Population fluctuation of Scolytidae (Insecta: Coleoptera) in cocoa of Aragua State, Venezuela

Abstract

 The order Coleoptera includes species of the family Scolytidae as pests of forests in several regions of the world. The importance and density of this group are increasing in Venezuela mainly with species of ambrosia beetles, which feed on symbiotic fungi introduced and cultivated in their galleries. The objective of this research was to evaluate the occurrence and density of Scolytidae species damaging plants of cocoa in Cuyagua, Cumboto, Choroni and Chuao, State of Aragua, Venezuela. Ethanolic traps were used to study population fluctuation of Scolytidae species in plantations of cocoa. The Scolytidae species collected and identified of the tribe Xyleborini were Xyleborus ferrugineus Fabricius, X. affinis Eichhoff, X. spinulosus Blandford, X. vespatorius Schedl, X. volvulus (F.), Xylosandrus morigerus (Blandford), X. retusus (Eich.), Premnobius cavipennis Eichhoff, Sampsonius dampfi Schdl, Dryocoetoides nitidus Schedl y Xyleborinus sp., and of the tribe Cryphalini were Hypothenemus opacus (Eichhoff), H. erectus LeConte, H. sp. y Cryptocarenus sp. Likewise species that emerged from infected plants were collected X. ferrugineus (F), X. morigerus (Blanford), X. affinis, X. spinulosus Blandford, H. opacus (Eichhoff) and H. erectus LeConte. The last four species presented larger populations during periods of low rainfall while the first two presented other patterns. Population fluctuation was obtained for the six species that can be used in a program of Integrated Pest Management (IPM) in cocoa planting in Aragua State.