Effect of integrated organic input management on resource use efficiency in maize -wheat cropping systems in sloping lands of the north-west Himalayas

Organic farming in the rainfed hill and mountain agriculture in the recent years has been given great emphasis due to its high prospects for enhancing sustainable crop productivity and resource conservation. A field experiment was conducted for four years (2007–08 to 2010–11) at Central Soil and Water Conservation Research and Training Institute, Research Farm, Selakui, Dehradun, Uttarakhand on a land having gentle slope (2%) to study the effect of integrated organic input (minimum tillage, organic amendments, vegetative barriers and weed mulch) management on yield, water conservation, erosion control, nutrient cycling, and economics in maize (Zea mays L.) - wheat (Triticum aestivum L.) cropping system. Wheat equivalent yield increased by 9.0% in treatment (T₄) which received 03 organic sources + minimum tillage (MT) + 3 times weed mulches + palmarosa as vegetative barrier compared to inorganic sources + conventional tillage (CT) + panicum as vegetative barriers (T₁). Four years average data showed reduction in run off and soil loss by 44.8 and 36.8%, respectively in T₄ treatment compared to inorganic treatment (T₁). The dry biomass yield of vegetative barriers varied from 4.85 to 9.95 q ha⁻¹ in different treatments and panicum gave higher biomass than palmarosa. On an average, T₄ treatment conserved soil moisture to the extent of 6.13 to 58.3 mm for wheat crop compared to inorganic treatments (T1) with the reduction of micro aggregates by 8–9% which increased basic infiltration rate and water use efficiency (WUE). The nutrient use efficiency (NUE) of all major nutrients (NPK) increased by 40.9% in T₄ treatment compared to T₁ treatment. The deep percolation loss of nutrient as determined by nutrient balance equation showed that maximum loss was incurred in T₁ (103 kg ha⁻¹) and minimum in T₄ (11.0 kg ha⁻¹). Though resource conservation was higher in organic treatment but organic farming was not found profitable in the initial years as net profit is decreased by 13.0% in T₄ treatment compared to T₁ after four years of cropping. Organic input management system requires higher premium price for farmer's acceptance in short term switching over (lag over) period and can bring more monetary return by adopting soil conservation measures through organic input management.