The seeds used originated from two distinct sites: Aoulouz, located to the west at the bottom of the Souss plain at the foothills of the High Atlas Mountains (altitude: 700–850 m; average annual rainfall of approximately 232 mm; mean minimum and maximum temperatures of 5.6 °C and 35.7 °C, respectively), and Lakhssas, situated to the south in the Guelmim region (altitude: 916–988 m; annual rainfall of approximately 189 mm; mean minimum and maximum temperatures of 7.3 °C and 31.2 °C, respectively).

The experiment involved twelve one-year-old plants grown in 15 × 15 cm pots containing a substrate composed of a 4:1 mixture of forest soil and peat, and evenly distributed between the two ecotypes and the two experimental conditions (water stress and control). Metabolite identification was carried out using an analytical technique combining gas chromatography and mass spectrometry (GC–MS).

Under water stress conditions, statistical analysis (t-test, p < 0.05) identified 44 metabolites significantly affected in the Lakhssas ecotype and 56 in the Aoulouz ecotype.

A volcano plot was then used to distinguish overexpressed and underexpressed metabolites under water stress. In this graph, the log₂ fold change (log₂FC), representing the relative variation in metabolite abundance between water-stressed and control conditions, is plotted on the x-axis, while the y-axis (−log₁₀(p)) indicates statistical significance. Metabolites located on the right side of the graph (positive log₂FC) correspond to overexpressed metabolites (significantly higher concentration under water stress compared to the control), whereas those on the left (negative log₂FC) are underexpressed (significantly decreased concentration under water stress compared to the control). Accordingly, 34 metabolites were overexpressed and 10 underexpressed in Lakhssas, while in Aoulouz, 25 metabolites were overexpressed and 31 were underexpressed.

The relative importance of each metabolite was assessed using Variable Importance in Projection (VIP) analysis, which allows identification, within a multivariate model, of compounds contributing most to the discrimination between the two ecotypes. Based on this analysis, twenty metabolites with a VIP score ≥ 1, indicating a significant contribution, were selected.

Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) revealed a clear separation between control samples and those subjected to water stress. Based on the importance of variables in projection scores as well as receiver operating characteristic (ROC) curve analyses, ten potential biomarkers of drought tolerance were identified.

In the Aoulouz ecotype, two overexpressed metabolites, M65 (lupeol) and M102 (octadecane), as well as three underexpressed metabolites, M108 (octacosane), M123 (5-octadecene, E), and M200 (diethyl ester of 4-nitrobenzylidenemalonic acid), were found to be determinant. In contrast, the Lakhssas ecotype exhibited five overexpressed biomarkers: M6 (methyl hexadecanoate), M54 (1,3,6,10-cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)), M88, M91, and M142.

Metabolites M65 and M102 in Aoulouz likely contribute to strengthening cuticular integrity and mitigating oxidative stress responses. Conversely, the overexpression of M6 and M54 in Lakhssas suggests an adaptation strategy relying more heavily on lipid signaling and energy metabolism. However, this ecotype may prove less resilient to prolonged drought due to a greater capacity for metabolic reallocation.

In conclusion, the study demonstrates that the two ecotypes adopt distinct strategies: the Aoulouz ecotype develops durable tolerance through reinforcement of the cuticle and improved management of oxidative stress, while the Lakhssas ecotype relies on transient metabolic adjustments. These findings are valuable as they link measurable metabolic signatures to effective physiological strategies, paving the way for practical applications in plant breeding and sustainable agriculture under water stress conditions.

Réf. Rabeh K., Farid Rachidi F., Sbabou L. et al.,2025 - Potential metabolite biomarkers of drought tolerance in contrasting Sideroxylon spinosum L. ecotypes using a metabolomic approach. J. Sci. Food Agric. (wileyonlinelibrary.com) DOI 10.1002/jsfa.70365

More specifically, the analysis focuses on the entire body of scientific literature related to argan oil—whether its nutritional, cosmetic, or medicinal uses—as well as on the biology, ecology, and conservation issues surrounding the argan tree. It also covers the applications of remote sensing for mapping and monitoring the spatio-temporal dynamics of argan woodlands. The ultimate goal is to highlight existing sustainable management practices and identify the main challenges ahead.

The quantitative analysis of scientific output was carried out using the Bibliometrix software package and its Biblioshiny interface, powerful tools based on the R language that enable the examination of a research field’s structure, evolution, and dynamics through advanced network analysis and visualization methods. The construction and representation of networks (keyword co-occurrence, author collaboration, co-citations, citations) were performed with the VOSviewer software.

The first stage of the analysis focused on the scientific literature devoted to argan oil. Between 1992 and May 2024, six hundred contributions were recorded. Examination of the co-occurrence of the 2,678 keywords from this corpus reveals three thematic clusters that are strongly interconnected.

The first group (16 items) concerns the effects of argan oil on health and includes notions such as “phenolic compounds” and “oxidative stress.” The second group (also 16 items) relates to the assessment of oil quality and its health implications, featuring keywords such as “adulteration” and “tocopherol.” The third group (11 items) refers to the botanical characteristics of the argan tree and its ecological role in Morocco.

The analysis of six hundred publications highlights a marked increase in scientific output starting in 2009, as well as the diversity of contributors, research hubs, and collaboration networks. Unsurprisingly, Morocco—where the argan tree is an endemic species—holds the leading position in this field. Moroccan institutions also maintain numerous partnerships with French and German establishments.

The second phase of the analysis focuses on studies dedicated to the ecology and physiology of the argan tree. Between 1992 and 2024, three hundred and ninety contributions were recorded. Examination of the co-occurrence network of the 134 most frequently used keywords in this literature reveals seven major research themes: the biochemical, molecular, and biological properties of argan compounds; ecological, physiological, and conservation-related dimensions; ecology, management, and uses; physiological responses to abiotic stress; growth and development; genetics, ecology, and evolutionary biology; as well as environmental processes and management strategies.

In recent years, the integration of advanced remote-sensing and machine-learning techniques, relying on multi-source satellite imagery, has significantly improved the mapping and monitoring of argan woodlands, thereby contributing to the conservation and sustainable management of this forest ecosystem.

Réf. El Moussaoui EH., Moumni A., Khabba S. et al., 2025 Bibliometric and review analysis of argan trees studies: global research trends and challenges. Agroforest Syst, 99:132 https://doi.org/10.1007/s10457-025-01228-2

Réf. Homrani Bakali A. & Khamar H., 2025 New records and floristic notes on the genus Oenothera (Onagraceae) in Morocco. – Botanica, 31(4): 142–154. https://doi.org/10.35513/Botlit.2025.4.1

The results derived from the three datasets are fully congruent: the four analyzed populations of Nepeta nepetoides form a well-supported, distinct clade that is sister to other members of the subtribe Menthinae, rather than to those of the Nepetinae. Consequently, this species should no longer be retained within the genus Nepeta but must be transferred to the genus Pitardia.

Pitardia can be distinguished from Nepeta by several diagnostic morphological traits: the presence of two stamens and the absence of staminodes (four stamens in Nepeta), a calyx tube with 10 veins (typically 15 [13–17] in Nepeta), and a convex, entire median lobe of the lower corolla lip (usually crenate in Nepeta).

Ref. Homrani Bakali A., Dirmenci T., Celep F. & Drew B.T., 2025 - Pitardia resurrected: A new member of subtribe Menthinae (Lamiaceae). Taxon, https://doi.org/10.1002/tax.70053

Molecular data suggest that the divergence between E. balsamifera and E. adenensis occurred during the Pliocene, a period spanning approximately 5.3 to 2.6 million years ago. This era coincides with a major episode of climate aridification in the subtropical regions of the Old World, leading to the fragmentation of forest habitats in favor of more open and arid landscapes. These new environmental conditions likely facilitated a rapid adaptive radiation of the ancestral group, meaning the emergence of several lineages specialized for arid habitats.

In this context, E. balsamifera is thought to have colonized the Canary Islands from northwestern Africa. This colonization may be explained by the "surfing syngameon" mechanism—an evolutionary hypothesis in which a flexible gene pool (or syngameon) "surfs" waves of dispersal into new territories while maintaining sufficient genetic diversity to allow rapid adaptation to novel environments.

Computer models using convolutional neural networks (a form of artificial intelligence) suggest that E. balsamifera first settled on the eastern islands (Lanzarote, Fuerteventura), before migrating westward (Tenerife, Gran Canaria).

Contrary to what one might assume, the populations in North Africa are not remnants of an ancestral continental population. Instead, they result from migratory events originating from the islands of Lanzarote and Fuerteventura. These back-colonization events likely occurred during the Middle Pleistocene, although this still requires confirmation.

This finding challenges the notion that islands merely "receive" genetic diversity from the continent. In this case, the Canary Islands actually generated new genetic diversity that subsequently spread back to the African mainland.

Ref. : Rincón-Barrado M., Villaverde T., Perez M.F., Sanmartín I. & Riina R., 2024 - The sweet tabaiba or there and back again: phylogeographical history of the Macaronesian Euphorbia balsamifera. Annals of Botany 133 : 883–903. https://doi.org/10.1093/aob/mcae001, available online at www.academic.oup.com/aob

The literature search was conducted using the same keywords in the Scopus and Web of Science databases, selecting publications in English and French published between 2000 and 2024. Using the PRISMA method, 55 articles were selected, the majority of which (36) originate from Morocco, the native country of the argan tree.

The bibliometric analysis, performed using the VOSviewer software, enabled the visualization of links between the main keywords related to argan tree research. This map highlights the central position of germination, around which micropropagation, seed sowing, in vitro culture, and vegetative propagation are organized.

The discussion compares the different techniques: seed germination, which has a low success rate, is contrasted with the advantages of cutting and grafting, which allow for rapid rooting and greater genetic stability. In vitro micropropagation also appears to be a promising method, although it requires strict acclimatization conditions.

In conclusion, the study emphasizes the importance of combining traditional methods with modern biotechnological approaches to ensure the reproduction and sustainable conservation of this emblematic species.

Ref. : Tesse R., Boutaleb F., Bahlaouan B., Brett-Crowther M., El Antri S., & Boutaleb N., 2025 - Micrografting and Other Regeneration Techniques for the Argan Tree (Argania spinosa): A PRISMA-Based Systematic Review and Meta-Analysis. Natural Built Social Environment Health 1(3). DOI :10.63095/NBSEH.25.180342

Ref. : Homrani Bakali H., Chatelain C. & Khamar H., 2025 - New non-native species recorded in cumin crop in southeastern region of Morocco. Botany Letters, DOI : 10.1080/23818107.2025.2506559 (18 Jun).

Réf. : Homrani Bakali H., Chambouleyron M. & Leger J.-F., 2025 - Santolina razaneae (Asteraceae), a new steppic species from Morocco. Phytotaxa 693 (3) : 235–244. https://doi.org/10.11646/phytotaxa.693.3.4.

Les résultats montrent que la croissance des plants d’arganier est maximale dans les conteneurs de plus grand volume (500 cm³), avec un substrat de culture spécifique composé d’un compost d’acacia (Acacia cyanophylla) à 100 % et un mélange à parts égales de terreau et de compost d’Acacia.

Cependant, comme souvent observé avec les plants élevés en conteneurs, ces derniers présentent des déformations de la racine pivotante, ce qui affecte la qualité globale des plants. Il convient de noter que le suivi des performances des plants après transplantation sur le terrain n’a pas été réalisé dans le cadre de cette étude.

Ainsi, le protocole optimal pour assurer une régénération efficace des arganiers reste à définir.

Réf. : Dallahi Y., Boujraf A., Smouni A. et al., Effects of container size and growing media on growth of argan (Argania spinosa) seedlings in Morocco. New Zealand Journal of Forestry Science (2024) 54:16 https://doi.org/10.33494/nzjfs542024x285x.

Pour ce faire, elle s’appuie sur huit modèles de circulation générale (GCM) intégrant deux scénarios d’émissions RCP (pour Representative Concentration Pathways ou profils représentatifs d’évolution de concentration). Les scénarios, établis en 2014 par le Groupe d’experts intergouvernemental sur l’évolution du climat (GIEC), traduisent différentes trajectoires possibles de la concentration en gaz à effet de serre (GES) et leurs conséquences climatiques pour le XXIe siècle et au-delà. L’étude compare le scénario RCP4.5 (scénario modéré prévoyant une stabilisation des émissions avant la fi¬n du XXIe siècle à un niveau faible) et le scénario RCP8.5 (scénario pessimiste où les GES continuent d’augmenter au rythme actuel) et porte sur deux horizons temporels : 2050 et 2070. La modélisation des déplacements des zones bioclimatiques repose sur la méthode Random Forest (RF), approche puissante qui utilise un ensemble d’arbres de décision pour générer des prévisions à la fois robustes et précises.

Les résultats indiquent logiquement que les changements les plus importants se manifestent dans les zones bioclimatiques associées au scénario RCP8.5 (scénario pessimiste), et ce, pour les deux horizons temporels étudiés : 2050 et 2070.

Les zones bioclimatiques subhumides et humides devraient subir des transformations significatives, évoluant progressivement vers des conditions semi-arides. Les transitions du subhumide au semi-aride sont estimées entre 17,91 % (scénario RCP8.5 en 2070) et 25,68 % (scénario RCP8.5 en 2050), des taux nettement supérieurs à ceux observés pour les changements de l'humide au semi-aride, qui oscillent entre 10,16 % (scénario RCP4.5 en 2050) et 22,27 % (scénario RCP8.5 en 2070).

La zone semi-aride devrait également connaître des modifications notables, avec une extension vers la zone bioclimatique aride variant entre 2,27 % (scénario RCP4.5 en 2050) et 34,30 % (scénario RCP8.5 en 2070). Par ailleurs, environ 10 % de la zone aride est prévue pour migrer vers le bioclimat saharien, tandis que la zone saharienne devrait demeurer relativement stable.

La discussion met en lumière les conséquences majeures de l’accélération du changement climatique sur les principales espèces forestières du pays. Parmi ces impacts figurent le dépérissement des peuplements forestiers, la prolifération de parasites et d’insectes ravageurs, l’intensification des feux de forêt et la récurrence des sécheresses. Ces phénomènes perturbent non seulement les écosystèmes forestiers, mais affectent également l’agriculture, avec des prévisions annonçant une baisse de la production de blé et d’orge pouvant atteindre 15 % dans les régions du sud subhumide. Plus largement, ces transformations compromettent les services écosystémiques essentiels.

La discussion explore également la fiabilité des prévisions climatiques, obtenues grâce à la superposition de huit modèles de circulation générale, soulignant leur rôle clé dans l’analyse des impacts futurs.

Réf. : Meliho, M., Orlando, C.A. & Dallahi, Y. Spatiotemporal modeling of the potential impact of climate change on shifts in bioclimatic zones in Morocco. Environ Monit Assess 196, 907 (2024). https://doi.org/10.1007/s10661-024-13077-0