Effects of Chitosan and Plant Extracts on Growth of Colletotrichum gloesporioides, Anthracnose Levels and Quality of Papaya Fruit

The fungicidal effect of chitosan and aqueous extracts of various plants on the development of the fungus that causes anthracnose in papaya was studied. Chitosan applied at 2.0% and 3.0% was effective against Colletotrichum gloeosporioides. Extracts of custard apple, papaya leaves, and papaya seeds alone had no effect, but 2.5% chitosan combined with all tested extracts had a fungistatic, not fungicidal, effect. Chitosan affected the conidial morphology of C. gloeosporioides after 7 h incubation. In situ anthracnose control was achieved with 1.5% chitosan. Chitosan usage did not affect papaya fruit quality in terms of weight loss during storage; fruit treated with papaya seed extract, either alone or in combination with chitosan, was firmer than untreated fruit.