Use of biological control in tropical tree crops : CIRAD research results

Research undertaken by CIRAD entomologists, specialized in tree crops, has concentrated on palms, oil palm and coconut, coffee, cocoa, fruit trees and forest species. Much of the research was intended to improve knowledge of abiotic and biotic factors that limit pest population, particularly entomophagous insects (parasitoids and predators) and entomopathogenic organisms (fungi and viruses), olfactory trapping techniques using chemical mediators (pheromones and allelochemical compounds), and visual trapping technqiues. All these investigations have made it possible to opt for partiuclar entomophagous organisms, or develop a biological control method using an entomopathogen or a pheromone substance. Several parasitoids and predators introductions have been successful and in some cases it has been possible to introduce cultural techniques unfavourable to certain pests. Lastly, the use of tolerant material can be recommended in a few cases. Wherever it has not been possible to propose a biological control method, research has at least provided advice to users regarding rational chemical control methods that are more invironment-friendly. (Résumé d'auteur