Abstract
A field experiment was conducted in the Lemo and Misha districts of Central Ethiopia to evaluate the response of bread wheat (
Triticum aestivum
L.) varieties to the integrated application of NPSB and urea fertilizers on grain quality and nitrogen concentration under acidic soil conditions. The experiment was arranged in a split–split plot design comprising two varieties (Wane and Bondena), three NPSB fertilizer rates (0, 100, and 150 kg·ha
−1
), and three urea rates (0, 150, and 200 kg·ha
−1
). The combined use of fertilizers significantly affected grain quality traits and nitrogen concentration in grain and straw. The lowest hectoliter weight (57.99 kg·hL
−1
) was recorded in the unfertilized control treatment, while the highest value (81.36 kg·hL
−1
) was achieved with the combined application of 200 kg·ha
−1
urea and 150 kg·ha
−1
NPSB, representing a 40.3% increase over the control. A similar pattern was recorded for nitrogen content: The same unfertilized treatment gave the lowest concentrations in grain and straw (1.20% and 0.21%, respectively), while the highest values (2.04% and 1.75%) were obtained from 200 kg·ha
−1
urea plus 100 kg·ha
−1
NPSB. Overall, the findings indicate that the integrated application of urea and NPSB fertilizers significantly improved wheat grain quality and nitrogen concentration under acidic soil conditions. Therefore, balanced fertilizer management represents an effective agronomic strategy for enhancing bread wheat grain quality and nitrogen concentration in the highlands of Central Ethiopia.