Susceptibility to lodging is a major constraint on teff production in Ethiopia, but efforts to develop lodging-resistant cultivars have not been successful. We studied the mechanical properties of teff culms and associated agro-morphological traits in field experiments with 320 teff accessions at two sites in northwestern Ethiopia during the 2018 and 2019 growing seasons. The results showed significant variability in both mechanical properties and agro-morphological traits among accessions. Traits contributing to lodging resistance, such as internode diameter, pushing resistance, and base failure moment, were significantly positively correlated with each other and with plant height. Similarly, the correlation of those traits with lodging index was significant and positive. In contrast, tiller number showed a significant negative correlation with lodging index. The peduncle–panicle length, which generally accounted for 59% of the plant height, should be a target when breeding for semi-dwarfism. Root system development, which reached a depth of more than 1 m in tall and 57 cm in dwarf teff accessions, signifies the presence of genetic variabilities for future root lodging studies in teff, and it may also explain why teff performs well in drought-prone areas of Ethiopia. Breeding programs for lodging resistance might focus on accessions with good standing ability (high base failure moment) and introgression of stem strength with a semi-dwarf phenotype. Alternatively, selection for a large internode diameter, increased pushing resistance and base failure moment, and a reduced tiller number should be considered.

Teff is the most strategic cereal crop grown from high rainfall to drought prone areas of Ethiopia, where it covers nearly 30% of the land allotted for cereals. However, its productivity remains very low due to lack of knowledge and research interventions. To investigate the grain yield potential, estimate the genetic parameters, and the diversity, a pot experiment with intensive management and a field experiment with conventional management at two contrasting locations for two seasons using the same 317 genotypes and additional 3 improved cultivars in the field experiment were carried out. The results showed highly significant variation among the genotypes for grain yield, biomass, harvest index, and phenological traits under both experiments. The best linear unbiased predictor (BLUP)-adjusted grain yield performance of the genotypes ranged from 4.2 to 8.8 g/plant in the intensive management and 1.8 to 4.3 g/plant in the field growing condition with conventional management. Coefficient of genetic variation, heritability, and expected genetic advance for grain yield were the highest in both experiments. Among the phenological traits, the grain filling period in the intensive growing condition exceptionally showed the highest genetic coefficient of variation and genetic advance. The high grain yield performance and wider range of the harvest index observed under the intensive management condition with moderate to high heritability signifies the genetic potential of teff for further improvement through trait recombination.

Waterlogging stress, particularly during flowering, severely constrains wheat production, yet the optimal timing and frequency of waterlogging priming and its linkage to post-stress nitrogen acquisition remain unclear. We conducted pot experiments under a glasshouse over two consecutive growing seasons (2022/23 and 2023/24) using the Japanese bread wheat cultivar Norin 61. Eight treatment combinations were established with or without waterlogging priming applied at the tillering, stem elongation, and booting stages, followed by waterlogging for 5 days (2022/23) and 4 days (2023/24) during the flowering stage. To quantify post-stress nitrogen dynamics, ¹⁵N-labeled ammonium sulfate was applied immediately after waterlogging termination at flowering, and ¹⁵N uptake and its allocation to plant organs and grains were determined during grain filling and at harvest. Compared to the non-primed treatment, treatments that included tillering-stage priming consistently maintained higher leaf SPAD values, photosynthetic performance, and increased thousand-grain weight across both seasons, and grain yield increased by 54.8–80.6% in 2022/23 and 125.8–159.7% in 2023/24. These treatments also showed higher post-stress ¹⁵N content and greater ¹⁵N allocation to grains. Overall, tillering-stage waterlogging priming was associated with improved tolerance to flowering-stage waterlogging in wheat through the maintenance of post-stress nitrogen uptake capacity and nitrogen allocation to grains.

Waterlogging stress, particularly during flowering severely constrains wheat production, yet the optimal timing and frequency of waterlogging stress memory and its linkage to post-stress nitrogen acquisition remain unclear. We conducted pot experiments under glasshouse over two consecutive growing seasons (2022/23 and 2023/24) using the Japanese bread wheat cultivar Norin 61 to evaluate eight treatment combinations of waterlogging stress memory applied at the tillering, stem elongation, and booting stages, followed by waterlogging during flowering stage. Leaf greenness (SPAD), chlorophyll fluorescence (Fv′/Fm′), photosynthetic rate, yield and its components, and nitrogen dynamics were assessed. To quantify post-stress nitrogen uptake, ¹⁵N-labeled ammonium sulfate was applied immediately after waterlogging termination at flowering, and ¹⁵N uptake and allocation to plant organs and grains were determined during grain filling and at harvest. Treatments that included tillering-stage stress memory consistently delayed leaf senescence, maintained higher photosynthetic performance, increased thousand-grain weight, and improved grain yield relative to the non-primed treatment, with reproducible effects across both seasons. These treatments also showed higher post-stress ¹⁵N uptake and greater ¹⁵N allocation to grains. Overall, tillering-stage waterlogging stress memory was associated with improved tolerance to flowering-stage waterlogging in wheat through maintenance of post-stress nitrogen uptake capacity and nitrogen allocation to grains.