Abstract

Like other fruit trees, pomegranate (Punica granatum L.) shows significant variations in pomological and chemical characteristics depending on harvest year and tree age. However, the combined effect of these factors on fruit quality remains little explored, particularly in the context of ex-situ collections over several years. Gaining a deeper understanding of these variations is essential for guiding breeding programs and optimizing fruit quality management.

Comme pour d’autres arbres fruitiers, les propriétés pomologiques et chimiques de la grenade, (Punica granatum L.) peuvent varier d’une année à l’autre et en fonction de l’âge de l’arbre.

pomologiques et chimiques peuvent varier d’une année à l’autre et en fonction de l’âge des arbres. Like other fruit trees, for the pomegranate (Punica granatum L.), the pomological and chemical properties can vary between years and depending on the age of the trees. Physicochemical screening of 19 pomegranate cultivars belonging to an ex-situ Moroccan collection, for fruits harvested from three different years, showed highly or very highly significant variations for most traits. Indeed, fruit weight, diameter and height were relatively higher in 2017, exceeding the values recorded in 2018 by 22.8%, 13.5% and 4%, respectively. In addition, the weight and length of the aril and some chemical properties, pH, total soluble solids brix degrees and maturity index, presented higher values in 2017, exceeding those recorded in 2018 by 3%, 7% and 3%, 14% and 80%, respectively. For the average of the three harvest years, the Chelfi; cultivar has the lowest weight, while the khikhou has the highest value. The weight and yield of the arils vary respectively between 266 mg (OunH) and 670 mg (Khik); and 50.65 (Khik) and 73.34 (Gord). For chemical parameters, total soluble solids ranged from 14.52 (Grenade_Jaune) to 17.81 (Sefri 2) °Brix. The maximum value of titratable acidity has been found for ‘Negro_Monsteriosa’ (2.87%) and the minimum for ‘Grenade_Rouge’ (0.37%). The PCA analysis shows the distribution in groups according to the year of harvest which shows the annual variance of the traits. The hierarchical analysis shows the presence of gene pools without an obvious geographical structure. Thus, the results obtained constitute a basis for the breeding programs of the species.

Key words: Pomegranate; physicochemical parameters; harvest age effect; diversity; ex-situ collection