EFFECT OF PRECEDING CROP AT DIFFERENT DOSES OF FERTILIZER ON PRODUCTIVITY, NUTRIENT UTILIZATION AND FERTILIZER-USE EFFICIENCY OF WET-SEASONRICE (ORYZA-SATIVA)

An investigation was carried out during 1990-92 at Mohanpur, eo assess the effect of preceding crop at different doses of fertilizer on prod uctivity, nutrient utilization End fertilizer-use efficiency of wet-se ason rice (Oryza sativa L.). Fertilizer application at 100% of the rec ommended dose resulted higher net economic return in rice (Oryza sativ a L.)-wheat (Triticum aestivum L. emend. Fiori & Paol.) and rice-India n mustard [Brassica juncea (L.) Czernj & Cosson] sequences but in rice -groundnut (Arachis hqpogaea L.) sequence that was at 125% dose, altho ugh the difference between 100% and 125% dose was not statistically si gnificant. Higher grain yield of wet-season rice was obtained after gr oundnut, followed by Indian mustard and wheat in sequence, Uptake of N , P and K was higher in 100% dose than 75% and 125% of recommended dos e in all the sequences. Fertilizer-use efficiency and agronomic effici ency were higher in rice-groundnut:sequence than under other sequences .