Siderophores are low molecular weight secondary metabolites produced by microorganisms under low iron stress as a specific iron chelator. In the present study, a rhizospheric bacterium was isolated from the rhizosphere of sesame plants from Salem district, Tamil Nadu, India and later identified as Bacillus subtilis LSBS2. It exhibited multiple plant-growth-promoting (PGP) traits such as hydrogen cyanide (HCN), ammonia, and indole acetic acid (IAA), and solubilized phosphate. The chrome azurol sulphonate (CAS) agar plate assay was used to screen the siderophore production of LSBS2 and quantitatively the isolate produced 296 mg/L of siderophores in succinic acid medium. Further characterization of the siderophore revealed that the isolate produced catecholate siderophore bacillibactin. A pot culture experiment was used to explore the effect of LSBS2 and its siderophore in promoting iron absorption and plant growth of Sesamum indicum L. Data from the present study revealed that the multifarious Bacillus sp. LSBS2 could be exploited as a potential bioinoculant for growth and yield improvement in S. indicum.

Siderophores are iron chelator low molecular weight secondary metabolite produced by microorganisms found in limited iron environment. In this study, a bacterium capable of secreting siderophores was isolated from the iron deficiency rhizosphere agriculture soil from Salem district, Tamil Nadu, India. The isolate was identified as Bacillus subtilis(LSBS2) based on biochemical characteristics and 16S rRNA gene sequences analysis. The siderophores production ability of the strain was evaluated qualitatively and quantitatively through Chrome Azural S assay. The TLC analysis of the LSBS2extract developed brown colour spots indicating catacholate type of siderosphore of isolate had the ability to produce 20 mg L -1 of siderophores in liquid medium. Further, the siderophores was partially purified and identified as bacillibactin type using HPLC, FTIR and the bacillibactin structure was confirmed by 2D-NMR analysis. Furthermore, a field experiment was conducted with Arachis hypogaea to assess the inoculation effect of LSBS2 on plant growth and other physico-chemical parameters. Inoculation of LSBS2 increased plant biomass, pigment content, nutrients, Iron content and oil content than the uninoculated control. The present result suggested that the occurrence of bacillibactin type siderophores in strain LSBS2 play a key role in iron chelation and favors the healthy growth of Sesamum indicum. Therefore, the strain LSBS2 could be exploited as a potential bioinoculant for stimulating peanut plant immunity.

Production of the crop is affected by deficiency of fertilizers and low number of plant growth promoting rhizobacteria in soil. Pseudomonas fluorescens isolated from soil characterized and evaluated in Arachis hypogaea Pannapatti Salem,Tamil Nadu.Nigella sativa (Kolinji) Periyar University Salem,Tamil Nadu. were isolated and the isolates was named as (PSO1and PSO2)Bio chemical characterized showed that the isolates were acid procedures and positive to catalase and nitrate reductase production and do not have hydrogen sulphide production .The isolates were the amount of phosphate solubilization andsiderophores production by Pseudomonas fluorescens compared to isolates (PS01 and PS02).Maximum activity shows in PS01.The isolates were identified by biochemical test confirmed with genomic DNA identification. Arachis hypogaea seed with Pseudomonas fluorescens PS01 for plant growth promoting activities in green house showed a positive result. This isolates increased Arachis hypogaea leaves number, branches number, root length, and shoot length number of nuts also increased. In conclusion that the use of Pseudomonas fluorescensPS01 isolates could increase the Arachis hypogaea growth and yield performance. This isolates can used as potential bio fertilizers and plant growth promoter.