Morphological Characterization and Diversity Analysis of Coffea Arabica Germplasm from Yirgacheffe, Ethiopia

This study aimed to assess the genetic diversity of twenty-six Coffea Arabica landrace germplasms collected from the Yirgacheffe district of the Gedeo zone depending on morphological characteristics at the seedling stage. Collected Coffea Arabica landrace germplasms seeds and 2 standard checks were planted and raised at Wanago Tumata Chiracha nursery site in plastic bags arranged with randomized complete design in the years 2022 to 2023. Seedling characteristics variables such as seedling height, number of paired leaves, leaf length, leaf width, leaf area, petiole length, node number, inter-node length, and stem diameter were collected from one year-old randomly selected three seedlings from each accession and each plot. The results revealed that there were significant variations (p<0.05) between and within collected Coffea Arabica landrace germplasms and standard checks for the above quantitative parameters. Data of five qualitative traits (young leaf color, leaf shape, leaf apex shape, leaf petiole color, and young shoot color) were recorded from three representative seedlings for each Coffea Arabica landrace germplasm accession. Frequency distribution estimation using Shannon and Weaver's diversity index results for qualitative parameters revealed the presence of genetic variability between the collected coffee germplasm accessions and standard checks. Accordingly, the highest diversity index (H) was recorded for young leaf color (1.414), followed by leaf shape (1.067) and leaf apex shape (0.908). This might be due to the oligogenic nature of gene action and slight environmental interaction. Relatively low diversity was observed in young shoot color (0.582) and leaf petiole color (0.429). Additionally, cluster analysis of qualitative parameters grouped 26 coffee landrace germplasm accessions and 2 standard checks into three clusters. Maximum numbers of coffee germplasm accessions were grouped in cluster-II (15) followed by cluster-I (9) and cluster-III (4). Consequently, Coffea Arabica landraces germplasm having high seedling height, leaf length, number of paired leaves and leaf area should get emphasis during selection for plantation. Moreover, every concerned body, such as breeders, farmers, and genetic conservationists should take action to conserve and keep the gene pool of these coffees since it paved the way for biotechnologists to characterize coffee at the molecular level and breeders consider it to release superior new coffee varieties.