Isolation and characterization of antagonistic microorganisms from Chloris barbata and Heteropogon contortus

Rhizosphere micro-flora of two grasses, Chloris barbata and Heteropogon contortus was studied and their ability to suppress phytopathogens (Curvularia lunata and Fusarium oxysporum) was evaluated during present investigation. From the rhizosphere of Chloris barbata 4 bacterial and 14 fungal species, whereas from Heteropogon contortus 4 bacterial and 11 fungal species were isolated. Among them Trichoderma harzianum, Penicillium decumbens, Purpureocillium lilacinum, Mucor racemosus and Penicillium citrinum were identified as effective against both of the pathogens i.e. Fusarium oxysporum and Curvularia lunata. 16S rRNA sequencing revealed that the moderately effective antagonistic bacterial isolates were Staphylococcus hominis strain 309-4 and Bacillus proteolyticus strain H8. In vitro study undertaken on these isolates indicated that these microorganisms can be used as biocontrol agents against Fusarium oxysporum and Curvularia lunata.