Status and evaluation of released bread wheat varieties-fungicide interactions against the major rusts in the Western Hararghe Highlands

Abstract

Bread wheat is a crucial crop that feeds billions of people worldwide. However, it is often affected by various stresses, including, wheat rust which can hinder its production and productivity. To evaluate the severity of this issue and the effectiveness of various treatments, a study was conducted in West Hararghe during the 2020 main cropping season. The survey covered a total of 125 cultivated fields, each of which was assessed for wheat rust prevalence. Four fungicides, including the unsprayed plot and five bread wheat varieties, were used as a
treatment. The experiment was laid out in RCBD with three replicated plots. Among those fields, the disease was prevalent in 125 (100%) fields. Major wheat rust severity varies across locations. The maximum disease severity (22.5%) was recorded in the Gemechis district, while the lowest disease severity (11.0%) was recorded in the Tulo district. An incidence of 85.0% in the Gemechis and 61.5% in the Tulo districts were recorded. The effects of different fungicide interactions on wheat rust epidemics and the yield of bread wheat varying in reaction to the
disease were studied in the major wheat growing district (Gemechis) of West Hararghe, Ethiopia. Generally, stripe, leaf, and stem rusts started to be observed from tillering to late after an ear head emergence. Fungicide spray treatments significantly reduced wheat rusts. Test fungicides revealed a comparable and better level of efficacy on wheat rust disease severity reduction compared to the unsprayed check. Thousand kernel weight reductions of up to 32.3% and 24.6% at Gemechis were recorded. Generally, Danda’a with Jeba and Shorima with
progressive fungicide application provided better control of bread wheat rusts.