1Chief Agronomist, Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
2Junior Soil Scientist, Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
3Junior Agronomist (Onstation), Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
4Junior Economist, Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
5Junior Agronomist (On-farm), Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
6Senior Research Fallow (Fishery), Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
7Senior Research Fallow (Veterinary), Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
8Associate Professor, Department of Agricultural Economics and Farm Management, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
9Ph. D. Scholar, Integrated Farming System, Assam Agricultural University, Jorhat, Asom, 785 013
Assam Agricultural University, Jorhat, Asom, 785 013
*Corresponding author Email: baishya.ajit@gmail.com
Online published on 15 February, 2016.
The long-term effects of inorganic alone and combine effect of inorganic as well as organic sources of nutrients on soil fertility and crop productivity were investigated in rice (Oryza sativa L.)-rice cropping sequence in acid soils of north-east India from 1987 to 2014. The higher average grain (6.50 t/ha) and straw (8.25 t/ha) yields of the rice-rice sequence were recorded in case of 75% recommended nitrogen, phosphorus, and potassium (NPK) through fertilizers along with 25%N through incorporation of crop stubbles in winter rice at the time of puddling and 75% recommended NPK through fertilizers in autumn rice. The higher available N, P and K status of soil were recorded when recommended 50% NPK through chemical fertilizers applied along with 50%N through Azolla in winter rice and 100% recommended dose of NPK through chemical fertilizers to autumn rice. However, uptake of NPK by rice-rice sequence was higher when 75% recommended NPK dose was applied through chemical fertilizers to both winter and autumn rice along with 25%N through crop stubbles only in case of winter rice. Thus, integrated nutrient management involving organic and inorganic sources not only increases the availability and uptake of major nutrients but also helps in yield sustainability in rice-rice cropping system under long run in acid soils.
Integrated nutrient management, Long-term cropping system, NPK uptake, Physico-chemical properties of soil, Rice-rice cropping system
