Pollination biology in an endangered rocky mountain toadflax (Linaria cavanillesii)

Abstract

Knowledge about the reproductive system of species inhabiting rocky habitats is scarce. The reproductive biology (floral biology, experimental pollination, insect visits, inbreeding depression, and seed predation) of the rupicolous Linaria cavanillesii was analyzed under field and experimental conditions. Self-compatibility was revealed by the high fruit set, seed set, and seed mass in the pollination experiment. Furthermore, results disclose that this species does not need insect visitors for seed production since fruit set after autonomous self-pollination was similar to that by hand cross-pollination. Self-offsprings were not affected by a strong degree of inbreeding depression in early life-cycle stages. Seed predation by Cucurlionidae is the main limiting factor of fruit and seed production in this species. Contrary to other perennial species of Linaria previously studied, L. cavanillesii represents the first clear report of self-fertility.

Keywords:

• Conservation
• Linaria
• reproductive biology
• seed predation
• selfing

Acknowledgements

The authors wish to thank E. Barona for field assistance and F. Barraclough and John O'Brien for reviewing the English version. This research was supported by the Spanish General Direction of Scientific and Technical Research (DGICYT) through the Project REN2002-02434/GLO.