Evaluation of Ethiopian Bread Wheat (Triticum Aestivum L.) Genotypes Against Leaf Rust (Puccinia Triticina)

Leaf rust caused by Puccinia triticina is a serious threat to wheat production in Ethiopia. A study was carried out to detect physiological races of the pathogen from the East Shewa zone and identify leaf rust resistance genes in Ethiopian bread wheat genotypes and cultivars at the Debrezeit Research Center, a hot spot for leaf rust. In a field experiment, 91 bread wheat genotypes along with nine susceptible checks (Alidoro, Dandaa, Digelu, Enkoy, Hidase, Kingberd, Kubsa, Ogolcho, and Wane) were evaluated against leaf rust at Debere Zeit during the 2021/22 main season. Final Rust Severity (FRS), Area Under Disease Progress Curve (AUDPC), and Coefficient of Infection (CI) were used to measure leaf rust resistance in the test materials. Analysis for all disease parameters, including correlation analysis, was carried out using SAS software. There were highly significant differences (P<0.01) for all disease parameters among the test genotypes. Of the tested genotypes, 51 exhibited low rAUDPC, CI, and FRS with the MR infection type. These genotypes had FRS ranging from 31 to 50%, CI values ranging from 21 to 40, and rAUDPC between 31 and 70% and were regarded as moderately slow rusting resistance genotypes. They showed moderate resistance to adult plant resistance in field conditions. Therefore, these genotypes can be used as a source of resistance in wheat leaf rust resistance breeding. Moreover, additional bread wheat genotypes should be evaluated in the next study for prevailing leaf rust races both at seedling and adult plant resistance.