Effects of flower number on estimated pollen transfer in natural populations of three hermaphroditic species: an experiment with fluorescent dye

Autor: T. J. De Jong, M. C. J. Rademaker
Rok vydání: 1998
Předmět:
Zdroj: Journal of Evolutionary Biology. 11:623-641
ISSN: 1420-9101
1010-061X
DOI: 10.1046/j.1420-9101.1998.11050623.x
Popis: The relationship between the number of open flowers and pollen transfer to stigmas was estimated in three insect-pollinated species (Cynoglossum officinule, Echium v~&ure and Oenothrru crythrocrpulu) in 1995 and 1996, using fluorescent dye as a pollen analogue. Dye was applied to an equal number of flowers on a small, a medium and a large individual and its pattern of dispersal to stigmas of conspecifics in local populations was observed. In Cynoglossunz oj~cinde and in Echium vulgarr large individuals tended to receive more visits per flower. In Oenothera erythrowpulu no difference in number of visits per flower was found between small and large individuals. Geitonogamous pollination clearly occurred in all species. In C~nog/ossum o&inale large individuals transferred more pollen per flower within the same plant (geitonogamy) and an equal or a slightly smaller amount between plants, compared to small individuals. As a result total pollen transfer per flower increased in both years with increasing flower number. In Echium culgure and in Omothrra rrythrocrpah large individuals transferred more pollen per flower within the plant (pollen discounting), but a significantly lower amount per flower to other individuals in the populations compared to small individuals. For both these species, there is no difference in total pollen transfer between small and large individuals. In general, the male fitness curve, as estimated by pollen transfer, is a decelerating function of flower number. We discuss this in relation to optimal sex-allocation and the pollen donation hypothesis.
Databáze: OpenAIRE
Externí odkaz: