EFFECT OF GAMMA IRRADIATIONS ON FUNGAL GROWTH OF MANGO (MANGIFERA INDICA) TO ENHANCE THE SHELF LIFE.

Abstract

The main objective of this research was to find the effect of Gamma irradiations and UV-C irradiations on the storability of mango fruit to check the prevention of fungal growth and the formation of skin scald. Gamma irradiations had showed the limited growth of microbes, delay of ripening and extension in the shelf life of mango fruit. From the surface of mango different thirteen fungal species were isolated. Different irradiation doses (0.50, 1.00 and 1.50 kGy) along with hot water were applied on the surface of mangoes and stored for 60 days. After treatment, the samples were collected and cultured on different media for growth and identification of fungi. Mangoes treated with gamma irradiation dose (1.5KGy) showed better shelf life than other treatments for controlling the decay of mangoes and enhancing the shelf life. Reduction in the disease incidence had been achieved with relatively high dose of gamma irradiations. However high dose of irradiations had adverse effects on texture and other qualities, but these effects can be reduced by using combined treatments of radiations plus low temperature. Several aflatoxin producing fungal species including Aspergilus flavus, A. fumiigatus, A. niger, Penecillium chrysogenum, P. brevicompactum, P. verucosum, P. oxaliicum, Cladosporum cladosporoides were isolated from mango surface and their isolation frequencies were observed.  Gamma irradiations at 1.50 KGy showed best results to remove fungal isolates when it was applied on mango surface for two hours and fifteen minutes.