HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

What's this?

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cayenne Engel, E. Articles by Irwin, R. E. Search for Related Content PubMed Articles by Cayenne Engel, E. Articles by Irwin, R. E. Agricola Articles by Cayenne Engel, E. Articles by Irwin, R. E. Social Bookmarking                            What's this?

Linking pollinator visitation rate and pollen receipt¹

²Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA; ³Department of Biology, Agnes Scott College, Decatur, Georgia 30030 USA; ⁴Institute of Ecology, University of Georgia, Athens, Georgia 30602 USA

The majority of flowering plants require animals for pollination, a critical ecosystem service in natural and agricultural systems. However, quantifying useful estimates of pollinator visitation rates can be nearly impossible when pollinator visitation is infrequent. We examined the utility of an indirect measure of pollinator visitation, namely pollen receipt by flowers, using the hummingbird-pollinated plant, Ipomopsis aggregata (Polemoniaceae). Our a priori hypothesis was that increased pollinator visitation should result in increased pollen receipt by stigmas. However, the relationship between pollinator visitation rate and pollen receipt may be misleading if pollen receipt is a function of both the number of pollinator visits and variation in pollinator efficiency at depositing pollen, especially in the context of variable floral morphology. Therefore, we measured floral and plant characters known to be important to pollinator visitation and/or pollen receipt in I. aggregata (corolla length and width and plant height) and used path analysis to dissect and compare the effect of pollinator visitation rate vs. pollinator efficiency on pollen receipt. Of the characters we measured, pollinator visitation rate (number of times plants were visited multiplied by the mean percentage of flowers probed per visit) had the strongest direct positive effect on pollen receipt, explaining 36% of the variation in pollen receipt. Plant height had a direct positive effect on pollinator visitation rate and an indirect positive effect on pollen receipt. Despite the supposition that floral characters would directly affect pollen receipt as a result of changes in pollinator efficiency, corolla length and width only weakly affected pollen receipt. These results suggest a direct positive link between pollinator visitation rate and pollen receipt across naturally varying floral morphology in I. aggregata. Understanding the relationship between pollinator visitation rate and pollen receipt may be of critical importance in systems where pollinator visitation is difficult to quantify.

Key Words: floral morphology • hummingbird pollination • Ipomopsis aggregata • path analysis • Polemoniaceae • pollen receipt • pollinator efficiency • pollinator visitation

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				A. O. Brown and J. N. McNeil Pollination ecology of the high latitude, dioecious cloudberry (Rubus chamaemorus; Rosaceae) Am. J. Botany, June 1, 2009; 96(6): 1096 - 1107. [Abstract] [Full Text] [PDF]

				M. Burd, T.-L. Ashman, D. R. Campbell, M. R. Dudash, M. O. Johnston, T. M. Knight, S. J. Mazer, R. J. Mitchell, J. A. Steets, and J. C. Vamosi Ovule number per flower in a world of unpredictable pollination Am. J. Botany, June 1, 2009; 96(6): 1159 - 1167. [Abstract] [Full Text] [PDF]

				S. E. Elliott and R. E. Irwin Effects of flowering plant density on pollinator visitation, pollen receipt, and seed production in Delphinium barbeyi (Ranunculaceae) Am. J. Botany, May 1, 2009; 96(5): 912 - 919. [Abstract] [Full Text] [PDF]

				H. F. Sahli, J. K. Conner, F. H. Shaw, S. Howe, and A. Lale Adaptive Differentiation of Quantitative Traits in the Globally Distributed Weed, Wild Radish (Raphanus raphanistrum) Genetics, October 1, 2008; 180(2): 945 - 955. [Abstract] [Full Text] [PDF]

				C. Alonso Pollination success across an elevation and sex ratio gradient in gynodioecious Daphne laureola Am. J. Botany, August 1, 2005; 92(8): 1264 - 1269. [Abstract] [Full Text] [PDF]