首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Pollination effectiveness and pollinator importance in a population of Heterotheca subaxillaris (Asteraceae)
Authors:Kenneth M Olsen
Institution:(1) Department of Biology, Box 1137, Washington University, 1 Brookings Drive, St. Louis, MO 63130-4899, USA fax: (314) 935-4432, US
Abstract: Assessing the relative contributions to seed set for each of a plant species’ floral visitors provides an indication of the relative influence of these visitors on the plant’s reproductive success. This study examined pollinator activity and seed set in a population of Heterotheca subaxillaris, a species that exhibits a floret dimorphism (heads bearing disk and ray florets), and that is visited by both generalist foragers and specialist bees. Visits by nine bee genera and one genus of skipper were recorded in the study population. During the period of study, these insects varied in their relative abundance, in their foraging activity on a head, and in their pollination effectiveness. The pattern of pollination effectiveness shown by the different pollinators was similar for both floret types, although seed set was higher overall for ray florets. Pollinator importance, calculated as the product of pollination effectiveness and relative abundance, was dictated by a pollinator’s relative abundance. The single specialist bee species observed in the study population proved to have neither higher pollination effectiveness nor higher pollinator abundance than other pollinators. This would suggest that H. subaxillaris is not under strong selective pressure to co-specialize with its specialist visitor. Received: 21 December 1995 / Accepted: 20 June 1996
Keywords:  Pollination effectiveness  Pollinator importance  Floret dimorphism  Pollinator specialization  Heterotheca subaxillaris
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号