Potential of Plant Growth Promoting Bacteria on Nutrient Availability in Soil, Nutrient Uptake and Yield of Summer Groundnut Grown on Entisol

A field experiment was conducted during the year 2017-18 at Post Graduate Institute Farm, Mahatma Phule Krishi Vidyapeeth, Rahuri. The experiment was laid out in Randomised block design with three replication and eleven treatments. The treatments comprised of T1: Absolute control, T2: only ZnSB, T3: GRDF(25:50 kg ha-1 N:P2O5 + FYM @ 5 t ha-1), T4 to T7 were GRDF + 100%, 75%, 50% and 25% RD of Zn through ZnSO4+ ZnSB and T8 to T11 were GRDF + 100 %, 75%, 50% and 25% RD of Zn through ZnO + ZnSB. The biofertilizer zinc solubilizing bacteria was given as a seed treatment as well as soil drenching @ 5% at 30 days of sowing. The soil pH, EC, organic carbon and calcium carbonate content in soil at initial as well as at harvest did not find any differences amongst treatments. The available N, P and K status of soil at harvest were found to be significantly improved due to application of 100% Zn through ZnSO4 along with ZnSB and GRDF. The DTPA-Fe, Zn, Mn and Cu status of soil at harvest was also found to be significantly increased due to application of 100% Zn through ZnSO4 + GRDF. Total uptake of nitrogen, phosphorus and potassium by groundnut crop was significantly increased (132.29, 15.60 and 65.63 kg ha-1, respectively) due to application of 100% Zn through ZnSO4 + ZnSB along with GRDF. The same trend was also observed in above treatment in respect of total uptake of Fe, Zn, Mn and Cu (1352, 377, 619 and 67 g ha-1, respectively). The oil per cent was significantly increased in treatment of T4 (40.96 %) over all the treatment. The pod yield of groundnut was significantly increased in treatment of T4 (30.63 q ha-1) over all the treatments except treatment T5 (29.44 q ha-1) which was at par with T4. Haulm yield of groundnut was significantly increased (62.70 q ha-1) in treatment of T3 (100% GRDF (25:50:00 kg ha-1 N:P2O5 + FYM @ 5 t ha-1) over all the treatments. It can be thus concluded that, the application of 100% recommended dose of Zn through Zinc sulphate @ 20 kg ha-1 + 5 % ZnSB to seed treatment at sowing and through drenching at 30 DAS along with 100% recommended dose of nutrients (25:50 kg ha-1 N:P2O5 + FYM @ 5 t ha-1) to summer groundnut was found beneficial for increased in available macro and micronutrients status of soil, total uptake of macro and micronutrient.