Agro-morphological traits assessment of Tunisian male date palms (Phœnix dactylifera L.) for preservation and sustainable utilization of local germplasm

Date palm (Ph oe nix dactylifera L.) like other crop species in the arid Mediterranean region is being threat-ened by genetic erosion and climate change. Therefore, the understanding and assessment of the diver-sity extent of this species is a primary requisite for preserving these crop resources. This study was designed to quantify the potential of Tunisian male date palms using a set of agro-morphological char-acteristics i.e. flowering traits, inflorescence morphology and pollen quality. The flowering time traits exhibited a trend of precocious phenotype at emergence spathe trait and the dominance of the full -season phenotype at the opening date. At inflorescence morphology, all observed traits expressed wide ranges which reflected the broad variability of the evaluated male genotypes. Significant difference was recorded for the majority of the examined traits with a high significant variation in the tree quanti-tative traits: Spathe Total Length, Spathe Maximum Width and Length to the brunched part. Pollen via-bility ranged from 51.10% to 98.75% while the germination rate was between 0.90% and 70.50%. Our phenotypic investigation has allowed the identification of males with desirable agronomic traits which have been genotyped using 18 nuclear SSR markers and a chloroplast minisatellite for preservation and effective utilization purposes.(c) 2023 The Authors. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Investigated the agronomic characteristics of Tunisian male date palms, identified males with desirable traits, and genotyped and preserved them for effective utilization.