-exclusion,herbivore exclusion,and ant+herbivore exclusion all did not significantly influence the EFN production.As a whole,the plant-ant-generalist herbivore in the two Passiflora species did not show a significant difference in the response to the change, while the interactive system with specialist herbivores request further investigation.