Evaluation of blended fertilizer on growth performance and yield of onion (Allium cepa L.) at irrigated conditions Tselemti District North Western Tigray, Ethiopia

Onion has economically important crop in the study area. However, its low production is due to poor soil fertility management. Thus, the present study was initiated to determine the optimal rate of blended fertilizer required for onion production. A field experiment was conducted for two consecutive years during 2018 and 2019 at farmer's field Tselemti district, the experiment had 8 treatments arranged in a randomized complete block design with three replications. The treatments were 7 levels of NPSB (25, 50, 100, 150, 200, 250 and 300 kg  ha-1), recommended rate of N and P (105 N and 92 P2O5 kg ha-1), and a basal application of top dress N at rate of 69 kg ha-1 were applied for except the plot received recommended NP. The study results showed the application of blended fertilizer not significantly affected most of the crop parameters tested. However, they had a numerical difference among the treatments; since the highest (41157 kg ha-1) and lowest (32650 kg ha-1) marketable yields were obtained from a plot treated by 250 kg ha-1 plus a basal application of top dress N at rate of 69 kg ha-1 and from plots that received 50 kg ha-1 plus a basal application of top dress N at rate of 69 kg ha-1, respectively. Therefore, experiment for onion production should carry out on omitting trial of blended fertilizer in the study area.  Key words: Blended fertilizer, onion, omitting trail, recommended NP.