ABSTRACT
To know the efficacy of bio-control agents on growth of Sclerotium rolfsii causing stem rot of groundnut, an in vitro study was conducted in the Department of Plant Pathology, Agricultural College, Bapatla. For this, three Trichoderma spp., two Pseudomonas fluorescens isolates and one Bacillus subtilis were selected as biocontrol agents. We observed that, there is a significant difference among all the treatments. The lowest radial growth (1.9 cm) and highest per cent inhibition (79.26%) were recorded with T. viride PDBC isolate followed by T. harzianum 4 (2.3 cm and 74.81%) and Trichoderma harzianum PDBC (2.6 cm and 70.74%) isolates, respectively. Among the bacterial isolates, lowest radial growth (4.6 cm) and highest per cent inhibition (48.89%) of S. rolfsii were recorded with Bacillus subtilis PDBC isolate. But the highest radial growth (7.6 cm) and lowest per cent inhibition (15.56%) was recorded with P. fluorescens SPA1 isolate.