Estimation of Genetic Variance on Tea (Camellia sinensis (L.) O. Kuntze) Clones based on Morphological Markers in Southwestern Ethiopia Estimation of Genetic Variance on Tea (Camellia sinensis (L.) O. Kuntze) Clones based on Morphological Markers in Southwestern Ethiopia Mohammedsani Zakir 1 *, Melaku Addisu 2 and Kassaye Tolessa (PhD) 3 1,2 Ethiopian Institute of Agricultural Research, Jimma Agricultural Research Center, P.O. Box: 192; Jimma, Ethiopia 3 Ethiopian Institute of Agricultural Research Head Office, P.O. Box: 2003; Addis Abeba, Ethiopia Tea (Camellia sinensis (L.) O. Kuntze) Clones were characterized based on morphological traits to study genetic variation using randomized complete block design during 2017/18. The results showed highly significant (p<0.01) variance among genotypes of all traits. The phenotypic coefficient of variation (PCV) for all the characters was slightly higher than genotypic coefficient of variation (GCV), which signified the presence of environmental influence to some degree in the phenotypic expression of characters. Relatively wide ranges were recorded for number of shoot per tree (67.9-97.5 no./tree), hundred shoot weight (145.8-165.1 g) and leaf size (87.2-104.6 cm 2 ), number of days from medium pruning to first harvest varied (102.9-114.4 days). Accordingly, medium GCV and PCV were recorded for petiole length and number of shoots per tree. All traits considered in the study exhibited high heritability. Genetic gain (GAM) that expected from selecting the top 5% of the genotypes as percentage of the mean, varied from 3.84% for canopy diameter to 21.62% for petiole length. Accordingly, the high GAM recorded for petiole length (21.62%) and number of shoot per tree (20.62%). High phenotypic diversity on qualitative traits was recorded for leaf margin (0.93) and leaf shape (0.83). Therefore, this implies greater effectiveness of selection and improvement to be expected in future tea breeding program. Keywords: Clones, genetic advance, genotypic variation, heritability, location, tea INTRODUCTION Tea (Camellia sinensis (L.) O. Kuntze) is a standout amongst the most prominent and lowest cost type beverages in the world and consumed next to water by a wide range of age groups in all levels of society with more than three billion cups every day around the world (Phong et al., 2016). The tea plant belonging to family Theaceae is a small evergreen, perennial and develops normally as tall as 15 m. However, under cultivated conditions, a bush height of 60-100 cm kept for harvesting the tender leaves and the plant usually having an economic life span of 50- 60 years (Yemane et al., 2008). Nowadays commercial tea population includes three species, viz China type (Camellia sinensis (L.) O. Kuntze), Assam type (Camellia assamica (M.) Wight), Cambod type (Camellia ssp. Lasiocalyx planch. ex. Watt Weight) and their subordinates (Smith and Barua, 2011). World tea production (black, green, instant and other) come to 5,954,091 tons while top five producers were China (2,414,802 tons) 40.56%, India (1,252,174 tons) 21.03%, Kenya (473,000 tons) 7.94%, Sri Lanka (349,308 tons) 5.87% and Turkey (243,000 tons) 4.08%. Ethiopia existed at 21 th in the area of production of 9,727ha and 23 th in production from 47 tea delivering nations by producing (10,806 tons) 0.18% (FAOSTAT, 2016). Tea plant is cross-pollinated, that majority of species are diploid with chromosome number 2n=2x=30 (Kamunya et al., 2010). The out-breeding characters of tea species have led to a wide natural hybridization resulting in considerable heterogeneity in the existing populations; therefore, it is difficult to assign a definite varietal status to *Corresponding Author: Mohammedsani Zakir; Ethiopian Institute of Agricultural Research, Jimma Agricultural Research Center, P.O. Box: 192; Jimma, Ethiopia. Email: mohammedsani641@gmail.com Research Article Vol. 7(1), pp. 641-647, March, 2020. © www.premierpublishers.org, ISSN: 2167-0449 International Journal of Plant Breeding and Crop Science