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Not AvailableLow native soil phosphorus (P) availability coupled with poor utilization ef®ciency of added P is a major constraint limiting the productivity of soybean±wheat system on Vertisols in Indian semi-arid tropics. The use of fertilizer P is limited by its high cost, while organic inputs generally cannot provide suf®cient P for optimum crop growth due to their low P concentration. We, therefore, evaluated in a 5-year ®eld experiment (1992±1997) the effects of integrated use of manure and fertilizer P on crop yield sustainability, P utilization and soil P fertility under soybean±wheat system on a Typic Haplustert. The treatments consisted four rates each of manure (applied only to soybean) and fertilizer P (applied to both soybean and wheat) arranged in a split-plot design with four replications. Both soybean and wheat crops responded signi®cantly to the application of manure and fertilizer P. For the same level of P input, the yield increases were greater with manure P than with fertilizer P. Further, integrated use of fertilizer P and manure was better than their sole application in increasing and sustaining the productivity of soybean±wheat system. The P uptake by the crops increased with increasing rates of manure and fertilizer P and was relatively larger in soybean than in wheat. The per cent phosphorus recovery by the crops from fertilizer P decreased with increasing fertilizer P rate, while it was improved in the presence of manure. Though the extent of fertilizer P recovery was more or less similar in both the crops, soybean was more ef®cient than wheat in extracting the soil and manure P. The available P status of the soil showed a signi®cant build-up during successive cropping seasons due to fertilizer P and the increase was strikingly greater when fertilizer P was applied in combination with manure. The integrated use of manure and fertilizer P is a promising strategy to improve soil P fertility status and to obtain higher and sustained productivity of the soybean-wheat cropping system on Vertisols of the semi-arid tropics. # 1999 Elsevier Science B.V. All rights reserved.Not Availabl