QUALITY PROBLEMS IN IMPORTANT FRUIT CROPS IN ASEAN

Quality problems which diminish the competitiveness of ASEAN fruits in target export markets include decay and physiological disorders. Late nt diseases originate in the field, but become evident only after harv est. Factors which induce physiological disorders, on the other hand, are principally postharvest in origin. However, predisposing condition s might occur during fruit growth and development. Fruit crops importa nt to ASEAN include the banana, pineapple, mango, rambutan, papaya and durian. Although disease problem, principally, anthracnose and stem e nd rot constitute a major problem in these fruits, causative organisms have been identified and control measures formulated. In contrast, ph ysiological disorders, which lead to quality deterioration and limit t he marketable life of these fruits, are not as well understood. Hypoxi a, particularly if combined with threshold levels of ethylene and temp erature extremes can lead to a variety of these disorders. Quality pro blems arising from physiological disorders of mango, rambutan, papaya and durian, as well as etiological aspects are discussed.