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Wheat quality testing facilities in Ethiopia are limited. The aim of this study was to determine whether size‐exclusion high‐performance liquid chromatography (SE‐HPLC) could be used in breeding programs for quality testing. Thirteen Ethiopian and two South African wheat cultivars were evaluated in two diverse environments for milling and dough characteristics. SE‐HPLC was done on the same samples. Across environments, both SDS‐soluble and SDS‐insoluble polymeric proteins significantly influenced important quality characteristics such as SDS‐sedimentation and mixograph development time. The large monomeric proteins, which are mainly gliadins, had a consistently significantly negative effect on quality. The increase of polymeric protein as opposed to monomeric protein led to improvement of quality characteristics. The SDS‐soluble and SDS‐insoluble polymeric proteins were equally important in quality prediction. The amount of polymeric proteins was significantly higher in the high‐protein environment. Despite a large environmental effect on most fractions, a large ratio of polymeric proteins to monomeric proteins (both SDS‐soluble and SDS‐insoluble) can be a good indicator of baking quality. SE‐HPLC is therefore an option to use in breeding programs in Ethiopia for quality evaluation.

A study was conducted at Dabat, Northwestern Ethiopia, during 2010 cropping season. Genotypic and phenotypic coefficient of variation, heritability and correlation coefficients were performed for yield and its contributing parameters in 10 faba bean genotypes. Analysis of variance for traits studied showed significant (P<0.01) differences among the genotypes. Phenotypic coefficient of variation values for most characters was closer than the corresponding genotypic coefficient of variation values showing little environment effect on the expression of these characters. The estimated values of broad-sense heritability were found to be between 27 (stand count at emergence) and 81% (grain yield). Heritability values determined were 72, 67, 65, 46, 44, 53, 58 and 45% for 100 seed weight, biological yield, number of pods per plant, number of pods per node, disease status, days to flowering, days to maturity and plant height, respectively. High heritability indicated that selection based on mean would be successful in improving these traits. Positive and significant correlation coefficients were also obtained between number of pods per node and each of plant height (r = 0.676**), number of pods/plant (r = 0.636**) and number of nodes per plant (r = 0.421*). Pods per plant had a significant positive correlation with plant height (p<0.01) in this study.

Drought is a common abiotic stress in Ethiopian agriculture. Crop yield is at risk due to drought that happens at various developmental stages of the crop. This experiment evaluated 248 Ethiopian bread wheat genotypes under water stress and non-stress growing conditions. Augmented complete block design with three blocks and eight replicated entries was used. Analysis of variance showed significant diversity among the genotypes in reaction to water stress. The average root and shoot lengths were reduced by 33.4% and 28.8%, respectively, due to water stress. The average fresh biomass per plant was 192 mg for non-stressed and 116 mg for stressed treatments, suffering a 40.5% reduction due to stress. Accessions 8314, 204463, 204454 and 204521 showed the longest roots while accessions 222381, 222405, 222439 and 204586 showed the shortest roots under stress conditions. Drought tolerance indices were calculated based on root length. Geometric mean performance (GMP) index was found helpful in identifying the relatively stable genotypes across the two water regimes. High GMP indices were observed for genotypes 8314, 204521, 231614, and KSN81 which were long rooting genotypes under both stress and non-stress conditions. ANOVA based on region of collection showed that genotypes from Southern Nations Nationalities and Peoples Region had the longest roots. Elevation of origin did not show any significant difference for any of the traits measured. This study demonstrated the presence of large variations for water stress response in the Ethiopian bread wheat germplasm. The identified stress resistant genotypes can be used as potential breeding stocks to develop drought resistant cultivars.

Wheat, barley and finger millet as a major crop and lupine as a companion crop are food crops often traditionally grown in an intercropping in North Western Ethiopia. The experiment was conducted on intercropping of lupine (Lupinus albus L.) with wheat (Triticum aestivum), barely (Hordeum vulgar) and finger millet (Eleusine coracana) in 2009 at Adet Agricultural research station. The treatments were sole wheat at a seed rate of 175 kg/ ha, sole barley at a seed rate of 125 kg/ ha, sole finger millet at a seed rate of 30 kg/ ha, sole lupine at a seed rate of 90 kg/ h and 25, 50 and 75% of the sole lupine seed rate combined with each full cereal seed rate to determine the effect of lupine intercropping and seed proportion on the growth, yield and yield component; and lodging of wheat, barley and finger millet. The trial layout was a completely randomized block design with three replications. SAS software's were used to compute the analysis of variance. Increasing in lupine seed proportion in a mixture, delay in finger millet days to heading and maturity also significantly increased. The yield and yield component of most cereals were not significantly affected when they were intercropped with lupine in all seeding ratios except finger millet plant height, harvest index and wheat total biomass yield. Hence, growing cereals in association with lupine was not showed its yield reduction and the farmer's primary objective of maintaining a 'full' cereal yield was attained. Intercropping lupine with cereals gave physical support for cereals particularly in high lupine seed proportion. The combined yield advantage was greater than one in the cases of lupine-wheat followed by lupine-finger millet mixtures at all seeding ratios. Hence, two of the best combinations which were gave higher land use efficiency are the lupine-wheat mixture at the 75:100 seeding ratio (49.4%) followed by the lupine-finger millet mixtures at the 75:100 seeding ratio (29.4%).

High molecular weight glutenins are often effective in identifying wheat (Triticum aestivum) genotypes with good baking quality. The high molecular weight glutenin subunit composition of Ethiopian cultivars and advanced lines was investigated to determine their influence on quality. Three alleles at Glu-A1, five at Glu-B1 and two at Glu-D1 and eleven different banding patterns were identified. Few cultivars had biotypes at Glu-A1 and Glu-D1 loci. There were highly significant differences between genotypes and banding patterns for the SDS-sedimentation test, mixograph development time, alveograph strength and loaf volume; but not for protein content. The frequency of subunits 5+10 among genotypes was 73%. The accumulation of high scoring alleles in our germplasm was without deliberate selection pressure towards high Glu-1 scoring alleles during breeding. Introductions from CIMMYT are widely used and such materials might have gone through selection and accumulation of such alleles at CIMMYT. Most of the studied materials had the required subunits of high quality scores and better values of the quality traits than originally thought. Therefore, the concern about poor baking quality is unlikely to be due to Glu-1 allelic variations alone.Key Words: Allelic variation, grain quality, HMW glutenins RÉSUMÉLe poids moléculaire élevé des glutanines est souvent un moyen efficace pour identifier les génotypes du blé (Triticum aestivum) doté de bonnes qualités patissières. Une investigation était faite sur le poids moléculaire élevé des glutanines des sous unités des cultivars éthiopiens ainsi que sur des lignées avancées pour déterminer leur influence sur la qualité. Trois allèles à Glu-A1, cinq à Glu-B1 et deux à Glu-D1 ainsi que onze différents modes de bandage étaient identifiés. Peu de cultivars avaient des biotypes à Glu-A1 et Glu-D1 loci. Une différence hautement significative était observée entre génotypes et modes de bandage pour le test de sédimentation SDS, le temps de développement de mixographe, la force de l'alvéographe et le volume du pain mais non au contenu en protéines. La fréquence des sous unités 5+10 parmi les génotypes était 73%. L'accumulation des allèles à score plus élevé dans notre germoplasme avait eu lieu sans sélection délibérée de la pression des allèles à score plus élevé en Glu-1 pendant le breeding. Des introductions de CIMMYT sont largement utilisées et de tels matériels devraient passer par la sélection et l'accumulation de telles allèles au CIMMYT. La plupart des matériels étudiés possédaient de sous unités requises avec de scores de haute qualité et meilleures valeurs de traits de qualité qu'on ne le pensait originellement. Par conséquent, le problème concernant la pauvre qualité patissière n'était pas seulement dû aux variations alléliques Glu-1.

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In Ethiopia, durum wheat is largely used for production of local fermented and flat bread. Two diverse environments (Motta and Adet) were used to evaluate 15 durum wheat genotypes for grain yield and quality traits. The mean flour protein content of genotypes ranged from 10.1 % to 12.5 % and 6.7 % to 8.1 % at Motta and Adet respectively. The mean mixograph development time was 4 min at Motta and 2.8 min at Adet and SDS (Sodium dodecyl sulphate) sedimentation ranged between 10.7 and 32.3 ml across locations. Flour protein content was correlated negatively with mixograph development time and positively with vitreous kernels and single-kernel hardness at both environments. Mixograph development time was selected to predict the gluten strength. Flour protein content, SDS sedimentation and seed weight were included in a stepwise regression. A prediction model was compiled that explained 69 % of the variation for mixograph development time.