| economy of fertilizer nitrogen through organic sources in rain-fed rice-legume cropping systems in west bengal, india. | field experiments were conducted at a farmers" plot adjacent to the regional research station, red and laterite zone, sub-center sekhampur (birbhum district) of west bengal, india, situated 23 degrees 24' n latitude, 87 degrees 24' e longitude, to study the effect of different bio- and organic sources of nutrients instead of total fertilizer n in terms of crop productivity in the sequence and building up of soil fertility. during the wet seasons of 1997 and 1998, 12 combinations of bio- and orga ... | 2001 | 12805756 |