Effect of P solubilizing microorganisms on yield of rice and nutrient availability in an acid soil of Mizoram

A field experiment was conducted for three consecutive kharif seasons during 2000–2002 at Kolasib, Mizoram to study the effect of application of graded doses of rock phosphate along with P solubilizing microorganisms on yield of rice and nutrient availability in an acid Inceptisol. The results revealed that the grain yield was significantly increased with rock phosphate application up to 90 kg P₂O₅ ha⁻¹. Highest grain yield was recorded with the inoculation of P solubilizing bacteria in combination with rock phosphate @ 60 kg P₂O₅ ha⁻¹. A significant improvement in organic carbon and available NPK was also observed with the combined use of rock phosphate and P solubilizing microorganisms. The results indicated that bacterization of seedlings in combination with optimum dose of rock phosphate produced highest and sustainable crop yields, maintained the soil health and minimized the expenditure on P fertilizer cost to an extent of 30–40%.