No evident sex-biased herbivory but phenological and interannual variation in Fuchsia parviflora (Onagraceae) a dioecious Neotropical shrub

Abstract

Herbivory may have a great impact in plants, reducing plant biomass and fitness. Herbivory patterns may differ among genders in dioecious species, affecting male and female plants differentially, which has been suggested to be a consequence of differences in resource allocation among genders. In this study, we evaluated herbivory intensity and mechanical defenses among genders during two years and during different phenological stages in populations of Fuchsia parviflora, a dioecious shrub. We also evaluated generalist and specialist herbivore gender preferences through a cafeteria experiment. No evident herbivory patterns were detected among genders using both the proportion of leaves damaged and the proportion of leaf area removed, except during one year in two populations where females had a significantly higher proportion of leaves damaged. This patter is similar to the specialist herbivore preference detected in the cafeteria experiment. We also found significant differences in herbivory intensity among phenological stages, populations and years, highlighting the relevance of continuous sampling to have a general picture of herbivory patterns in dioecious plants.