Screening of Finger Millet Genotypes for Resistance to Magnaporthe grisea in Northwestern Ethiopia

Abstract

Finger millet is one of the staple cereal crops cultivated in Ethiopia. However, its production is challenged by blast disease. This study aimed to screen finger millet genotypes for resistance to blast under natural epiphytotic conditions and to assess the yield potential of resistant genotypes during the 2022 and 2023 main cropping seasons. A total of 64 finger millet genotypes, including both standard and local checks, were evaluated using a square lattice design with two replications at the Adet and Finote Selam experimental sites. Disease severity was scored from the initial onset using a 0–9 rating scale for leaves and a 0–5 scale for necks and heads. At Adet in 2022, 13 genotypes (20.31%) were resistant, 4 (6.25%) moderately resistant, 17 (26.56%) moderately susceptible, and 30 (46.88%) susceptible. In 2023, 14 genotypes (21.88%) were resistant, 11 (17.19%) moderately resistant, 24 (37.50%) moderately susceptible, and 15 (23.44%) susceptible. At Finote Selam in 2022, 3 genotypes (4.69%) were moderately resistant, 7 (10.94%) moderately susceptible, 32 (50.00%) susceptible, and 22 (34.38%) highly susceptible. In 2023, 2 genotypes (3.13%) were moderately resistant, 6 (9.38%) moderately susceptible, 38 (59.38%) susceptible, and 18 (28.13%) highly susceptible. The variation in genotype responses across locations and years can be attributed to differing ecological factors. Notably, genotypes G7 and G20 demonstrated high yield potential but were susceptible to blast, whereas G13 and G61 showed low terminal disease severity but lower yields. Crossing high-yielding susceptible genotypes with resistant low-yielding ones may offer an effective breeding strategy. Incorporating resistant and moderately resistant genotypes into cultivation and breeding programs can improve production, mitigate blast impact, and reduce farmers’ reliance on chemical fungicides, ultimately lowering production costs and minimizing environmental harm.