INTEGRATED MANAGEMENT OF PHYTOPHTHORA DISEASES IN TROPICAL HORTICULTURE

The management of diseases caused by Phytophthora should be based on a sound understanding of the biology of the pathogen, including its modes of survival and dissemination, host range and the role of environmental factors in disease. Examples from our research on Phytophthora diseases of cocoa, coconut and durian illustrate the potential of integrated disease management. Care should be taken from the very beginning in the selection and preparation of land suitable for planting. Irrigation water for use in nurseries should be tested and kept free of the pathogen. Strict nursery hygiene must be imposed, and only disease-free planting material should be used. Potential vectors of the pathogen should be identified and their activities discouraged. Plant vigour should be managed by proper canopy management, water and nutrient management, hygiene and the use of composted manures and mulches. Organic soil amendments stimulate the activity of soil microbes, and suppress the survival and activity of Phytophthora. Fungicides such as phosphonate protect trees against infection, increase tree survival and yields, and have an important role in integrated disease management strategies.