Impact of Zinc and Silica Solubilizing Bacterial Consortia on Soil Nutrient Availability and Direct Sown Paddy

Effect of zinc and silica solubilizing bacteria and their consortia on paddy was studied under field conditions at Agricultural Research Station, Janagamaheswarapuram, Andhra Pradesh. Thirteen treatments were assessed for availability of nutrients viz., Nitrogen, Phosphorus, Potassium, Zinc and Silica in soil and concentration of Nitrogen, Phosphorus and Potassium in plant at 45, 90 and 120 days after sowing (DAS).Significantly highest nitrogen (198.9, 262.3 and 240.2 kg ha-1), available phosphorus (36.7, 64.7 and 40.6 kg ha-1), potassium (221.4, 349.6 and 263.5 kg ha-1), zinc (0.86, 1.14 and 0.98 ppm) and silica (66.8, 98.9 and 84.8 ppm) were recorded in T13 (RDF + ZnKJJ-4 & ZnPGG-1 + SiKPP-1 & SiPYY-3) at 45, 90 and 120DAS, respectively. In the plant, nitrogen (0.89, 1.10 and 0.98 %), phosphorus (0.46, 0.67 and 0.58 %) and potassium (1.87, 2.29 and 1.98 %) were significantly highest at 45, 90 and 120DAS, respectively, in T13. There was increase in the available nutrient content upto90 DAS which then decreased at 120DAS. It is inferred that consortia of two zinc solubilizing and two silica solubilizing microorganisms (T13) is useful for increased availability of Nitrogen, Phosphorus, Potassium, Zinc and Silica in soil and increased uptake of NPK by rice plant, which in turn reduce exogenous chemical fertilizers.