Ecological Research

, Volume 17, Issue 3, pp 283–294

Diverse visitors with various pollinator importance and temporal change in the important pollinators of Geranium thunbergii (Geraniaceae)

Authors

    • Laboratory of Entomology, Faculty of AgricultureKinki University
Original Article

DOI: 10.1046/j.1440-1703.2002.00488.x

Cite this article as:
Kandori, I. Ecol Res (2002) 17: 283. doi:10.1046/j.1440-1703.2002.00488.x

Assessing pollinator importance of each floral visitor to a plant species is a key to understanding plant–pollinator interaction. The present study examined visitation frequency, pollination efficiency, and pollinator importance of the full range of floral visitors to Geranium thunbergii natural population, by measuring seed-set. During 2 years of observations, the flowers were visited by at least 45 insect species belonging to four orders. Among the main 22 visitor species, 11 species belonging to three orders (Hymenoptera, Diptera, and Lepidoptera) acted as the efficient pollinators. In both years, Hymenoptera, especially bees, was the most important pollinator to G. thunbergii. Thus, the flowers could be considered as bee-pollinated. However, the most important species were not constant between years. The study also documented that the efficient pollinators have larger body sizes. The dish-shaped floral morphology, taxonomically diverse pollinators, and temporal change in the most important pollinators indicate that G. thunbergii–pollinator interaction is a rather generalized system. The results suggest that casual observations of visitation, or even precise measurement of pollinator importance in a single season is insufficient to identify important pollinators.

Key words

generalized systempollination efficiencyseed-setvisit durationvisitation frequency.

Copyright information

© Ecological Society of Japan 2002