Metaxenic effect of seven pollen sources on biometrics and ripening rate of three cultivars of date palm (Phoenix dactylifera L.) cultivated in the Ziban region (Algeria)

This study investigates the metaxenic influences of seven pollen sources on the biometric characteristics and maturity rates of three cultivars of Phoenix dactylifera L. (Deglet Nour, Ghers, and Mech Deglat) cultivated in the Ziban region of Algeria. Metaxenia, the effect of pollen on post-fertilization fruit growth, is essential for enhancing fruit quality and optimizing production timing. Pollen from seven genetically diverse sources (DN, GRS, MD, HMR, HLW, LTM, and BHS) was utilized to pollinate the cultivars, evaluating effects on fruit size, weight, ash content, and moisture levels. Notable discrepancies were noted among the attributes. MD pollen facilitated the most rapid ripening in Deglet Nour and Ghers, but LTM achieved optimal ripening in Mech Deglat at the Kimri stage. The ripening rates varied during the Tamer stage, with HMR recording the highest setting rates: 58.7% ± 2.8% for Deglet Nour, 36.9% ± 4.0% for Ghers, and 60.8% ± 3.6% for Mech Deglat. In contrast, GRS demonstrated the lowest ripening rates, varying from 13.1% to 29.8%. Concerning moisture content, MD pollen exhibited the highest levels in Deglet Nour (23.9%), BHS in Ghers (23.96%), and DN in Mech Deglat (21.81%). Biometrically, GRS on Deglet Nour and BHS on Ghers and Mech Deglat yielded larger, heavier fruits with superior flesh-to-seed ratios. These findings underscore the significance of choosing ideal pollen sources to enhance date palm fruit quality in arid locations, providing practical recommendations for agronomists and horticulturists. Additional research is advised to investigate the genetic mechanisms that govern these metaxenic effects.