Assessment of phenotypic diversity of some date palm male genotypes growing under Egyptian conditions

Avaliação da diversidade fenotípica de alguns genótipos masculinos de tamareiras cultivadas sob condições egípcias

Abstract

Artificial pollination is a prerequisite to achieve a sufficient yield of palm trees; hence the identification of superior male palm trees as a standard pollen source for date palm growers has a high priority. The current study was carried out to assess phenotypic diversity among four date palm males namely Hayani, Meghal, Fardh, and Ghannami Ahmer. The genetic diversity and phylogenetic relationships between palm genotypes were performed using eighteen quantitative morphological parameters of both vegetative and reproductive parts (leaf, leaflets, spines, and spathe). Principal components analysis and hierarchical clustering was performed to identify the differences and similarities between the studied genotypes. Results showed significant differences in morphological parameters between the four male palm trees. Most of the selected morphological parameters could be used as quantitative markers for the identification of date palm male genotypes. Principal component analysis showed that, the studied parameters formed two major homogeneous groups of variables, which possessed a high proportion of the observed phenotypic diversity among the studied date palm males. Cluster analysis showed that Fardh, Ghannami Ahmer, and Meghal, are closer related than Hayani; Ghannami and Fardh males showed the highest genetic similarity while the lowest similarity index was detected between Hayani and Ghannami Ahmer males.

Index terms
Phoenix dactylifera; pollinizers; phenotypic diversity; morphological identification