CONTROL OF FUNGAL SPOILAGE IN ALPHONSO MANGOES BY PRE-HARVEST APPLICATION OF FUNGICIDES
One of the most serious causes of spoilage of mango fruit is incipent fungal infection, noticed particularly in grafted varieties, at different stages of fruit development. The causal organism occurs insitu and the fruits which appear normal at the time of harvest, suffer spoilage during the ripening process. The spoilage is essentially due to stem-end rot, lateral rot and anthracnose in the southern region; and sooty mold infection is common in coastal areas. Alphonso mango is one of the most popular varieties grown and marketed in the southern region and spoilage due to fungal infection is of the order of 25–30 per cent in this variety.
Spraying with copper and sulphur fungicides is generally recommended as a prophylactic measure. Copper fungicides have certain limitations in that they leave a residue on the surface of plant parts, and repeated spraying results in copper toxicity and leaf necrosis. Orthocides have come into use in recent years for the control of fungal diseases in a variety of crop plants and the results obtained are highly satisfactory. Captan fungicide unlike metallic fungicides has an advantage in being highly compatible with insecticides and growth regulators. Also, the fungicide is higly effective at low concentrations, has high tolerance level to plants and low toxicity to mammalian tissues. It was, therefore, thought pertinent to study the effect of these fungicides on the incidence of fungal spoilage, the residual level, as well as the quality of fresh fruit and processed products.