【作者】 杨培； 李宗波； 彭艳琼； 杨大荣；

【Author】 YANG Pei~(1,2),LI Zong-bo~(1,2),PENG Yan-qiong~1,YANG Da-rong~(1,*) (1.Xishuangbanna Tropical Botanical Garden,the Chinese Academy Sciences,Kunming Yunnan 666303,China; 2 Graduate School of the Chinese Academy Sciences,Beijing 100049)

【机构】 中国科学院西双版纳热带植物园； 中国科学院研究生院；

【摘要】 在榕蜂共生体系中,互惠双方都是利用榕果内有限的雌花资源繁殖后代。对于雌雄异株榕树,雄树为榕小蜂提供繁衍后代的场所,雌树则只形成种子。它们是如何解决这种繁殖利益冲突的?作者于2007-2009年在西双版纳地区通过对两种雌雄异株榕树Ficus auriculata和Ficus sp.的花柱和其传粉榕小蜂产卵器进行观察和测量,对榕果进行单果人工控制放蜂等试验,放蜂为两个处理:寄主榕树单果单蜂和非寄主交叉单果单蜂。结果发现,榕小蜂产卵器长于雄果内雌花花柱,而短于雌果内雌花花柱,前者花柱短粗直,独立生长,柱头为喇叭状开口;后者则长细弯,柱头相互联合在一起,形成联合花柱。放蜂结果显示,雄果能繁育榕小蜂后代并有少量种子产生,雌果只产生种子。这说明榕果内的雌花命运主要取决于花柱长度,并且只有当榕小蜂产卵器比花柱长出某一阈值时才能正常繁殖后代。此外,对于雌果中小花的命运,花柱形态结构起到了重要作用。试验同时还揭示了榕小蜂与其寄主在长期的协同进化过程中,在结构上已经高度协调统一,并且就这两种榕树而言,可能会在传粉者大量减少的情况下向雌雄同株转化。更多还原

【Abstract】 In fig-wasp mutualism,Fig trees(Ficus) and their fig pollinating wasps(Agaonidea) both use the limited florets source to reproduce.In dioecious Ficus species,gall figs only produce offspring of wasps and seed figs produce seeds no wasps.How do they deal with the conflict? The style length of Ficus auriculata and Ficus sp. and ovipositor length of their pollinators were observed and measured.One foundation was manually introduced into each syconium.Our studies showed that ovipositor length was longer than style length of gall figs and shorter than it in seed figs.Moreover,the styles in gall figs were short and straight,and the each stigma looked like bugle, but the styles in seed figs were very different,which were narrow and curly,and the stigmas were cohesive.The results also indicated that there were offspring of pollinators and few of seeds in gall figs,but in seed figs just seeds and no pollinators.It implied that the fate of florets mainly depends on style length,and if pollinators reproduced successfully,the ovipositor length must be longer threshold than style length,furthermore,the florets’ structures also paid a important rule in the fate of florets in seed figs.Fig pollinating wasps evolved according to evolution of their host fig trees,and their reproductive structures highly correspond with their host trees.If their pollinators were greatly reduced,the tow dioecious species might transform to monoecious species.更多还原