Integrated management of Phytophthora disease of jackfruit in the Southern Philippines

Jackfruit is a 'flagship commodity' in Eastern Visayas but its production is hampered by an unidentified disease manifested by a decline syndrome. This project aims to improve the productivity of jackfruit in the Philippines by increasing the understanding of Phytophthora diseases among industry stakeholders, enhancing the diagnostic capacity of local scientists and through the development of a range of effective integrated disease management options for farmers. Specifically, the project aimed to: identify key constraints to jackfruit productivity, diagnose jackfruit decline, implement farmer trials disease management strategies and evaluate and implement a limited series of disease management options designed for farmers of various background and capacity. For capacity building, the Filipino counterparts were trained on Phytophthora diagnosis and species identification. A participatory action research (PAR) approach was done to study disease otiology, mode of dissemination, interaction with other pathogens and to evaluate a series of disease management options in the nursery and orchard. Based on morphology and DNA characteristics most of the isolates where identified as Phytophthora palmivora. Other Phytophthora species and Pythium species are also associated with the disease. Insects have a role in Phytophthora dissemination to trees. Based on Phytophthora nematode-Fusarium interaction study, Phytophthora alone is the primary cause of jackfruit decline. PAR results have shown the efficacy of organic amendments in the form of fermented organic additives (FOA) composed of chicken dung, green silage and effective microorganisms in potting media mixes to reduce seedling mortality due to phytophthora. In the orchard, improved cultural management strategies such as tree mulching and Gliricidia and banana, pruning, construction of drainage canals, mounting with mudpress/chicken dung and mudpress/vermicompost and phosphonate stem injection, phosphonate plus pentrabark spray, chitosan, benzothiodiazole and aspirin sprays are effective in reducing the incidence and severity of the disease. A limited series of management options have been formulated from the results for other farmers of various background and capacity.