Effect of Various Nitrogen Sources and Antagonists on the Growth of colletotrichum Capsici (syd.) Butler and Bisby Causing Anthracnose of Yam (dioscorea Alata l.)

The yam crop was found infected with anthracnose disease caused by Colletotrichum capsici. In present investigation out of seven different nitrogenous sources tried, potassium nitrate proved to be the best for the growth (345.33 mg) and sporulation (380.3 spores/LPM) of the pathogen. Ammonium sulphate, Sodium nitrate and Ammonium nitrate also showed stimulation of growth and sporulation of C. capsici as compared to other sources tried. Also the result from the in vitro study revealed that nine antagonists viz., Trichoderma viride Pers. ex Grey, Trichoderma harzianum Rifai, Trichoderma longibrachyatum Rifai, Gliocladium virens Miller., Chaetomium globosum Kunze., Pseudomonas fluorescens Migula, Aspergillus niger Link, A. flavus and Bacillus subtilis Ell. were tested against C.capsici. by dual culture technique. In vitro studies on interaction of antagonists revealed strong antagonism of T. viride Pers., P.fluorescens MigulaAspergillus flavus Link.