Antagonistic Effect of Fungal Bioagents against Alternaria porri (Ellis) Under In Vitro

Onion (Allium cepa L.) rightly called as “queen of kitchen” is one of the important vegetable crop grown in India. Among the several diseases, purple blotch diseases of onion (Allium cepa L.) caused by Alternaria porri (Ellis) is one of the most destructive disease causing accountable losses of about 80 to 90 per cent. Biological control is an important and integral part of integrated plant disease management system. Among the different bioagents evaluated in vitro against A. porri, all were found antifungal/antagonistic against the test pathogen. However, Trichoderma viride was found most effective with significantly highest mycelial inhibition (94.71%) of the test pathogen followed by Trichoderma harzianum (91.13%)and Trichoderma koningii (88.85%).