Biological control of paddy brown spot caused by Bipolaris Oryzae (Breda de Haan)

The antibiotic potentially of the soil fungi was studied in paddy field . The test pathogen Bipolaris oryzae varied in its sensitivity to the metabolic growth products of antagonisitic fungi. Invitro screening using the dual culture technique was undertaken to assess the potential of nine fungal species such as Aspergillus niger, A. fumigates, A .flavus A. sulphureus , A. terreus, Penicillium chrysogenum, P. janthinellum, Trichoderma viride and T. harzianum as biological control agents against Brown spot fungus Bipolaris oryzae. Results revealed that all the test antagonists effectively checked the growth of the pathogen. The test antagonists grow faster than the pathogen and produced inhibition zones thereby limiting the growth of the pathogen has been discussed.