生物多样性 ›› 2008, Vol. 16 ›› Issue (6): 525-532.DOI: 10.3724/SP.J.1003.2008.08216

• 论文 •    下一篇

榕小蜂食性分化与榕树―榕小蜂系统稳定性

孙宝发1,2, 王瑞武1*, 胡忠2   

  1. 1 (中国科学院昆明动物研究所, 昆明 650223)
    2 (汕头大学生物系, 汕头 515063)
  • 出版日期:2008-11-20 发布日期:2008-11-20
  • 通讯作者: 孙宝发

Diet segregation of fig wasps and the stability of fig–fig wasp mutualism

Baofa Sun 1,2, Ruiwu Wang1* , Zhong Hu2   

  1. 1 Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223
    2 Biology Department, Shantou University, Shantou 515063
  • Online:2008-11-20 Published:2008-11-20
  • Contact: Baofa Sun

摘要: 在榕树与其传粉小蜂组成的互利共生系统中, 理解传粉小蜂与各种非传粉小蜂如何共存是解决这一系统稳定性维持机制问题的关键之一。生态位分化被普遍认为是传粉小蜂与各种非传粉小蜂共存的最主要动力。而作为生态位分化中最基础的食性分化在这一系统中如何具体实现尚不清楚。2006年12月至2007年6月, 我们以聚果榕(Ficus racemosa)为材料, 通过对果内6种榕小蜂进行独立放蜂及两两组合定量放蜂, 并对传粉小蜂分别进行不携带花粉和不能产卵的技术处理, 研究了寄生在聚果榕果内的5种非传粉小蜂的食性及相互关系, 分析了在不同季节下寄生蜂与寄主间的相关系数。研究结果表明: 在5种非传粉小蜂中, Platyneura testaceaP. mayri是造瘿者, 能独立刺激子房发育成瘿花, 并使果实发育成熟; 而Apocrypta sp.、A. westwoodiP. agraensis只能寄生于某些已发育的虫瘿, 为拟寄生者, 它们各自分别与P. testacea、P. mayri和传粉小蜂Ceratosolen fusciceps存在着一对一的寄生关系。拟寄生者与寄主间的相关性在不同季节下会显示出不同的结果, 这表明过去文献中用物种间的相关系数推理而确定的食性关系可能是不可靠的。对自然采集榕果内的小蜂群落分析表明, 传粉小蜂处于优势地位, 这说明在自然情况下非传粉小蜂的种群维持在一个较低水平, 对榕树—传粉小蜂系统稳定性影响较小, 故能与之长期共存。

关键词: Cycas revoluta, nrDNA ITS, 致同进化, 假基因, 多态性

Abstract: In the fig–fig wasp reciprocal mutualism, understanding mechanisms of coexistence between pollinating wasps and non-pollinating wasps is an important and relevant topic. Niche partitioning has widely been considered as the most important mechanism in the coexistence of pollinating and non-pollinating wasps. In this study, we experimentally examined the diet of five species of non-pollinators and the relationship among fig wasps in Ficus racemosa in Xishuangbanna, southern China, from Dec. 2006 to Jun. 2007. Platyneura testacea and P. mayri are gall-makers, but oviposit sequentially, utilizing different female flowers at different developmental stages; Apocrypta sp., A. westwoodi and P. agraensis are parasitoids of P. testacea, P. mayri and Ceratosolen fusciceps respectively, presenting species-specific relationships with the hosted species. Species correlation coefficients differed greatly among seasons and conditions, suggesting that the use of correlation analysis to deduce or identify relationships between species in previous studies may be of limited value. Pollinators were the dominant species at our study sites. In these conditions, non-pollinating wasps exist at relatively low population density, and therefore may have a weak impact on the stability of the mutualism, potentially enabling the non-pollinating wasps coexist with the mutualism between figs and fig wasps.

Key words: Cycas revoluta, nrDNA ITS, concerted evolution, pseudogenes, polymorphism