PGPR bacillus species isolated from tomato plant –a comparative study on coconut water enrichment

Abstract

Plant growth promoting rhizobacteria (PGPR) are bacteria that colonize plant roots, they promote plant growth and reduce disease or insect damage. PGPR have been identified within many different bacterial taxa, most commercially developed PGPR for agricultural crops are species of Bacillus which form endospores that confer population stability during formulation and storage of products. Here the rhizobacteria Bacillus sp has been isolated from tomato plant and characterized with routine biochemical tests. Then the isolated rhizobacteria was enriched by inoculating with coconut water as carrier medium. The growth pattern was studied with the bacterial strain that was aseptically inoculated within coconut water in flask, coconut water within intact coconut and in nutrient broth. The rhizobacterial culture inoculated within coconut water in coconut has multiplied to the tune of 10.0×10 -6 cfu ml -1 within a period of 24 hrs. The bacterial strain developed mucoidal colonies on coconut water agar medium as a result of increased polysaccharide production. Seed colonization and plant growth promotion of tomato plant was more when culture was grown in coconut water was used for seed treatment.