Use of multivariate analysis to assess phenotypic diversity of date palm (Phoenix dactylifera L.) cultivars

Twenty one date palm (Phoenix dactylifera L.) accessions originated from different date palm groves were studied to assess the overall degree of polymorphism, detect similarities between genotypes and assess important agronomic traits. Thirty vegetative and reproductive variables were scored and subjected to multivariate analysis. Results showed a considerable phenotypic diversity among local date palm germplasm. Principal component analysis (PCA) revealed that characters related to leaflets length and spine, fruit and seed sizes accounted for a large proportion of the observed variability. Cluster analysis (CA) showed a typically continuous phenotypic diversity among date palm accessions and little associations between accessions from same geographic origin. Also, some heterogeneity within accessions that received the same denomination was evidenced.

Research highlights▶ Multivariate analysis is a powerful tool to explore phenotypic diversity of date palm cultivar. ▶ A considerable phenotypic (and presumably genetic) diversity exists among date palm accessions. ▶ Leaflets, fruit and spines traits greatly discriminate date palm cultivars. ▶ The denomination “Ahmar” is probably given to different date palm varieties.