Plant Genetic Resources: Characterization and Utilization cambridge.org/pgr Research Article Cite this article: Alemayehu D, Garedew W, Tesfaye Abebe A (2022). Phenotypic characterization of Amaro coffee (Coffea arabica L.) local accessions using multi-variate techniques at Awada, Southern Ethiopia. Plant Genetic Resources: Characterization and Utilization 1–9. https://doi.org/10.1017/ S1479262122000119 Received: 19 June 2021 Revised: 12 April 2022 Accepted: 20 April 2022 Key words: Clustering; Coffee arabica; phenotypic characterization; principal component; Shannon–Weaver index Author for correspondence: Abush Tesfaye Abebe, E-mail: At.Abebe@cgiar. org © The Author(s), 2022. Published by Cambridge University Press on behalf of NIAB Phenotypic characterization of Amaro coffee (Coffea arabica L.) local accessions using multi-variate techniques at Awada, Southern Ethiopia Desalegn Alemayehu 1 , Weyessa Garedew 2 and Abush Tesfaye Abebe 3 1 Jimma Agricultural Research Center, Jimma, Ethiopia; 2 Jimma University, College of Agriculture and Veterinary Medicine, Jimma, Ethiopia and 3 International Institute of Tropical Agriculture, Ibadan, Nigeria Abstract As a country of origin of coffee, Ethiopia is endowed with an immense diversity of the crop in its diverse coffee-growing agro-ecologies. Amaro Kelo is one of the major coffee production agro-ecologies in Ethiopia, where the genetic diversity of its landrace coffee germplasm was not properly characterized previously. The study aimed to characterize 64 Amaro Kelo local coffee accessions to understand the potential of the accessions for utilization in future coffee genetic improvement efforts. The experiment was laid out in an 8 × 8 simple lattice design with two replications at Awada Agricultural Research Sub-Center. Datawere collected on 19 quantitative and 10 qualitative traits, and subjected to multivariate analyses, i.e. cluster and principal component analyses. The cluster analysis identified five clusters based on the quantitative characters, and the distances between most of the clusters were highly significant at P < 0.01. Principal component analysis revealed the first six principal components with Eigenvalues greater than one accounted for 77.7% of the total variation. The first two principal components with respective contributions of 23.32 and 18.85% cumulatively accounted for 42.2% of the total variation in the accessions. In addition, high values of Shannon-diversity index were found for the qualitative traits: branching habit, growth habit, fruit shape, overall appearance and stem habit. In general, the multivariate analyses confirmed the presence of high variation among the studied Amaro-Kelo coffee accessions that might serve as an important genetic resource for future coffee genetic improvement or conservation efforts. Introduction Arabica coffee (Coffea arabica L.) is predominantly grown in the tropical and subtropical regions of the world (Berthaud and Charrier, 1988; Davis et al., 2012). It is the only allotetra- ploid species of the genus (2n =4x = 44) (Lashermes et al., 1999; Benti et al., 2020). Coffee is one of the most important beverages globally (Labouisse et al., 2008), ranking second after oil in international trade (Geromel et al., 2006; Hameed et al., 2018). More than 2.5 billion cups of coffee are consumed daily across the globe (Coffee Industry Statistics, 2020), with 1.8–2.0% annual growth in consumption globally (Hameed et al., 2018; ICO, 2020), and 17% yearly growth of global green bean production and consumption in the past decade (Hameed et al., 2018). Ethiopia is one of Africa’s most important Arabica coffee-producing and exporting countries and the sixth most important coffee producer worldwide (ICO, 2018; USDA, 2018). The crop is mainly produced in the southern, southwestern and eastern parts of the country. The total area coverage of coffee in Ethiopia is estimated to be 758,523.29 ha, of which about 95% is produced by 4 million smallholder farmers (CSA, 2020). The estimated annual national production of coffee was 8.04 million of 60 kg bags, while the average national productivity was about 636 kg/ha (CSA, 2020). The plateaus of central Ethiopia are reported as the origin of Arabica coffee from a rela- tively recent hybridization between Robusta coffee (Coffea canephora Pierre ex A. Froehner) and C. eugenioides S. Moore or their ecotypes (Tesfaye et al., 2007; Lashermes et al., 2011). Arabica coffee has its primary centre of origin and diversity in the highlands of southwestern Ethiopia (Charrier and Berthaud, 1985; Wrigley, 1988; Belachew, 2000). It is the species nat- urally occurring in Ethiopia and South Sudan (Davis et al., 2012). As the centre of origin of Arabica coffee, Ethiopia is endowed with rich genetic resources of coffee in its diverse coffee- growing agro-ecologies (Hindorf and Omondi, 2011; Benti et al., 2020). Amaro Kelo, where the local coffee accessions used in this study were collected, is one of the major coffee produc- tion agro-ecologies with high diversity of the crop in the country. Agro-morphological traits, such as size and shape of leaf and plant form, colour of the shoot tip, characteristics of the fruit, angle of branching and length of internodes, are vital https://doi.org/10.1017/S1479262122000119 Published online by Cambridge University Press