Soil Microbial Properties as Affected by Short-Term Contrasting Tillages and Cropping Systems in a Rainfed Agro-Ecosystem of Northern Odisha

摘要

Conservation agriculture (CA) has been proposed as a portential system for improving soil organic matter and microbial attributes in the rainfed agro-ecosystem under the hilly tracts of North Odisha and the impact was assessed after 3rd cropping cycle. The treatments comprised of conventional tillage (CT) and minimum tillage (MT) with sole maize (M) and inter crop maize + cowpea (M+C) in main-plots during wet season and horsegram (H), Toria mustard (T) and no cover crop (NCC) in sub-plots during dryseason. Residue buildup and reduced soil disturbance in MT elevated the SOC (+27.9%, + 15.2%, MBC (+ 115.1%, + 66.5%), population of bacteria (+61.2%, +23.0%), fungi (+36.8%, +28.2%) and actinomycetes (+34.6%, +25.3%) over the initial status in the layers of 0—5 and 5—10 cm. The microbial quotient in MT soils (2.03%) was more than CT soils (1.53%) and solis under cover crops (1.83%) was higher than that of NCC (1.68%) in the surface layers (0—5 cm). The metabolic quotient in soils under MT was 37.9 and 21.4% lower than the soils under CT in top two layers indicating more efficient microbial community in MT soils. These soil microbial properties wereshown to be sensitive indicators of long-term tillage management under rainfed agro-ecosystem.