Gangwar, MadhuramaHarpreet Kaur2017-05-162017-05-162017http://krishikosh.egranth.ac.in/handle/1/5810011217The present study was undertaken with a view to isolate phosphate solubilizing bacteria (PSB) from potato field soil and evaluate their potential to produce plant growth promoting metabolites and increase the crop yield. Phosphate solubilizing bacteria (PSB) are frequently used as plant growth promoters and their use as inoculants increases P uptake by the plant and enhances crop yield. A total of 40 PSB isolates were obtained from the rhizospheric soil of potato. The functional potentialities of the isolates recorded were phosphate solubilization, siderophore and Indole acetic acid (IAA) production. The maximum P-solubilization and IAA production was recorded for isolate DS-20 (45.28 mg /100 ml and 80.12 µg/ml) respectively. Isolate DS-5 exhibited maximum catechol type (78.8µg/ml) and hydroxamate type (43.56 µg/ml) of siderophore production. A field experiment was conducted to evaluate the tuber yield and quality characteristics in response to three phosphorus levels (0, 75 and 100 kg/ha) and two PSB cultures (DS 20 and Reference culture). The crop growth (sprout number, plant height, leaf area, chlorophyll content) and yield traits (tuber yield, NPK contents of plant, tuber and soil) enhanced on PSB inoculation as well as increased P-fertilizer application. Maximum tuber yield of 375 q-1 hectare was produced by Reference culture. Therefore, PSB inoculants may act as potential P-biofertilizer for the sustainable potato cultivation system.ennullThesis