Assessment of Genetic Diversity in Robusta Coffee Using Morphological Characters

Abstract

Assessing the level of genetic variation that exist in any breeding population is important as this has significant implications for selection and variety development. The objectives of the present study were to determine the variation among 71 Robusta coffee genotypes based on 21 traits and to determine the genetic relationships between the genotypes. The 71 genotypes were established in 2013 as clones raised from single node cuttings and planted in a randomized complete block design with four blocks, with five plants per genotype per block. There was variation in all the traits assessed for the different Robusta coffee genotypes as evidenced by the coefficient of variation and frequencies of the quantitative and qualitative traits, respectively. Principal Component Analysis (PCA) was performed to obtain information on the relative importance of the morphological characters assessed, and cluster analysis was used to determine relationships among the genotypes evaluated. The first and second principal components accounted for 39.2% and 18.9% of the total variability, respectively. PCA revealed that height, stem diameter, span, number of laterals per tree, diameter of laterals, and number of nodes per lateral were the principal characters to discriminate the Robusta coffee genotypes examined. Cluster analysis grouped the Robusta coffee genotypes into five clusters as revealed by the dendrogram. The diversity among the Robusta coffee genotypes in both quantitative and qualitative traits revealed by this study can be used for trait improvement through selection and hybridization.

Genetic variation among biparental Robusta coffee families and implications for variety development

“…Genetic variability and estimation of genetic parameters of key productivity traits are of significant importance to guide selection in a hybrid breeding programme. Though the gene pool of Robusta coffee in Ghana based on morphological characters has been determined to be narrow (Akpertey et al, 2018b), the results from the present study indicated the presence of variation among the families for most vegetative growth traits and all yield traits, based on which significant improvement could be made in the breeding of the crop in the country. The presence of the significant variation may be attributed to the larger number of families included in the study.…”

Frequency distribution and potence ratio of agronomic traits in F1 generation of intraspecific crosses of Robusta coffee.

“…We need to select the varied progenies of crosses for superior planting materials. Observing the agronomic character is crucial in supporting the success of a plant breeding program (Akpertey et al, 2019). For example, leaf size is related to plant adaptability and photosynthetic efficiency, while internode length can be used to estimate coffee productivity.…”

Effectiveness of Single Nucleotide Polymorphism Markers in Genotyping Germplasm Collections of Coffea canephora Using KASP Assay

“…Gene bank activities may be affected by improper identification, redundancy, and other errors because the trees in the germplasm plots were collected, exchanged, or otherwise obtained at different times with limited passport data on their correct identity. Moreover, limited knowledge on the level of genetic diversity of the C. canephora germplasm hinders their effective utilization in a breeding program ( Akpertey et al, 2019 ). Previous efforts on genotype identification and diversity assessment in the coffee germplasm collections in Ghana have relied largely on morphological characters ( Anim-Kwapong et al, 2010 ; Akpertey et al, 2019 ), which is limited because the environment tends to have a significant effect on phenotypic expression ( Souza et al, 2013 ).…”

“…Moreover, limited knowledge on the level of genetic diversity of the C. canephora germplasm hinders their effective utilization in a breeding program ( Akpertey et al, 2019 ). Previous efforts on genotype identification and diversity assessment in the coffee germplasm collections in Ghana have relied largely on morphological characters ( Anim-Kwapong et al, 2010 ; Akpertey et al, 2019 ), which is limited because the environment tends to have a significant effect on phenotypic expression ( Souza et al, 2013 ). Precise identification of plants in any germplasm collection is important to facilitate its management and utilization.…”