Trade-off with tillage, irrigation schedules and novel rice establishment methods implications on soil properties and plant biomass nitrogen chemistry

Abstract

Global food security depends on the continued success of rice production. Though rice production has shown a consistent increase, it faces major challenges: The increasing demand for rice versus declining growth in yield and harvested area; soil fertility and productivity decline of intensive rice-based cropping systems resulted from depletion and or limitations of natural resources (soil and water) for rice production. Therefore a field study was conducted for three seasons on a clay loam soil in karnataka, India during Kharif season (2015 & 2016), Rabi season (2015) to investigate the trade-off with tillage, irrigation schedules and novel rice establishment methods implications on soil properties and plant biomass chemistry. Tillage treatments were Dry (No puddling) and wet tillage (puddling), Establishment methods were Direct seeding (DSR, WSR) and Transplanting (NPTR, PTR), Irrigation treatments were based on soil water tension (SWT) ranging from continuous flooding/saturation (daily irrigation) to alternate wetting and drying (AWD) with irrigation thresholds of 10 and 40 kPa at 18-20cm soil depth. The study reveals that among different establishment methods DSR and NPTR under dry tillage (non puddle) condition recorded higher available N, P and K (kg/ha). Higher Organic carbon (g/kg), low bulk density, less textural disturbance compared to WSR and PTR under wet tillage (puddled) conditions.