Effect of nitrogen, farmyard manure and non-symbiotic nitrogen-fixing bacteria on yield, nutrient uptake and soil fertility in upland rice (Oryza sativa)

Abstract

A field experiment was conducted during 2001-03 to study the effect of N (0,30 and 60 kg/ha), farmyard manure (0 and 5 tonneslha) and seed inoculation with diazotrophs (Azotobacter chroococcurl7 and Azospirillunz brasilense) on yield, nutrient uptake by upland rice (Ogea sativa L.) and residual build up of various forms of N in an acidic Alfisol. The yield, N, P and K uptake by paddy and various forms of N in soil increased significantly with applied N, farmyard manure and nitrogen-fixing bacteria. The effect of Azotobacter was more prominent than Azospirillunt for above properties and the inoculation with Azotobacter and Azospirillunz increased the grain yield by 15.9 and 9.1 %respectively over non-inoculated yield. The interaction effect of N, farmyard manure and biofertilizer was significant. A combined dose of 60 kg N, 5 tonnes farmyard manure and seed inoculation with Azotobacter was most suitable for the upland paddy production (3.9 tonneslha) with adequate nitrogen build up in Alfisol of Meghalaya.