Effect of water and nitrogen on performance and yield of rice under shallow water table condition
Abstract
An experiment was carried out to study the effect of different water regimes and nitrogen levels on growth pattern and yield of rice (Oryza sativa L) in a silty clay loam soil (Aquic hapludoll) associated with shallow water tables during kharif 1999 at Floriculture Research Center, Patharchatta located in the campus of G.B.P.U.A.&T, Pantnagar, Uttaranchal. A split plot design with four replications was used with three water regimes (Wcf=continuous flooding of 5cm; W&= flooding to saturation; Wrf= Rainfed) as main plots treatments and four nitrogen levels (N0=OkgN/ha; N60=60 kgN/ha; Ni20=120 kgN/ha; N180=180 kgN/ha) as subplots treatments. The water table fluctuated between 0.0m – 0.35m depths from the surface during rice growing season. Results revealed that the rainfed treatment receiving 180kgN/ha had better crop growth and nitrogen uptake as compared to the other treatments. Higher tillers no., plant height, dry matter production, leaf area index, spikelets/m, panicle/m were recorded under rainfed condition receiving ISOkgN/ha.Grain yield of rice across water regimes was significantly higher (61.22q/ha) in rainfed treatment followed by flooding to saturation (57.95q/ha) and continuous flooding (57.25q/ha). Similarly, highest grain yield of 70.60q/ha was attained with an application of 180 kg N/ha. The lowest yield (44.12q/ha) was recorded in the control plot. Rainfed treatment was found to be the most economic with BC raioo 2.05i comparison to flooding to saturation (Wfs) and continuous flooding.(Wcf). Among the nitrogen treatment the highest B: C ratio was observed in the N180 kg/ha (2.17) followed by N120, N60kg/ha. The lowest B; C ratio was observed in the N Okg/ha (1.28) The experimental findings of present study indicated that in the shallow water table conditions higher yield can be obtained under rainfed conditions, thereby, increasing the water use as well as nitrogen use efficiency in rice.
