Plants exposed to abiotic stresses such as drought, salinity, or extreme temperatures produce excessive amounts of harmful molecules known as reactive oxygen species (ROS). These molecules can damage proteins, cellular membranes, and DNA. To maintain cellular homeostasis, plants have developed enzymatic antioxidant systems, among which superoxide dismutases (SODs) play a key role. These enzymes catalyze the conversion of ROS into less toxic compounds. Based on the metal cofactor involved, SODs are classified into three main groups: Cu/ZnSOD, FeSOD, and MnSOD.
In this study, the researchers carried out a comprehensive analysis of the argan tree genome to identify and characterize genes encoding SODs. In total, nine SOD genes were identified and classified into three groups according to the metal cofactor involved. This classification was confirmed through analyses of their gene structures, evolutionarily conserved protein sequences essential for enzymatic function, as well as phylogenetic relationships with SODs from other plant species. In addition, analysis of the regulatory regions of these genes revealed the presence of several cis-regulatory elements associated with stress responses, suggesting a potential role of SOD genes in the adaptation of the argan tree to unfavorable environmental conditions.
Finally, 36 pairs of specific primers were designed to facilitate the analysis of gene expression in future experiments. Their efficiency and specificity were evaluated through in silico analyses, indicating satisfactory performance for subsequent applications.
Overall, this study provides a solid foundation for a better understanding of the role of SOD genes in the argan tree. These findings could ultimately contribute to the development of more stress-tolerant plants capable of better withstanding drought, salinity, and other environmental constraints.
Ref. Chahidi M., El Faqer A., Rabeh K. & Belkadi B., 2025 - Genome-wide survey of superoxide dismutase (SOD) genes in Argania spinosa L., an endemic tree species. Discover Plants (2025) 2:362 – https://doi.org/10.1007/s44372-025-00379-x
Posted by Jean-Paul Peltier.
Using a metabolomic approach, this study aims to identify metabolites present in the argan tree and to detect biomarkers associated with water stress in two ecotypes adapted to contrasting environmental conditions. Understanding which metabolites and metabolic pathways are mobilized in response to drought provides an essential scientific basis for targeting truly effective adaptation mechanisms.
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
Posted by Jean-Paul Peltier.
This bibliometric analysis aims to provide an overview of current scientific knowledge on the argan tree. Using four keywords (arganeraie, arganier, Argania spinosa, and oil), combined with Boolean operators (AND, OR, NOT), the Web of Science and Scopus databases were explored. The study period was limited to 1992–2024, as publications prior to 1992 were too few to be meaningful.
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
Posted by Jean-Paul Peltier.
The study presents new data on the occurrences of species of the genus Oenothera in Morocco, highlighting the identification challenges due to the strong morphological resemblance between taxa. For the first time, Oenothera laciniata is reported in the country, while the presence of Oenothera indecora and Oenothera drummondii is confirmed in the provinces of Kénitra and Tétouan, respectively. It is noteworthy that the latter species had previously been confused with Oenothera biennis. These three taxa of American origin, rare in Morocco, have been observed in coastal sandy habitats. Furthermore, it is shown that Oenothera lindheimeri, a species cultivated for ornamental purposes, occasionally escapes from cultivation areas. To facilitate accurate identification, this article provides detailed morphological descriptions, accompanied by illustrations, a comparison with related species, and an updated dichotomous key for the genus Oenothera in Morocco.
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
Posted by Jean-Paul Peltier.
This study addresses the systematic position of Nepeta nepetoides within the family Lamiaceae. To clarify its phylogenetic placement, molecular analyses were performed using several markers representing different genomic compartments: four chloroplast DNA markers (ycf1, the spacers ycf1–rps15, trnL–trnF, and rpl32–trnL), two nuclear ribosomal DNA markers (ITS and ETS), and a low-copy nuclear gene (PPR-AT3G09060). These markers, commonly employed in phylogenetic investigations of vascular plants, are particularly informative for resolving relationships among closely related species and genera.
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).
Pitardia nepetoides Batt. ex Pit. is hereby reinstated, its lectotype is designated, and Pitardia caerulescens Maire and Pitardia gracilis Andr. are treated as synonyms.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
Posted by Jean-Paul Peltier.
Last modified on Friday, January 9, 2026 at 16h20.