Antifungal activity of bacillus species isolated from agriculturally cultivated soils against fungal phytopathogens fusarium udum and rhizoctonia solani affecting paddy and pigeon pea crops

The present research was conducted to test antifungal properties of soil bacteria. Soil plant microbe interactions are complex and there are many ways the outcome can influence plant health and productivity. These interactions may be detrimental, beneficial, or neutral to the plants. However, the focus of this work is to exploit the beneficial bacteria to enhance plant growth by biocontrol of fungal phytopathogens by different mechanisms. Fusarium udum and Rhizoctonia solani are soil borne fungal phytopathogens that affect paddy and pigeon pea crops in the early stages of cropping practices. Soil borne bacteria are well known for their antagonism, predation, and competition towards other microbes in consortia. These bacterial traits of antagonism and competition could suppress fungal phytopathogens enabling a sustainable method of crop protection and forfeits the classical chemical crop protection methods. Bacterial isolates such as Bacillus species present in enormous percentage in agriculture soils were isolated and tested for PGPR and fungal antagonistic traits. Eight bacillus species were tested for volatile HCN and Ammonia production, enzymes such as cellulase, proteases, chitinase productions, siderophore production. These bacillus species were further tested for fungal phytopathogen suppression in both qualitative and semi- quantitative method using dual plate assay methods. Bacillus thuringenesis and Bacillus cereus were found to suppress phytopathogens by inhibiting their growth both in vitro and in vivo methods. Hence these species of Bacillus enable the biocontrol methods of plant disease suppression.