Changes in soil biological and chemical environment during wheat growth stages under nitrogen and straw management practices in rice-wheat system

Abstract

Crop residues are a neglected source of sustainable agriculture since they are produced in large quantities, yet farmers frequently burn them. The purpose of this study was to assess the effects of nitrogen (N) application rate and residue management strategies for wheat production on changes in soil enzyme activity, microbial count, and chemical properties at various growth stages. Different combinations of N fertilizer rates, tillage, and residue management practices for wheat were investigated in split-plot design. The main plots were assigned for two N applications rates (N75 and N100, 75 and 100% recommended dose of N, whereas the subplots were assigned for seven treatments as: (1) conventional tillage (CT)-rice residue removed (R), (2) sowing with rotoseeder (RS)-R, (3) sowing with Happy Seeder (HS)+ loose rice residue removed (R50), (4) HS + 100% rice residue retained (R100), (5) RS + R50, (6) RS + R100, (7) CT + R100. The results revealed that N100 and HS + R100 increased wheat yield, chemical and biochemical properties, with the exception of polyphenol oxidase and peroxidase. All biochemical characteristics were greater during vegetative and reproductive growth stages than before seeding and harvesting. Dehydrogenase, polyphenol oxidase, and flourescein diacetate were found as the most sensitive indicators using principle component analysis.