Comparable effect of commercial composts on chemical properties of sandy clay loam soil and accumulation of trace elements in soil-plant system

Plant growth in coarse texture soils is normally limited by plant-available nutrients. Organic amendments such as composts can improve soil properties for adequate plant growth. A pot experiment was conducted to evaluate the impact of commercial composts on soil properties and trace elements accumulation in soil-pant system. The treatments included; Green Force Compost (GFC), Super Bloom Compost (SBC), Lahore Compost (LCC) and University of Agriculture Faisalabad Compost (UAC) applied at rate of 5 g kg^-1 (0.5% w/w) and 10 g kg^-1 (1.0% w/w) of soil. Compost application altered the soil chemical properties like pHs of soils was decreased with all treatments, while electrical conductivity (EC) and soil organic matter (SOM) content were significantly increased. Highest increment in total nitrogen (TN), total potassium (TK) and SOM was 97, 38 and 33% with SBC (1.0%) than control, while the highest increase in total phosphorus (TP) was observed 69% with LCC at 1.0% than control. The concentration of cadmium (Cd) in grains of rice amended with GFC, LCC and UAC was found above safe limit. Concentration of Cd, copper (Cu), lead (Pb) and zinc (Zn) did not exceed safe limits only with SBC at 0.5%. The highest straw (36.69 mg kg^-1) and grain (23.84 mg kg^-1) yields were recorded with SBC (1.0%) which was 39 and 59% higher than control treatment where only chemical fertilizer (CF) applied. Despite significant increase in crop yield with SBC at 1.0%, this level cannot be recommended because of increase in the concentration of Cd above the critical limit. Therefore, SBC at 0.5% is recommended for sandy clay loam soil to improve soil fertility status and produce rice free of Cd and other metals.