美丽枕果榕的人工授粉实验

Artificial Pollination in Ficus drupacea var. glabrata

以美丽枕果榕Ficusdrupaceavar glabrata为材料,研究了在传粉完全中断的条件下,采用树内和树间的人工授粉以恢复传粉获得种子。实验结果表明,雌花被同株的雄花授粉不育,被异株的雄花授粉可育,且长花柱雌花、短花柱雌花及中间类型雌花均可经授粉后发育为正常的种子,种子的平均发芽率为76 34%,说明人工授粉是恢复此种榕树传粉的有效手段。

Fig trees (Ficus spp.; Moraceae) are pollinated by species-specific fig wasps (Agaoninae) and have long been held as the example system of coevolution. In fig trees' distributing marginal regions or not in their natal habitat, extinctions of potential pollinators have occurred in a kind of ornamental fig tree, Ficus drupacea var. glabrata, in Guangzhou. According to our observations, no fig wasp was found to enter the receptive syconium of this fig tree to pollinate and reproduce, showing that the mutualism has been disrupted. Laboratory study revealed that pollination and seed dispersal biological traits of the fig tree were still normal in Guangzhou. Habitat loss, pollinators extinction and the small population sizes in Guangzhou, appears to be the main problem facing this species. Artificial pollination experiment is conducted to overcome the pollination breakdown, showing that infertility occurs when pollination conducted intra-tree and fertility occurs when pollination conducted between trees. All types of female flowers (long-styled, short-styled and medium-styled) can develop into seeds after pollinated in female phase. The seed germination rate is about 76.34 %. The artificial pollination is an effective method to protect this species.