Effect of Septoria tritici blotch (Zymoseptoria tritici) on yield and yield components of bread wheat (Triticum aestivum L.) in Holeta, Ethiopia

Abstract

Abstract Septoria tritici blotch is one of the most important yield-limiting diseases of wheat in Ethiopia. Yield loss assessment was conducted in a Randomized Complete Block Design with three replications at the Holeta Agricultural Research Center experimental field during the main cropping season of 2022/2023. The experiment was conducted to determine the integration effect of wheat variety, fungicide, and planting date on the grain yield of bread wheat. Evaluation was started from the onset of the disease 63 days after planting. The effects of Septoria tritici blotch on grain yield were significant (P < 0.05) when the two varieties Alidoro and Pavon − 76 planted on July 10th and treated with fungicide at a rate of 0.75 l/ha, produced the highest yields of grain (6.4and 5.7 ton/ha respectively). Results also showed that the highest yield losses (64.1 and 50.0%) were computed on untreated control plots of the cultivars Pavon 76 and Alidoro respectively, which were planted on 10th July and 1st July, compared with maximum protected experimental treatment for both cultivars. Furthermore, data on cost-benefit analysis showed that Alidoro treated with 0.75l/ha fungicide rate had the highest net benefit of 340330 B/ha and the highest marginal rate of return of 6714.29%. Pavon − 76 treated with 0.75l/ha fungicide rate and planted on 10th July came in second with a net benefit of 301830 B/ha and a marginal rate of return of 5253.98%. Disease parameters like disease severity and the area under disease progress curves were negatively correlated with yield and yield components, whereas, yield components were positively correlated with yield. The farming communities should be trained or advised on the timely application of efficient fungicides against septoria trititci blotch which may lead to the utilization of an integrated disease management strategy.