ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 70 Number 4
Fungi associated with pods of cocoa (Theobroma cacao L.)attacked by the borer Conotrachelus humeropictus Fiedler in Rondonia State, Brazil
Conotrachelus humeropictus Fiedler is the most important pest of cocoa (Theobroma cacao L.) and cupuassu (Theobroma grandiflorum Schum.) in north-western Brazil. The adults lay their eggs in young pods and the emerging larvae feed on the placenta, mucilage, and seeds. Adult larvae burrow out of the pods to pupate in the soil. During two years of investigations, tissues taken from the placenta or near galleries made by the borers were inoculated on potato dextrose agar and the isolated fungi were identified. The results show that the escape routes of the larvae facilitate the entry into the pods of fungi, bacteria and saprophytic nematodes. Altogether, 41 fungal species in 27 genera were identified. All the fungi were able to invade when inoculated into wounded detached green cocoa pods. Few were able to infect intact pods, showing that they are principally saprophytes or weak parasites.
Keywords: Contrachelus humeropitus; Theobroma cacao; Brazil