Reaction of Highland Maize Inbred Lines Against Turcicum Leaf Blight (<i>Exserohilum turcicum</i>) Disease Under Artificial Inoculation

Maize is one of the most extensively grown crops in Ethiopia and the rest of the world. However, the maize production in Ethiopia is mainly threatened by the major foliar diseases like turcicum leaf blight (TLB), which cause up to 62.4% yield loss. To develop TLB-resistant maize varieties, it is important to look for resistant inbred lines. Therefore, the objective of this study was to evaluate the reaction of the highland maize inbred lines against TLB disease under artificial inoculation. Eighty inbred lines were obtained from the highland maize breeding program based at Ambo Agricultural Research Center (AARC). The experiment was arranged in a row-column design with two replications. The experiment was established at the AARC TLB screening maize pathology dedicated disease nursery field in the 2022 maize cropping season. The inbred lines were artificially inoculated using TLB disease inoculum. A scale of 0 to 9 was used to score, and the TLB disease severity was recorded four times at ten-day intervals starting from the disease onset. Disease data were analyzed using R-software version 4.0.5. The severity of the TLB disease was significant among the inbred lines. Accordingly, out of 80 genotypes screened for TLB Inbred lines coded as IL1-IL4 were resistant whereas IL5-IL22 were selected as moderately resistant.