Physiological and Biochemical Attributes of an Endophyte Stenotrophomonas maltophila, AVSW 1 Isolated from Chilli on PGP of Tomato

Abstract

This study aims to understand the role of Stenotrophomonas maltophilia AVSW 1, a chilli root endophytic bacteria, in promoting plant growth and fungal antagonism against Fusarium oxysporum in tomato. Ability of AVSW1 in terms of fungal antagonism, SEM analysis of root colonization, growth optimization and enhancement of the production of Indole-3-aceticacid, Ammonia and siderophore, and phosphate solubilisation followed by in vitro plant growth promotion of tomato using seed bacterization were evaluated. using GC-MS and HPLC analysis of volatile compounds and secondary metabolites of AVSW1was also studied. AVSW1 showed 26.3μg/ml of Ammonia production, 19.33 μg of IAA production, 60.67 psu of Siderophore and 91.67ppm of phosphate solubilisation under optimised growth conditions(350C, pH7,1% NaCl,1% Fructose, 1% Peptone and 60 h incubation).Growth parameters like root length, shoot height, no. of leaves and lateral roots, biomass, and protein and carbohydrate are much higher in AVSW 1 inoculated plants compared to untreated control .GC-MS analysis revealed that 2-Pentanone,4-Hydroxy-4-methyl, Cyclopropane,1-(1-Methylethyl)-2-Nonyl-Glycine, N-Acetyl-N(Trifluoroacetyl), MethylEster2-Acetoxy Isobutyryl Chloride, propanoic Acid, 2-Oxo-, Methyl Ester Pentanoic Acid 4-Oxo,5-Hydroxy pentane hydroxyl amine Ethanol,2-(Octyloxy), 2-Cyclopenten-1-One, 2-Hydroxy-3,4-Dimethyl and 2,2- Di methyl tetrahydro pyran-4-ol are pivotal compounds of S. maltophilia AVSW1 responsible for fungal antibiosis and root colonization to promote growth in tomato seedlings.