Response of Durum Wheat (Triticum durum L.) Genotypes to Blended NPSB Fertilizer Rates and Wheat Rust Diseases in Southern Ethiopia

Lack of improved varieties and soil fertility degradation are among the major factors that limit durum wheat (Triticum turgidum L.) production in Ethiopia. The objectives of this study were to determine the response of durum wheat cultivars (i) to nitrogen, phosphorus, sulphur, and boron (NPSB) fertilizer blend; (ii) rust infection; and (iii) partial budget analysis using NPSB fertilizer blend. A 2-location experiment was conducted in 2021 in South Ethiopia to evaluate the response of 4 durum wheat genotypes to blended NPSB fertilizer rates in a randomized complete block design in a 4 × 4 factorial arrangement. The results showed significant (P<0.05) differences due to genotypes (G), rate of NPSB fertilizer (F), and location (E) for all the parameters. The effects due to the G × F × E interaction were significant (P<0.05) for the number of total tillers, number of productive tillers, and grain yield (GY). A significant (P<0.05) G × E interaction was observed for the majority of parameters except days to 50% heading and plant height. Durum wheat genotype S3-213037 produced the highest grain yield of 3689.3 kg·ha−1 when NPSB fertilizer was applied at a rate of 225 kg·ha−1 at Adekoysha. Moreover, partial budget analysis indicated that genotype S3-213037 accrued a maximum benefit of 112,986.50 birr·ha−1 and the highest marginal rate of return of 1356.4% when NPSB fertilizer was applied at a rate of 225 kg·ha−1. Therefore, this study indicated that the application of an NPSB fertilizer rate of 225 kg·ha−1 could be used in the production of durum wheat in the East African region with similar agroecologies to the study area.