Effect of spent Mushroom composts and Inorganic fertilizers on the yield of and nutrient uptake by wheat

A screen-house experiment was undertaken to test if spent mushroom compost (SMC) could be used as an organic manure for wheat in a sandy loam soil. The treatments consisted of three types of organic amendments [white button spent mushroom compost (WB-SMC), Oyster spent mushroom compost (OY-SMC) and farmyard manure (FYM)] applied @ 0.75% on soil weight basis and four levels of inorganic fertilizers (0, 50, 75 and 100% of recommended dose of chemical fertilizers) in all possible combinations. The experiment was laid out in a completely randomized factorial design with three replications. A control without any organic amendment and inorganic fertilizers was also included in this study. The recommended dose of N, P and K chemical fertilizers (RDCF) was taken as 150, 26 and 50 mg kg⁻¹ soil, respectively. Yields (grain and straw) and uptake of N, P and K of wheat crop were highest in the treatment receiving WB-SMC + 100% RDCF. However, with OY-SMC + 100% RDCF treatment, yields and uptake of N, P and K were even lower than the treatment receiving only 100% RDCF fertilizer. The mean dry matter yields and uptake of nutrients (grain and straw) confirmed the supremacy of WB-SMC over other organic amendments including FYM. In the absence of inorganic fertilizers, organic amendments increased dry matter yields as well as nutrient uptake over control; nevertheless, an exception to this was OY-SMC treatment where the yields and uptake of N, P and K decreased drastically compared to control. The WB-SMC + 75% of RDCF treatment produced grain yield equivalent to that obtained with 100% RDCF alone.