Interspecific pollen transfer between two coflowering species was minimized by bumblebee fidelity and differential pollen placement on the bumblebee body  

作　　者：Zhi-Huan Huang Huan-Le Liu Shuang-Quan Huang 

机构地区：[1]State Key Laboratory of Hybrid Rice,College of Life Sciences,Wuhan University,No.299 Bayi Road,Wuchang District,Wuhan 430072,China [2]School of Life Sciences,Central China Normal University,152 Luoyu Avenue,Hongshan District,Wuhan 430079,China

出　　处：《Journal of Plant Ecology》2015年第2期109-115,共7页植物生态学报（英文版）

基　　金：National Science Foundation of China(31030016,31270281)to SQ Huang.

摘　　要：Aims When sympatric flowering plant species in a natural community share pollinators,study of plant-plant interactions via interspecific pollen transfer(iPT)is essential for understanding species coexistence.However,little is known about the extent of iPT between interactive species and its causes.Methods To explore how sympatric flowering plants sharing pollinators mini-mize deleterious effects of iPT,we investigated the pollination ecol-ogy of two endemic species,Salvia przewalskii and Delphinium yuanum,in an alpine meadow in the Hengduan mountains,southwest China.We quantified conspecific and interspecific visits by shared bumblebee pollinators,amounts of pollen placed on different body sites of the pollinators and stigmatic pollen loads on open-pollinated flowers.To examine whether iPT affects female fitness,we measured pollen germination and seed production in the two species in an artificial pollination experiment.Important Findingsone bumblebee species,Bombus trifasciatus,was found to be the sole effective pollinator for the two coflowering species.Pollination experiments indicated that deposition of heterospecific pollen could significantly decrease seed set in both species.Experiments showed that S.przewalskii pollen could germinate well on stigmas of D.yuanum,inhibiting conspecific pollen germination in D.yuanum.However,seed set was not lower under open pollination than under cross-pollination within species,suggesting that no female fitness loss was caused by iPT.in foraging bouts with pollinator switches,switches from S.przewalskii to D.yuanum were relatively more fre-quent(8.27%)than the converse(1.72%).However,iPT from S.prze-walskii to D.yuanum accounted for only 1.82%of total stigmatic pollen loads while the reverse iPT to S.przewalskii was 8.70%,indi-cating that more switches of bumblebees to D.yuanum did not result in higher iPT.by contrast,selection for reduced iPT to S.przewalskii would limit pollinator switches from D.yuanum.We found that a bumblebee generally carried pollen grains from both

关 键 词：pollination competition interspecific pollen transfer pollinator fidelity pollen placement BUMBLEBEES pollen germination female reproductive success Salvia przewalskii Delphinium yuanum 

分 类 号：Q94[生物学—植物学]