The importance of integrated phosphorus management in pulses and scanty work done on different pools and fractions of phosphate and its transformation with different source of applied phosphorus, it is important to investigate the behaviour of phosphate in soil with respect to application of different fertilizers/ manures along with biofertilizers and contribution of different fractions and forms towards P nutrition of green gram and evaluation of various extractants for determining available P and establishing critical limit of available P for green gram. Therefore, the present investigation entitled, ?Influence of integrated phosphorus management on phosphorus transformation, availability and its critical concentration in green gram (Vigna radiate L.)? was undertaken with the following specific objectives. To isolate and characterize phosphorus-solubilizing microorganisms(PSB) from rhizosphere. To study the effect of organic and inorganic source of P on nutrient (NPK) availability and optimum yield potential. To study the integrated effect of P sources on P transformation and To workout the suitable extractants for available P and its critical limit in soil and plant.