Problèmes entomologiques en replantation des palmeraies et des cocoteraies

Abstract

Given their complexity, natural ecosystems, such as primary forests, are highly stable. During the last ten years of its economic life span, which is approximately twenty-five years, an oil palm planting also becomes a complex environment, with hundreds of species made up, on the one hand, of insect pests and plants that have either developed naturally or have been introduced and, on the other hand, of their natural enemies. Felling an oil palm planting leads to sudden destruction of the complex system, which is replaced in young plantings by a highly simplified environment that is likely to be subject to frequent imbalances for many years, further exacerbated by often unavoidable human intervention. After felling, oil palm and coconut stems can provide an environment highly propitious to the development of major pests in young plantings, namely weevils of the genus Rhynchophorus, whose larval instars attack the plant's living tissues, and scarab beetles of the genera Oryctes, Strategus and Scapanes, whose adults attack developing tissues. Preventive measures exist to curb the development of these pests. If they fail, curative measures become necessary, including a trapping technique using pheromone substances isolated from the insects.