Pollen transfer, and hence sharing of pollinators, among Primula veris, Narcissus assoanus, and Potentilla tabemaemontani in Northern Spain is demonstrated in the study of pollen loads on their stigmas. The length of style in both P. veris and N. assoanus is dimorphic (the former being a typical distylous species); they resemble each other in flower morphology (narrow-tubed), color, and nectar characteristics. Therefore, interspecific pollen transfer between these two species shows a pattern related to these similarities. It is inferred that the pattern of interspecific pollen transfer is mediated mainly by long-tongued pollinators seeking nectar, and that of intraspecific pollen transfer by long- and short-tongued pollinators feeding on nectar and pollen, respectively. The floral features of P. tabemaemontani are markedly different, especially in flower architecture (open) and reward (pollen). Accordingly, pollen transfer to other species is reduced, the long-styled flowers of N. assoanus being the exception. This is probably due to frequent visits of pollencollecting insects to the upper stamen whorl of N. assoanus, which therefore would also be a pollen-rewarding species, as has been observed in other similar Narcissus species.
Bibliographical noteFunding Information:
The staff of the Instituto Pirenaico de Ecologia (IPE-CSIC, Jaca, Spain) provided facilities for field and laboratory work. We are especially grateful to Luis Villar and Begofla Garcia for their help in the field. Two anonymous reviewers provided useful comments. The final part of the elaboration of this paper was supported by a DGICYT grant (no. PB91~894) to JA.
ASJC Scopus subject areas
- Agricultural and Biological Sciences (all)