A total of 125 actinomycetes isolates were
obtained from 25 rice field soil samples. All the isolates were screened for
antifungal activity against Fusarium moniliforme, Helminthosporium oryzae and
Rhizoctonia solani using in vitro dual culture bioassay. A total of 30 isolates
(24%) were displaying antagonistic activity against one or the other tested
plant pathogenic fungi. Seventeen actinomycetes isolates showed antagonistic
activity against Fusarium moniliforme, fourteen against Rhizoctonia solani and
fourteen against Helminthosporium oryzae. Two isolates R5 and Rf81 were
displaying antifungal activity against all the three tested fungi. Among the
antagonist isolates, seventeen were found to produce volatile compounds and
fifteen showed diffusible antimetabolite production. Out of these 30 isolates,
22 belonged to Streptomyces spp., 4 each to Micromonospora and Microbispora.
Four isolates (R5, R37, Rf2 and Rf81) were selected on the basis of their
antagonistic ability for field experiment . Highest inhibition of foot rot
disease was showed by R5 treatment in nursery (5.12%) and field (8.49%) over
control whereas the results of the nursery bed experiment with consortium of
R5, R37, Rf2 and Rf81 inoculation to rice seeds showed disease incidence of
6.41%. Therefore, these results suggested that actinomycete isolate R5 may be
used as a potential biocontrol agent against foot rot disease in Pusa basmati
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