VEENA. S. ANILSWATI2023-01-142023-01-142022-12-29https://krishikosh.egranth.ac.in/handle/1/5810192287ThesisExcessive application of inorganic fertilizers and agrochemicals is creating environmental pollution and contributing to climate change. To mitigate these negative effects, eco-friendly alternatives are needed and compost tea is one of them. The present study demonstrates that under organic cultivation of groundnut variety TMV2, seed treatment (ST) with non- aerated compost tea (NCT) followed by foliar sprays showed highest plant height (26.92 cm), fresh weight (72.2 g), significantly higher POX (127.85 μg/min/mg protein) and SOD (24.76 μg protein for 50% inhibition) activities and significantly higher yields over control. The study also isolates PGPRs from compost tea and characterizes earlier isolated nitrogen fixers and phosphate solubilizers. The most prominent 6 bacterial isolates capable of producing high levels of phytohormones IAA, GA, cytokinins were identified by sequencing. Liquid microbial consortia were prepared using shortlisted 6 isolates in different combinations and further evaluated for their beneficial effects on groundnut plants under greenhouse conditions. Among the treatments consortia NPF (combination of all six isolates) significantly enhanced biomass, POX, SOD activities, phenolic and flavonoid levels, and yield compared to positive controls-NCT and ACT. GC-MS analysis of the metabolomic profile showed several unique benificial metabolites secreted by bacterial isolates and groundnut leaves treated with consortia, having putative roles in plant growth promotion and as antimicrobials and antioxidants. Thus, compost tea is a simple, stable, eco-friendly and cost-effective technique that farmers can include in organic agronomical practices. Compost tea and consortia developed in this study will benefit the farmers by providing an alternative method for groundnut production.EnglishThesis