A review of the issues and management of the red palm weevil Rhynchophorus ferrugineus (Coleoptera: Rhynchophoridae) in coconut and date palm during the last one hundred years
The red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) a concealed tissue borer, is a lethal pest of palms and is reported to attack 17 palm species worldwide. Although the weevil was first reported on coconut Cocos nucifera from South Asia, during the last two decades it has gained a foothold on date palm Phoenix dactylifera in several Middle Eastern countries from where it has moved to Africa and Europe, mainly due to the movement of infested planting material. In the Mediterranean region, RPW also severely damages Phoenix canariensis. Currently, the pest is reported in c. 15% of the coconut growing countries and in nearly 50% of the date palm growing countries. Infested palms, if not detected early and treated, often die. However, palms in the early stages of attack respond to chemical treatment with insecticide. RPW has been managed in several countries employing an integrated pest management (IPM) strategy including the use of food baited pheromone traps. Early detection of infestation in the field is important for the success of any RPW IPM programme. Ideally, movement of planting material from infested plantations within the country and also From one country to another needs to be stopped. Wherever this is not possible, it is essential to implement strict pre and post entry quarantine regimes, wherein only pest free and certified planting material can be transported. The existing pheromone based IPM programme can be strengthened by intensifying the search for effective natural enemies, coupled with the introduction of resistance in palms to RPW. This article reviews the work done during the last 100 years on various aspects of RPW viz. life history, damage and symptoms of attack, seasonal activity, spatial distribution, host range, IPM and its main components, including trapping adult weevils and chemical control, besides biological control, host plant resistance and male sterile technique.ResumeLe charancon rouge du palmier (RPW) Rhynchophorus ferrugineus (Olivier) un foreur des troncs, est un ravageur mortel des palmiers, signale sur 17 especes de palmiers a travers le monde. Bien que signale pour la premiere fois sur le cocotier Cocos nucifera en Asie du Sud, au cours des deux dernieres decades, il s'est etabli sur le palmier dattier Phoenix dactylifera dans plusieurs pays du Moyen Orient d'ou il s'est propage en Afrique et en Europe, du fait d'echanges de materiel contamine. En region mediterraneenne, RPW cause egalement des degats importants a Phoenix canariensis. Actuellement, il est signale dans 15% des surfaces cultivees en cocotiers et pres de 50% des surfaces cultivees en palmier dattier. Si les palmiers infestes ne sont pas detectes precocement et traites, ils meurent. Toutefois, les arbres infestes, traites precocement, repondent bien aux insecticides. La lutte integree contre le charancon a ete pratiquee dans plusieurs pays a l'aide notamment de pieges a pheromones. Toutefois, pour etre efficace, ce type de lutte necessite un depistage precoce de l'infestation. Dans l'absolu, il faudrait arreter le transport des jeunes plants a partir des regions infestees et d'un pays a l'autre. Quand cela apparait impossible, il faudrait imposer une quarantaine avant et apres le transport et seul du materiel contro le pourra etre transporte. Les programmes actuels de lutte integree par piegeage pheromonal pourront etre renforces par le recours a des ennemis naturels efficaces couple a l'utilisation de palmiers resistants au charancon. Cet article fait le point des travaux realises au cours des 100 dernieres annees sur RPW, dans les domaines de la biologie, des degats, de l'ecologie (cycle saisonnier, distribution spatiale, spectre alimentaire) et de la lutte integree (piegeage des adultes, lutte chimique, lutte biologique, lutte varietale et lutte autocide)