Response of an Up-Land Rice (NERICA-4) Varietyfor Row SpacingandNitrogen FertilizerRate in Pawe Area, North western Ethiopia

Abstract

An experiment was conducted at Pawe research station and on farmers field in two cropping seasons (2016 and2018), to investigate the effect of row spacing(RS) and nitrogen (N) fertilizer rate on yield and yield component and to determine economically optimum row spacing and N fertilizer rate for an upland rice variety (NERICA-4). The experiment had three row spacing(20, 25 &30 cm) and four N-rates (0, 32, 64 and 96 k ha^-1) totally twelve treatments.It was laid out in RCBD with factorial arrangement andthree replications. Analysis of variance was highly significant (P<0.001) difference due to treatment effect for 90% physiological maturity, plant height, No of tiller per 0.5m row length, Aboveground biomass yield (BY), Grain yield (AGY) and Thousand kernels weight. The highest BY (9677 kg ha^-1) was produced by 20 cm RS with application of 96 kg N ha^-1,but at par with 25 and 30 cm row spacing and 96 kg N ha^-1.The highest AGY (4704.6 kg ha^-1) was produced by RS of 20 cm and 96 kg N ha^-1. But, it was at par with of 25 and 30 cm row spacing with application of 96 kg N ha^-1. The marginal rates of return(MARR) 295.95 % was the optimum profitable rate in the current finding, because it was well above MARR, 100% and produced an additional mean seed yield advantage of 194.12% over control. Hence, the economic analysis suggests that marginal benefits of rice would be higher, if fertilizer and row spacing is used at 30 cm row spacing and a rate of 96 kg N ha^-1, because it gave the highest net benefit, 28358.68 EB/ha.