Variability among Ethiopian durum wheat genotypes grown under different climatic conditions of Tigray for some agronomic and grain-quality traits

The lack of adaptable varieties is the major problem for durum wheat (Triticum turgidumvar.durum) production in Ethiopia. The variability in 36 durum wheat genotypes was studied for key traits across locations to select genotypes possessing optimal grain quality and high grain yield for production in northern Ethiopia, using a simple lattice design. Variation attributable to genotypes (G), locations (L) and G x L interaction was significant for the studied traits (p < 0.001). Mean grain protein content (GPC) among genotypes ranged from 9.4% to 12.9%. Genotypes 208312 (G17) and 208168 (G22) had mean GPC of 12.9% and 12.8%, respectively. Grain with high GPC (12.7%-21.3%) was harvested from Beati-Maymesanu (BMM), a terminal drought-affected location, whereas the lowest GPC range (5.5%-10.5%) was recorded at Agarba. This implied that water stress during the reproductive growth stage of durum wheat could increase GPC. Similarly, high gluten index (GI) (68%-95%) was obtained at BMM, whereas the frequency of genotypes with low GI (<60%) was high (n = 14) at Agarba. Genotypes with higher GPC and GI tended to have lower grain yield (GY). This negative association constrains breeding efforts to combine high GY with high GPC and GI. However, some genotypes, mainly farmers' varieties (FVs), had combined high GY with the modest value of GPC and GI. FVs SSD2, 248478, 222426, and 208873 and the improved varietiesAsassaand Quamy were suitable as parents for making crosses to generate new genotypes with high GY, GPC, and GI.