SUMATHI, SREVATHI, K2016-06-072016-06-072011http://krishikosh.egranth.ac.in/handle/1/66946A poly bag experiment was conducted at Department of Agricultural Microbiology and Bioenergy and Inter faculty Department of Biochemistry, College of Agriculture, Rajendranagar, Hyderabad during 2010-11 to study the 􀀀Impact of biofertilizers on nutrient content and antioxidant activity of spinach beet (Beta vulgaris)”. The experiment was laid out in completely randomized design with 3 replications and 12 treatment combinations. Recommended dose of chemical fertilizers (100% RDF, 50% RDF), vermicompost and biofertilizers (nitrogen biofertilizer (NBF): Azotobacter and phosphate solubilizing biofertilizer (PSBF): Bacillus) were applied to the soil according to the treatments imposed. All green variety of spinach beet seeds (20) were sown in poly bags and watered regularly. The crop was harvested at 30 (1st picking), 45 (2nd picking) and 60 (3rd picking) days after sowing. At each picking, yield was noted, and fresh leaf samples were used for estimation of vitamin C content and total carotene content. Dry powdered leaf samples were used for estimation of total antioxidant activity, total phenols and mineral content. The physico - chemical properties of soil and microbial population in the soil were estimated before sowing and after harvesting of the crop. The shelf life of the leaf samples was assessed both at refrigeration and ambient temperature in 150 gauge polythene covers. The results revealed that the treatment receiving 50% RDF + NBF + PSBF recorded higher yield followed by 100% RDF, 50% RDF + NBF, 50% RDF + PSBF and vermicompost + 50% RDF. Dry weight was significantly higher on application with 50% RDF + NBF + PSBF which was on par with 100% RDF, 50% RDF + PSBF, 50% RDF + NBF and vermicompost with 50% RDF. The application of 50% RDF + NBF + PSBF resulted in higher vitamin C content over the other treatments at 30, 45 and 60 days after sowing. Low vitamin C content was recorded with vermicompost + NBF application and with PSBF application. Total carotene content was significantly higher with application of 50% RDF + NBF + PSBF at 30, 45 and 60 DAS over all other treatments. Calcium content was found to be significantly higher with the application of 50% RDF + NBF + PSBF followed by vermicompost with biofertilizers alone or combined and with 50% RDF. The lowest calcium levels were observed with only vermicompost treatment followed by 100% RDF. Iron content was found to be significantly higher with the application of 50% RDF + NBF + PSBF followed by vermicompost + 50% RDF and with two biofertilizers i.e., NBF and PSBF. Among all treatments total antioxidants were increased significantly with 50% RDF + NBF + PSBF which was on par with vermicompost + 50% RDF treatment. There was significant difference among 30, 45 and 60 days after sowing in the total antioxidant content. Significantly maximum total phenolic content was recorded in 50% RDF + NBF + PSBF followed by vermicompost + NBF + PSBF, vermicompost + 50% RDF and vermicompost + NBF. The lowest phenolic content in spinach beet leaves was found with vermicompost treatment and all other treatments showed significantly higher total phenol content. Shelf life was higher in the 50% RDF + NBF + PSBF treatment followed by vermicompost + NBF + PSBF, NBF + PSBF and vermicompost + 50% RDF both at refrigeration and room temperature in polythene cover. The soil pH was decreased with application of organic fertilizers and biofertilizers and EC was increased. The organic carbon content, nitrogen, phosphorus and potassium levels in the soil increased with 50% RDF + NBF + PSBF combination. Significatly higher soil microbial population was recorded with 50% RDF + NBF + PSBF treatment. Azotobacter and Bacillus population were higher in the treatments with biofertilizers alone or in combination, and with vermicompost. Lowest soil microbial population was recorded in 100% RDF. 50% RDF with NBF and PSBF was found to be the best among the treatments used in the present study as it resulted in the higher yield, vitamin C, total carotene, nutrient contents and antioxidant activity.enbiofertilizers, vermicomposting, fertilizers, bacteria, yields, organic fertilizers, vegetables, spinach, planting, inorganic acid saltsBeta vulgarisThesis