General Overview of Genetic Research & Experimentation on Coconut Varieties Tolerant/Resistant to Lethal Yellowing Diseases Survol Général de la Recherche et de l’Expérimentation sur les Variétés Résistantes/Tolérantes au Jaunissement Mortel

The Lethal Yellowing disease is one of the main threats to coconut industry in many parts of Africa and the Caribbean. Planting resistant varieties has long been recognized as one of the most promising ways of controlling it. Considerable efforts have been devoted throughout the world to screening suitable varieties and have often involved international co-operation. It has proven to be a lengthy and difficult task. We present an overview of these efforts with special mention to Ghana, Jamaica and Mexico. Although no variety so far has been proven fully and permanently resistant, treating resistance level as a threshold trait makes it possible to demonstrate significant differences among varieties, which can be exploited effectively to make genetic improvement a component of an integrated control strategy. Based on past experience, we make a few suggestions to increase the diversity of resistance sources and increase the level and the sustainability of resistance to LY in coconut.