Leaf herbivory modulates fruit trait correlations within individual plants

Abstract

Plant performance is based on the relationship between resource acquisition and allocation to complete essential functions. Herbivory causes compromises in resource allocation that impact at the plant and within-plant (sub-individual) levels. This impacts fruit display traits which in turn affect reproductive success and seed dispersal. Because leaf damage affects resource allocation, herbivory should modulate the relationship between fruit display traits. We explore the relation between the level of leaf herbivory (mean damage and coefficient of variation) and fruit display traits in Vassobia breviflora (Solanaceae). According to trait function, we explore relationships between reproductive traits (seed number and weight), reward traits (sugar concentration, pulp weight), and relationships between reproductive and reward traits. We found no effect of herbivory on the correlation between reproductive traits, but an effect was found on the correlation between rewards traits. In conclusion, herbivory affects the correlation between fruit traits, and the magnitude and direction of the association between traits vary according to the magnitude and variation of the damage at the within-plant level. In evolutionary terms, our results suggest that within-plant variation in leaf traits would constitute a strategy to resolve allocation conflicts derived from damage and to maintain fruit display characteristics that favor the interaction with seed dispersers.