Seeding and blended nitrogen phosphorus sulphur and boron (npsb) fertilizer rate effect on yield and yield components of oat varieties (Avena sativa L.) at Chencha, South Ethiopia

Abstract

Oat is one of most important cereal crops mainly cultivated in highlands of Ethiopia. However, its production remains constrained due to limited varietal options, absence of site-specific recommendations for blended fertilizer application, and optimal seeding rates. Therefore, this study was conducted to determine the rate of seeding and blended NPSB fertilizer on yield and yield components of oat varieties during 2023/24 cropping season at Chencha, South Ethiopia. The study consisted three seeding rates combined with two oat varieties (main plot) and four levels of blended NPSB fertilizer (sub plot) laid out in split plot design in three replications. Data on crop phenology, growth, yield and yield components were collected and subjected to analysis of variance. The results showed that days to heading, days to maturity, plant height, biomass yield, grain yield, thousand seed weight and harvest index were significantly (p≤0.05) affected due to seeding rate combined with oat variety and blended NPSB fertilizer rates. The Souris variety proved superior, achieving the highest biomass (21,348.3 kg ha^-1) at a 100 kg ha^-1 seeding rate and the maximum grain yield (3,589.5 kg ha^-1) at the 130 kg ha^-1 rate. Separately, the optimal fertilizer level was 100 kg ha^-1 of blended NPSB, which produced the highest average biomass (15,994 kg ha^-1) and grain yield (2,344 kg ha^-1). Therefore, cultivating the Souris variety at a seeding rate of 100 kg ha⁻¹, coupled with the application of 100 kg ha⁻¹ of blended NPSB fertilizer, is recommended to achieve balanced and optimal oat production in Chencha and comparable agro-ecological zones.

Keywords: Blended fertilizer; Oat; Seeding rate; Soil fertility