contribution of pollinators to seed production as revealed by differential pollinator exclusion in clerodendrum trichotomum (lamiaceae)传粉者的贡献作为揭示了微分授粉种子生产排除在clerodendrum trichotomum(唇形科).pdfVIP

Contribution of Pollinators to Seed Production as Revealed by Differential Pollinator Exclusion in Clerodendrum trichotomum (Lamiaceae) 1 1 2 Ryota L. Sakamoto *, Motomi Ito , Nobumitsu Kawakubo 1 Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan, 2 Graduate School of Applied Biological Sciences, Gifu University, Gifu, Japan Abstract A diverse assemblage of pollinators, such as bees, beetles, flies, and butterflies, will often visit a single plant species. However, evaluating the effect of several insects on fruit and seed production is difficult in plants visited by a variety of insects. Here, we analyzed the effect of three types of pollinators, Papilio spp., Macroglossum pyrrhosticta, and Xylocopa appendiculata on fruit and seed production in Clerodendrum trichotomum by using a flower visitor barrier experiment with nets of specific mesh sizes. As a result, fruit/flower and seed/ovule ratios were significantly lower under Papilio exclusion than under natural conditions. On the other hand, ratios were not significantly different between Papilio excluded and both Papilio and M. pyrrhosticta excluded treatments. Therefore, Papilio and X. appendiculata are effective pollinators, whereas M. pyrrhosticta, which was the most frequent visitor, of C. trichotomum, is not. From our observations of visiting behaviors, we believe that because M. pyrrhosticta probably promotes self- pollination, this species is a non-effective pollinator. This is the first study to separate and compare the contribution of various visitors to the reproductive success of a plant. Citation: Sakamoto RL, Ito M, Kawakubo N (2012) Contribution of Pollinators to Seed Production as Revealed by Differential Pollinator Exclusion in Clerodendrum trichotomum