Soil test crop response (STCR) field experiments were conducted on tomato (Lycopersicon esculentum Mill.) during Rabi 2003–04 under irrigated situations in Alfisoils at Palem, Mahbubnagar district, Andhra Pradesh with the objective of developing soil test based fertilizer recommendations with or without use of organic manure (FYM). The results of experimentation indicated that 1.82 kg N, 0.22 kg P2O5 and 2.05 kg K2O were required to produce one quintal of tomato fruit yield in Alfisoils under irrigated conditions. The contributions (%) from soil and fertilizer nutrients in an Alfisoil were found to be 26.79 and 11.79 for N, 14.08 and 12.39 for P2O5 and 30.30 and 30.08 for K2O respectively. The per cent contribution from organic manure (FYM @ 10 t/ha) was 8.01, 4.75 and 2.47 for N, P2O5 and K2O nutrients. The response yard stick (kg output/kg input) was found to be 4.15 based on the targeted yield coefficients. The requirements of chemical fertilizers were reduced to 10 to 15% when organic manure (FYM @ 10 t/ha) was used along with chemical fertilizers for achieving targeted yield of (30 and 35 t/ha) of tomato grain respectively. The fertilizer targeted/adjustment equations and ready reckoners for interpolating optimum fertilizer doses at varying soil test values for attaining yield targets of 30 and 35 t/ha of tomato grain yield have been developed.
