Population fluctuation and infestation levels of the cupuaçu fruit borer

Abstract

The most important pest of the cupuaçu crop is the fruit borer, Conotrachelus humeropictus Fiedler (Coleoptera: Curculionidae), wich severely damages fruits and is disseminated all over North Brazil. The objectives of this study were evaluating the population fluctuations of C. humeropictus adults, infestation levels and to characterize the pest larval attack in cupuaçu fruits of agroforestry systems of the Rondonia State, Brazil. Population fluctuations from C. humeropictus adults were evaluated weekly from March/98 to July/00 in twenty cupuaçu plants, by shaking the tree branches, of two producer areas. During two harvest periods, fruits attacked by the borer were collected and examined for evaluation of larvae population. Pest infestation was determined by the percentage of damaged fruits. C. humeropictus adults occur year around on cupuaçu plants, but predominate at the stages of flowering, fruit formation and during the harvest period. It was observed that mature and non-mature fruits are attacked by the pest; larvae of different ages can occur in a same fruit; the insect may cause losses greater than 50% of fruit yield.