Preferences, patterns and consequences of branch removal on the dioecious tropical tree Spondias purpurea (Anacardiaceae) by the insect borer Oncideres albomarginata chamela (Cerambycidae)

Most studies of plant-herbivore interactions in dioecious species have evaluated foliar herbivory. In this studie we evaluated preferences of branch removal by the insect borer Oncideres albomarginata chamela in the tropical dioecious tree Spondias purpurea L. The objectives were to determine the preferences and patterns of the removal of branches, to evaluate the effect of branch removal in the vegetative regeneration of branches, and to evaluate the effect of branch removal on the regeneration of fertile branches of male and female trees of S. purpurea. During three consecutive years of study, damage caused to branches by the girdled borer was associated with plant gender. The proportion of branches removed by the insect was greater for female than for male trees. The effects of branch removal were evaluated in attacked regenerated and unattacked branches. Removed branches regenerated a year after the insect borer attacked them. Branch removal affected the probability of producing fertile branches. The preference by O. a. chamela is apparently associated with the nutritional quality of the host.