Pyocyanin is a blue green phenazine pigment produced in large quantities by active cultures ofPseudomonas aeruginosa, with advantageous applications in medicine, agriculture and for the environment. Hence, in the present study, a potent bacterium was isolated from agricultural soil and was identified morphologically and by 16S rRNA sequencing as P. aeruginosa (isolate KU_BIO2). When the influence of nutrient supplements in both King's A and Nutrient media as amended was investigated, an enhanced pyocyanin production of 2.56 µg ml −1 was achieved in King's A medium amended with soya bean followed by 1.702 µg ml −1 of pyocyanin from the nutrient medium amended with sweet potato. Purified pyocyanin was characterized by UV-Vis Spectrophotometer and Fourier-Transform Infrared spectroscopy (FTIR). Furthermore, Liquid Chromatography Mass Spectrum (LCMS) and Nuclear Magnetic Resonance (NMR) confirmed its mass value at 211 and as N-CH 3 protons resonating at 3.363 ppm as a singlet respectively. The isolated pyocyanin displayed remarkable dye property by inducing color change in cotton cloth from white to pink. Lastly, the antifungal activity of test pyocyanin showed inhibition of growth of rice blast fungus, Magnaporthe grisea and bacterial blight of rice, Xanthomonas oryzae at concentrations of 150 and 200 ppm, respectively. Thus, this investigation provides evidence for diverse actions of pyocyanin which are nutrient dependent and are capable of acting on a large scale, by utilizing microbes existing in agriculture wastes, and thus could be used as an alternative source in the making of natural textile dyes with strong durability and a broad spectrum of ecofriendly agrochemicals.Microorganisms are biological agents which help to solve many problems related to health, agriculture and the environment 1-3 . Microorganisms have been the study at interest in recent years because of production of novel secondary metabolites 4 . These metabolites exhibit antimicrobial, antiviral or antitumor as well as anticoagulant properties, and the production of secondary metabolites may have evolved as an alternative strategy to switching off metabolic pathways by various control mechanisms 5-7 . Products of secondary metabolism, such as pigments, could also be of considerable selective advantage since they could eliminate possible microbial competitors 8 .Natural pigments have been obtained and used since long ago, but interest in them has decreased due to toxicity problems. Hence, pigments from microbial sources are good alternatives for various applications 9,10 . Pseudomonas aeruginosa is one of the most commercially valuable organisms, many of which are responsible for producing soluble pigments like pyocyanin (blue), pyoveridin (yellow-green), pyorubin (red) and pyomelanin (brown) 11 . P. aeruginosa produces pyocyanin (N-methyl-1-hydroxyphenazine) which is a water soluble

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.

Plant Growth Promoting Rhizobacteria (PGPR), a microbial biostimulant has been widely studied to stimulate plant growth through induction of natural biological processes. However, lack of successful validation under open field remains a barrier to mark their standard in agriculture. Therefore, the aim of the research was to highlight the potential of PGPR biostimulants via in vitro studies and subsequently to demonstrate the in planta evaluation in oilseed crop, Arachis hypogaea L. (Groundnut) under pot and field trials. The two rhizobacterial strain was identified as Pseudomonas fluorescens and Bacillus subtilis by 16s rRNA gene sequence analysis. Both the strains were functionally screened for plant growth promoting traits. Pot and field trials were conducted where seeds were inoculated with PGPR biostimulants and harvested at 30 and 90 days. Biostimulant treatments were applied as single and co-inoculation in groundnut and the growth factors, biochemical parameters, yield, and seed quality were analyzed. The study inferred that the consortium of PGPR biostimulants significantly (p < 0.05) showed highest growth, photosynthetic pigments, nodulation status, leghaemoglobin content, yield attributes, and also biofortification of seed nutrients in oilseed crop under both pot and field conditions than un-inoculated control. This study supports the idea of the application of PGPR as microbial biostimulants through successful open field trial to facilitate its implementation as a feasible and potential agricultural product to synthetic fertilizers thereby influencing sustainable and stable crop production.

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Objective: The main objective of this study was to determine the effect of biocontrol Trichoderma species agent against Fusarium oxysporum in Solanum lycopersicum L. Methods: Genus Trichoderma effective biocontrol agent against fungal, bacterial pathogen. The fungal isolates Trichoderma viride (Tr01), Trichoderma harzianum (Tr02), and F. oxysporum (Fu04) were also identified through morphological characterization observed under a light microscope (10x×40x). The isolates (Tr01, Tr02, Fu04) were confirmed through genetic DNA isolation and polymerase chain reaction analysis. After that pot culture study was conducted to test the antagonistic potential (Tr01, Tr02) and against (Fu04). Seeds of tomato (S. lycopersicum L.) were used in this experiment; treatment such as control, Tr01, Tr02, Fu04, Tr01+ Fu04, and Tr02+ Fu04 was given to the seeds sown in pots and maintained in appropriate distances. Results: In pot culture after 45th day after inoculation of bioinoculated plant (Tr02), significantly enhances plant length, fresh weight, dry weight, chlorophyll content, nitrogen content, NPK content, and soil microbial population. Conclusion: In this experiment, Trichoderma spp. to control plant pathogen and improve yield and quality of crop. Fungal species belonging to the genus Trichoderma act as a biological agent. Bioinoculated plant (Tr02) significantly enhances plant growth ability to with stand under nutrient deficient conditions.