Department of Genetics and Plant Breeding, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, 221005.
1Present address: Department of Forestry, Guru Ghasidas University, Bilaspur, M,P., 495009.
The dynamics of nitrification and net N-mineralization during upland rice (Oryza sativa) and lentil (Lens culinaris Medic.) cultivation in tropical dryland farming system, were studied. Mineral N (ammonium-N and nitrate-N) content was higher under lentil than under rice cultivation while nitrification and net N-mineralization were more during rice (wet period) than lentil growth (dry period). All the parameters increased due to the amendment with NPK fertilizers, farmyard manure or both. Application of NPK fertilizer together with farmyard manure are more advantageous than of NPK alone from nitrogen supply point of view. Climatic variables temperature and rainfall, and soil water appeared to be not very much important in determining the nitrogen mineralization in highly impoverished dryland tropical arable soils.
Nitrogen mineralization, nitrification, nitrogen availability, dryland farming, upland rice, lentil
