STUDIES ON LEAF SPOT DISEASE OF MANGO AND ITS MANAGEMENT

Abstract

Mango (Mangifera indica L.) is susceptible to a number of diseases. One of the important diseases is leaf spot caused by Alternaria alternata affecting all the plant parts. The pathogen also attacks mango inflorescence resulting in a significant decrease in fruit set. The cultural characters of the pathogen were studied on Potato Dextrose Agar including the role of temperature and pH on the growth and sporulation. Certain fungicide and bioagents were evaluated for the control of the fungus. The temperature 25⁰C and pH 7.0 was found optimum for the growth and sporulation of Alternaria alternata. The fungicide Indofil M-45 was highly effective in inhibiting the mycelial growth at all concentrations followed by Ridomil at 0.5%. The bio agents Trichoderma harzianum reduced the growth of Alternaria alternata by 85.4% followed by T. viride, T. pseudokoningii, T. koningii , Aspergillus niger and A. flavus