The Protective Function of Ants Visiting the Extrafloral Nectaries of Bixa Orellana (Bixaceae)

This is the authors' abstract. We don't add key points for this paper.

Observations have been made on the nectar flow rates of the extrafloral nectaries on the pedicels of a number of individuals of the shrub Bixa orellana, growing in Costa Rica, and on the ant activities on the same plants. Damage to the flower buds by insects just prior to flower-opening can result in high abortion rates. Greatest nectar flow rates and ant activity were associated with this particularly vulnerable stage of development. More buds mature to ripe fruits on plants with higher visitation rates of ants at the extra-floral nectaries. The results suggest that the presence of numerous ants on a plant reduces the activities of phytophagous insects, and raises its relative reproductive fitness through increased production of fruits.