Phenotypic Diversity in Arabica Coffee Genotypes from Eastern Ethiopia

Abstract

This study was conducted with objective to determine extent of phenotypic diversity in Arabica coffee accessions from Eastern Ethiopia. Treatments consisted of 49 coffee accessions. The accessions were field planted at Mechara Agricultural Research Center in July, 2005 using simple lattice design with two replications. Total of 15 quantitative characters were recorded using standard coffee descriptors. The collected data were subjected to SAS software for Analysis of variance. Cluster analysis was also done. Mean squares due to coffee accessions were highly significant (p<1%) for all quantitative characters studied except for number of internodes of main stem and average length of primary branch, indicating the presence of remarkable phenotypic variation among the coffee accessions studied. For stem characters, plant height varied from 94.00 to 165.40 cm; number of internodes of main stem ranged from 17.90 to 24.80 cm; internode length of main stem varied from 5.30 to 8.25 cm; diameter of main stem from 3.40 to 5.35 cm. For branch characters, number of primary branches ranged from 30.20 to 43.10; length of primary branch from 43.10 to 105.10 cm; numbers of internodes of primary branch 14 to 26.70; internode length of primary branch was from 3.20 to 5.73 cm; numbers of secondary branch varied from 41.10 to 133.20. For leaf characters, leaf length varied from 9.20 cm to 18.43 cm and with mean of 13.40 cm. Leaf width from 3.49 to 8.77 cm with mean vale of 6.24 cm. Average leaf area of all accessions was 57.96 with variation from 24.63 to 105.45 cm 2 . Weight of hundred beans ranged from 11 g for five accessions (H-25/04, H-40/04, H-41/04 and H-618/ 98) to 16.5 for H03/04 with mean value of 13.53 g. Cluster analysis grouped the coffee accessions into five groups of different sizes, ranging from one entry in cluster IV and V to 34 in cluster I. Inter-cluster distances were highly significant (p=0.01) except between cluster I and II, indicating presence of considerable phenotypic diversity in coffee accessions from eastern Ethiopia. It is advisable to maintain and evaluate the coffee genotypes for disease resistance, moisture stress tolerance, yield and cup quality in future studies.

Agro‐morphological characterization and diversity analysis of Coffea arabica germplasm collection from INIA, Peru

“…The variations found in the quantitative characters LFB, NNB, and LIN agree with what was reported by Adem et al. (2020), Berksisa et al. (2021), Atinafu and Mohammed (2017b), and Weldemichel et al.…”

“…Furthermore, Olika et al (2011) and Hedrick (2009) mention that the prevalence of such variability in an autogamous species such as C. arabica is very important and that can be attributed to evolutionary trends or natural mutations that occur within the population. In general, previous research has reported similar results to those observed in this work, determining high genetic diversity in coffee accessions through the study of quantitative and qualitative characters (Adem et al, 2020;Alemayehu, 2019;Atinafu & Mohammed, 2017b;Beksisa et al, 2021;Tounekti et al, 2017;Weldemichael et al, 2013Weldemichael et al, , 2017.…”

“…(2021) and Adem et al. (2020), classified 49 accessions into 3 and 5 groups, respectively. In Guatemala, Nakamura et al.…”

“…(2016). Dispersion graphs have been widely used to discriminate accessions in different crops (Aghaee et al., 2010), so that the study of their results together with the grouping analysis, are of great importance in breeding programs that they seek to adequately select the least related parents that come from distant groups and that contribute desirable alleles at different loci to the resulting progeny (Adem et al., 2020; da Fonseca et al., 2006).…”

“…Seven coffee accessions of the germplasm collection, due to adverse conditions, have less than 5 plants, for this reason they were not included in the present study. Nineteen quantitative characters and 1 qualitative character were evaluated, divided into 10 agronomic and 10 morphological descriptors, which are defined as follow: plant height (PH) measured from the ground level to the apical bud of the plant; trunk diameter (TD) measured at 5 cm from soil level; number of branches per plant (NBP); number of fruit‐bearing branches (NFB); length of fruit‐bearing branches (LFB) of the middle third of the plant; number of nodes per branch (NNB), measured from four fruit‐bearing branches; length of internodes (LIN) obtained from the LFB divided with the NNB; orthotropic internode length (OIL), obtained from the division of the PH and the number of orthotropic nodes; degree of plant inclination (DPI) according to an arbitrary scale where 1 = vertical trunk, 2 = trunk with slight inclination (<20°), 3 = moderately inclined trunk (20° to 45°), 4 = trunk very steep (>45°); leaf area (LA) from leaves of the fourth node of a branch located in the middle third of the plant, obtained by the product of the length (L) and width (W) of the leaf multiplied by the constant 0.68 (L × W × 0.68) (Adem, 2020); fruit geometric diameter (FGD) and seed geometric diameter (SGD), determined as the cube root of the average diameter of the length, width, and thickness of 10 fruits and grains per repetition of each accession; weight of a hundred fruits (WHF); fruit production per plant (FPP), corresponding to the cumulative harvest of the first five seasons (2017–2021); percentage of vain fruits (PVF), calculated by the number of floating fruits from a sample of 100 physiologically mature and apparently healthy fruits (Adem et al., 2020; Atinafu et al., 2017; Beksisa et al., 2017; International Plant Genetic Resources Institute, 1996; Ivoglo et al., 2008; Merga et al., 2019; Olika et al., 2011; Tounekti et al., 2017; Weldemichael et al., 2013). Likewise, the damage caused by the presence of the coffee berry borer ( Hypothenemus hampei ) was recorded, expressed as the percentage of infestation evaluated in 300 fruits per plant (PFB).…”