Agro-Physiological and Pomological Characterization of Plum Trees in Ex-Situ Collections: Evaluation of Their Genetic Potential in the Saïss Plain

The aim of this research is to assess the genetic potential of plum cultivars in an ex situ collection at the National Institute for Agronomic Research in Meknes, Morocco, under the conditions of the Saïss plain. This is an essential preliminary stage in the study of varietal adaptation to climate change. Twenty-eight cultivars will be analyzed, using agro-morphological, physiological, and pomological descriptors. This characterization was based on measuring the genetic diversity of all the cultivars, production traits (yield, average weight, and fruit size), vegetative traits (leaf area, number of leaves per fruit, and shoot leaf load), physiological traits (stomatal traits, leaf proline content, cuticular wax, chlorophyll a and b) and the measurement of certain chemical and biochemical quality components of the fruit. The study of plum cultivars revealed significant variability in agronomic, vegetative, physiological, and pomological traits. Analysis using the Unweighted Pair Group Method enabled us to classify them into two main groups for all the characteristics assessed. This study will identify the cultivars best adapted to Moroccan conditions, thus meeting scientific, agronomic, and environmental objectives. Furthermore, the results of this research will have a significant impact on the management of the plum collection, ensuring not only the preservation of genetic diversity and the sustainability of the species, but also contributing to the promotion of sustainable agricultural practices. This will help optimize resource use, reduce environmental impact, and enhance crop resilience to climate change while supporting breeding programs.