Effect of In situ Recycling of Sugarcane Crop Residues on Soil Enzyme Activities Under Soybean–Maize System

Abstract

An investigation was carried out by conducting a field experiment at the farm of the Mahatma Phule Krishi Vidyapeeth (MPKV), Rahuri. The significant grain yield of soybean (37.5 q ha−1) and maize (49 q ha−1) were observed in the treatment receiving 100 % recommended doses of Nitrogen, Phosphorus and Potassium (NPK) + in situ compost of crop residues, pressmud compost (T6). After harvest of maize dehydrogenase activity, acid phosphatase, β-glucosidase and urease were significantly improved in T7 treatment as compared to other treatments. However, fluorescein diacetate activity and alkaline phosphatase were significantly greater in T6 treatment in post-harvest soil samples of maize. In the post-harvest soil of maize the bacterial and actinomycetes population were greater in the treatment receiving in situ decomposition of sugarcane crop residues + 100 % recommended dose of NPK (T3). The fungal population after harvest of maize was found maximum in treatment T7. The total organic carbon was significantly correlated with dehydrogenase (r = 0.65, P < 0.01), fluorescein diacetate (r = 0.71, P < 0.01), acid phosphatase (r = 0.66, P < 0.01), β-glucosidase (r = 0.65, P < 0.01), and urease (r = 0.57, P < 0.01). There was a significant correlation (r = 0.77, P < 0.01) between TOC and soybean yield, and between total organic carbon and maize yield (r = 0.98, P < 0.01). The result suggest that in situ recycling of sugarcane crop residues and the industrial wastes with suitable interventions like use of bioinoculum, phosphatic fertilizer and urea may help for improving better crop productivity and soil biological activities.