Deciphering Genetic Variability and Trait Associations in Coffea canephora : Insights From Half‐Sib Family Field Assessment

The use of better‐quality varieties is a critical necessity in any crop production system. The knowledge and usage of information regarding genetic parameter estimates would undeniably guarantee the success of any breeding program as regards variety development. The present study was therefore set up to gauge the level of genetic diversity among half‐sib robusta coffee families in yield and yield‐related traits, determine the relationship among key agronomic traits, and identify best‐performing robusta coffee genotypes. Twenty‐three half‐sib families and one standard variety were field‐planted in 2016 following a randomized complete block design with four replications and assessed for growth and yield traits over a 9‐year period. Significant ( p < 0.05) differences were found among the families for all traits except leaf chlorophyll fluorescence. With the exception of length of laterals and leaf chlorophyll fluorescence, moderate‐to‐high heritability estimates (0.42–0.75) were observed for all traits reflecting an encouraging outlook for selection to improve these traits in variety development. Our analysis also revealed that early year average yield may to some extent be a good proxy to select for yield in later years ( r = 0.92, p < 0.0001) or total yield ( r = 0.96, p < 0.0001). Exploiting these associations may likely facilitate the breeding process of the crop. Cluster analysis grouped the half‐sib families into two main groups that could guide parental selection and future hybridization efforts. Principal component (PC) analysis showed that stem diameter, plant height, span, number of laterals, cumulative yield, and first 3‐year average yield influenced the variation the most among the evaluated half‐sib families on the first PC axis. The top 26% of the half‐sib families based on cumulative yield (U17, U57, U41, U67, U62, U24) are recommended for further testing through ortet selection following cup quality determination, and disease and pest reaction assessment.