Arabica coffee is a perennial cash crop and highly affected by biennial bearing which disturbs farmers’ annual income and world’s coffee industries. Developing nonbiennial bearing variety is prominent in addition to applying field management practices. This study was conducted from 2012 to 2020 in southwestern Ethiopia at Tepi and Gera to test the extent of genetic variability among Arabic coffee germplasm in biennial bearing and understand the influences of bienniality on advanced selection. The pooled analysis of variance revealed handiness of genetic variability in yield and biennial bearing. The moderate genotypic coefficient of variation (10–20%), heritability (30–50%), and high genetic advance as percentage of the mean (>20%) were manifested in yield and biennial bearing. Response to selection and selection efficiency were negatively affected by biennial bearing. Early selection excluded 30–40% of the top high yielders from advanced selection. Selection at four harvesting seasons revealed 90% and more selection efficiency. Thus, one has to be conscious of the alternate bearing nature of lines during advanced selection. Both T43/11 and T51/11 were among the top high yielders and showed low biennial bearing at Gera and Tepi. T33/11, T49/11, T55/11, and T61/11 showed very low biennial bearing at both locations. These are promising lines and could be recommended for further biennial bearing improvement breeding programs.

Coffea arabica L., the dominant cash crop in the world market, is native to rain forest of Ethiopia where it is believed to exist with high genetic diversity. Estimating genetic parameters are momentous in deciding breeding method to be followed for crop genetic improvement including Arabica coffee. The study was conducted with the intention to gauge genetic gain trend in coffee yield and to select advanced promising lines of Yayo coffee landrace for the next breeding step. The study was laid down at Metu research subcenter in 2013, using 124 coffee accessions that were established in simple lattice design under two sets each comprising 62 accessions including two checks. The over six years pooled analysis of variance indicated the handiness variability in yield performance among accessions. Moderate genotypic variance (15.46 to13.56), heritability (56.1681), and expected genetic gain (15.5220.8) were observed. The genetic parameters and the superiority of check in yield over accessions elucidated that high yielder variety development by selection is difficult unless heterosis attaining breeding method followed, particularly for these Yayo coffee landrace origin. Common high genetic gain trend (49.19 and 100kgha⁻¹) and response to selection (196.76 and 400kgha⁻¹), selection differential 471.9 and 739.23kgha⁻¹ were revealed in over four harvesting seasons mean value for both sets. Thus, selection is more effective in earlier season than late. High yielding accessions, Y27 and Y93, gave 3013.1 and 125.8kgha⁻¹ yield gain over the high yielder check correspondingly. Despite the top 15 and 10 high yielders were selected from set-I and set-II, respectively, a total of 20 accessions with contrasting desirable traits were selected and established in crossing block for genetic improvement purposes via heterotic hybrid variety development program. These accessions were tolerant to major coffee disease and have desirable agronomic traits.

Coffee quality is a complex trait influenced by both genetic compositions and environmental factors. In Ethiopia’s Limmu coffee‐growing area, the joint effect of genotype and environment on raw and cup quality attributes is still not well understood, restricting the choice of top hybrids for premium coffee production. This study examined the interactive effects of genetic and environmental factors on the raw and cup quality of Limmu coffee hybrids, emphasizing professional cupping evaluation. Seventeen coffee entities (10 crosses, 5 parental lines, and 2 standard checks) were cultivated across Jimma, Agaro, and Gera Agricultural Research Subcenters between 2019 and 2022 using a randomized complete block design (RCBD) with three replications. The washed processed beans were evaluated employing a completely randomized design (CRD) for raw and cup attributes by five certified Q‐grade cuppers following the Ethiopian Institute of Agricultural Research (EIAR) protocols. Physical quality comprised screen size (15%) and raw quality (40%), which included bean shape and make (15%), color (15%), and odor (10%). Cup quality (60%) included aromatic quality (5%), aromatic intensity (5%), acidity (10%), astringency (5%), bitterness (5%), body (10%), flavor (10%), and overall quality (10%). The results showed significant genotype‐by‐environment ( G × E ) interactions influencing both raw and cup quality. Hybrids L03/01 × L45/01 and L03/01 × L55/01 attained superior raw (36.11%–37.56%) and cup quality (42.61%–47.33%) scores, leading to high total quality (78.67%–84.39%). Pearson correlation analysis demonstrated strong positive relationships ( r = 0.82–0.91, p < 0.05) between total quality and key cup attributes, including acidity, body, flavor, bitterness, and overall quality. Highland sites, such as Gera, consistently raised sensory scores, underscoring the impact of altitude and temperature on coffee quality. Three hybrids, L67/01 × L45/01, L03/01 × L55/01, and L20/03 × L55/01, showed outstanding sensory performance confirmed by professional cuppers, providing promising opportunities for premium‐grade coffee and sustainable varietal improvement in Ethiopia.

Coffee (Coffea arabica L.) is the major cash crop of Ethiopia. The country is ecologically very diverse which allows the coffee plant to grow under wide range of environments between altitudes of 550 to 2600 m. a.s.l. Ethiopia, being the place of origin for Arabica coffee, is endowed with genetic pool wealth of the crop and with enabling environmental conditions to sustainably produce and supply fine specialty coffee that can address emerging international market demand. The prevailing wide range of ecological condition in the country has have allowed the production of coffees of different types that are with uniquely distinctive quality profile, resistance to major diseases, plant growth and yield potential among many other desirable traits. Of the coffees produced in Ethiopia, the most popular internationally branded types (named depending on area of production) are; Sidama, Yirga-cheffe, Limmu, Gimbi and Harerghe coffees. These specific coffee localities, despite their valuable potential and the recognition they deserved on the world market, were lacking their own improved local varieties where they had been using coffee varieties released for other areas (south-western region) until the 2010. However, most of southwest varieties showed multitude of constraints such as poor adaptation and inherent quality adulteration under the locations. Cognizant of this problem, local land race variety development program was designed and implemented to promote sustainable production of the distinct coffee types by origin maintaining inherent qualities of the specific localities for enhanced export market expansion. Through this breeding approach so far, outstanding achievements were recorded in germplasm collection, evaluation for desirable agronomical traits, and generation of basic information on the genetics aspects, and development and release of 12 speciality varieties suiting for the specific coffee landraces in Ethiopia, i.e., 4 Harerghe, 4 Wollega/Gimbi, 3 Sidama/Yirgachefe and 1 Limu coffees. As the main focus areas of future Arabica coffee landrace improvement program, it would be vital to give due attention to further identification of new and distinctive landraces, extensive collection of coffee genetic resource from unaddressed localities, application of molecular breeding techniques such as marker assisted selection and breeding for major /emerging/ diseases and stress tolerance, among others.

Ethiopia is the center of origin for Arabica coffee and has been dramatically working on improving coffee production technologies for the last 56 years. Coffee seedlings take a long time, and their qualities pose challenges in coffee production. To improve these, several studies implemented germination influences, factors, and storage periods. However, studies on varietal differences are limited, particularly those that simultaneously compare variations among varieties, which could serve as a basis for future breeding and improvement programs. Therefore, this study focused on comparison of differences in germination among 14 coffee varieties using a randomized complete block design with three replications at Jimma Agricultural Research Center. Analysis of variance (ANOVA) and mean comparison of significantly different traits were analyzed using R software of agricolae package. The germination, vigor, uniformity, and growth traits were analyzed. The results revealed immense variations in germination potential, vigor, and uniformity. The Haru‐1 variety exhibited superior growth parameters, including a mean node number of 1.44, internode length of 2.74 cm, and plant height of 9.11 cm. Among the studied varieties, Menesibu stood out in root fresh weight (0.43 g), Mocha in shoot fresh weight (2.67 g), and Qoti in shoot‐to‐root ratio (9.56), respectively. In contrast, Fayate showed the poorest performance across most growth parameters, except for plant height, in which Geisha recorded the lowest value. Environmental factors means apply managements at seedling stage. Thus, Arabica coffee varietal differences during early germination and growth stages arise from genetic diversity, seed structure, hormonal balance, and environmental adaptation. Understanding these factors helps optimize germination protocols and seedling management for better crop performance. Based on this study’s findings, Fayate variety showed highest performance as compared to the others under controlled nursery condition and the same management. This superior performance indicates that it may possess genetic, nongenetic, or a combination of factors that differ from the studied varieties. Therefore, the repeatability and factors behind the differences need further study to get viable seed and uniform coffee seedlings.