Antagonistic potential and molecular characterization of Trichoderma asperellum against Rhizoctonia solani AG-3 causing black scurf of potato

Rhizoctonia solani Kuhn (AG-3) is a soil borne pathogen present ubiquitously and causes black scurf of potato worldwide. Considering the importance of the disease, the present study was first carried in vitro and then under field condition using three isolates each of Trichoderma spp. (T₁, T₂ and T₃) and Pseudomonas fluorescens (P₁, P₂ and P₃) to assess the use of these antagonists against the black scurf pathogen. Study revealed that Trichoderma isolate T₁ showed 58.25% percent mycelial growth inhibition of R. solani as compared to bacterial antagonist in vitro and 87.98%, 84.41% reduction in disease severity in vivo and in greenhouse, respectively. Specific results for fingerprinting of the most effective antagonist isolate T1 were obtained by using 15 primers of SSR and 2 primers of ITS (ITS1 and ITS4). The molecular identification of most effective Trichoderma isolate (T1) revealed it as Trichoderma asperellum.