Ants, Extrafloral Nectaries and Herbivory on the Passion Vine, Passiflora incarnata

Abstract

A temperate species, Passiflora incarnata, of the predominately tropical family Passifloraceae, possesses two sets of extrafloral nectaries which are visited by five species of ants. In an old field, plants with the extrafloral nectaries removed attracted fewer ants, experienced greater herbivory and produced fewer fruits than plants with extrafloral nectaries intact. The number of ants per plant was positively correlated with the number of extrafloral nectaries and negatively correlated with the percent herbivory.