Integrated Management of Coconut Lethal Yellowing Phytoplasma Disease in Mozambique: Current Challenges and Future Perspectives

Abstract

The coconut palm (Cocos nucifera), an importance cash and subsistence crop, is widely grown in the coastal regions of the tropics, and contributes to a large extend to the livelihood and food security of millions of rural inhabitants in Mozambique. However, coconut production has been challenged by the occurrence of an invasive and emerging pathogen, the causal agent of lethal yellowing disease (LYD). Mozambique was traditionally the top coconut producer in Africa and is now ranked fourth below Nigeria partially due to coconut LYD. The current LYD epidemic status in Mozambique expanded the typical plant-insect vector-phytoplasma triangle to a plant-insect vector-phytoplasma-beetle relationship. For LYD management, more effort must be directed towards preventive measures, since the infection is usually lethal. However, several measures aiming at maintaining the LYD pressure at low levels, can be combined. The integrated LYD strategies described in this chapter include the use of all available management strategies to maintain disease level under control, while minimising the use of chemicals. Currently, the top options for LYD management in Mozambique involve combination of plant resistance and cultural practices. The LYD field tolerant Mozambican tall (MZT) variety is widely used to replace the succumbed LYD-infected coconut palms. Black’s approach for LYD management could be improved by including early field detection using LAMP technology to ensure that not only symptomatic palms, but also infected symptomless plants are felled and burnt. The integrated LYD management approach, targeting the LYD pathosystem and the coconut beetle Oryctes monoceros as the major coconut pest, is likely to successfully control the current epidemics in Mozambique.