Vol. 11, Issue 8 (2022)

Author(s):
Pawar GS, Gholve VM and Navale MD

Abstract:
Present investigations were carried out to study in vitro efficacy of antagonists and aqueous extracts of botanicals against S. rolfsii Sacc inciting stem rot of groundnut. Six fungal, two bacterial antagonists and aqueous extracts of the 8 botanicals were evaluated against S. rolfsii Sacc in vitro. The results revealed that all the eight antagonists caused significant inhibition of mycelial growth of the test fungus. However, maximum inhibition of mycelial growth was obtained with B. subtilis which was most effective with least linear mycelial growth (35.32 mm) with highest mycelial inhibition (60.76%) of the test pathogen and significantly superior over all the bioagents tested. The second and third best antagonists found were T. Asperellum (41.47 mm and 53.93%) and T. harzianum (53.93 mm and 50.00%) and T. koningii was found least effective with 86.40 mm linear mycelial growth and 4.00 percent mycelial inhibition, respectively. All the evaluated botanicals (each @ 15 and 20%) were found antifungal to S. rolfsii Sacc. However, on the basis of highest average mycelial growth inhibition recorded at 15% conc., A. sativum (90.89%), followed by O. sanctum (83.61%), A. racemosus (73.94%), Vitex spp. (45.56%) and A. cepa (35.78%). The botanicals A. indica (1.86%) and C. longa (1.78%) were found comparatively less effective. At 20% conc., A. sativum (93.81%), followed by O. sanctum (90.77%), A. racemosus (82.94%), Vitex spp. (56.22%) and A. cepa (53.66%). The botanicals A. indica (25.32%) and C. longa (25.00%) were found comparatively less effective.