Evaluation of efficacy of antagonistic Trichoderma isolates against Sclerotium rolfsii under in vitro

Abstract

Fifty rhizosphere Trichoderma isolates (GT1 to GT50) were isolated from groundnut rhizosphere soil. When these isolates were screened against Sclerotium rolfsii in dual culture technique, Trichoderma isolates GT-9, 28, 34, 38 and 49 showed highest inhibition. These isolates overgrew over the pathogen at six days after incubation and lysed the hypha of the pathogen. The inhibitory effect of volatile compounds was maximum when S. rolfsii paired with Trichoderma isolate GT-9 (55.2%) followed by Trichoderma isolate GT-38 (51.1%) and Trichoderma isolate GT-28 (43.3%). Culture filtrate studies showed that maximum inhibition was shown by Trichoderma isolate-9 (54.4%) followed by Trichoderma isolate-34 (50.0) and Trichoderma isolate-28 (41.1).