Oases play a crucial role in human societies and the conservation of biodiversity, especially in harsh environments like arid zones. They serve as sanctuaries for agrodiversity, preserving diverse agricultural resources under challenging climatic conditions. However, these agroecosystems are becoming increasingly vulnerable to climate fluctuations, droughts, and other environmental changes. Understanding these unique agroecosystems is essential for developing effective strategies to protect them. Agrodiversity serves as a key indicator of the overall health of traditional agroecosystems. To assess the richness and diversity of agrodiversity, field surveys were conducted in six representative oases in southern Morocco. Within each oasis, we interviewed 20 farmers in five ksour. Our findings confirm the widespread practice of polyculture and reveal significant diversity among the oases. A total of 55 crops were identified, consisting of 183 varieties. Specifically, the oasis of Tata employed 42 crops, Alnif had 41 crops, Guelmim had 38 crops, Aoufouss had 32 crops, Rich had 29 crops, and Zagora had 28 crops. The profiles of varieties clearly distinguish between ksour and oases, highlighting the unique identities of each oasis. The modernization of farming practices is influenced by factors such as farm size, plot fragmentation, dispersal, and irrigation methods. However, its consequences are concerning. There is a risk of losing agrodiversity and compromising the food security of local populations. The shift from household consumption crops to cash crops has negative implications for the availability of diverse and nutritious food. Moreover, modernization often leads to increased water consumption, further straining the already limited water resources in these oases.

The carob tree (Ceratonia siliqua L.) is a significant fruit tree in the Mediterranean region with cultural, biological, and ecological importance. Despite its importance, intraspecific trait variability (ITV) in carob trees has been largely overlooked in previous studies. Understanding ITV and its relationship with environmental conditions is crucial for conservation and breeding programs. In this study, we investigated the variability of carob pod and seed-related traits across different ecological scales in 25 studied populations in Morocco. Significant differences in morphological traits were observed between carob populations at various ecological levels, and pod-related traits exhibited greater variability than seed traits. Correlation analysis revealed strong associations between carob morphological traits and environmental conditions, with altitude and aridity index playing an influential role. The aridity gradient was strongly related to changes in pod size, seed number, and size, as well as seed yield. Our findings highlight an important ITV reaching 45% at the intra-population level, 36.5% at the inter-geographic level, and 30% at the inter-population level. Overall, this study contributes valuable insights into the ecology and adaptation of carob trees, emphasizing the importance of considering intraspecific variability when studying this remarkable species. This knowledge is critical for addressing the challenges posed by climate change and human activities on the long-term survival and ecological functioning of carob populations.

Questions: While globalisation favours intensive yield-maximizing agriculture with cropping practices that entail agrobiodiversity loss, extensive production systems still exist in areas of marginal lands such as in mountainous regions or islands. It is overdue to study such systems, their sustainability and ecology as potential models for decentralized environmentally balanced land-use. For that purpose, we investigated the composition of the wild arable (segetal) flora in traditional thermo- to mesomediterranean cereal-growing agroecosystems of northwestern Morocco. Study area: The Tingitane (Tangier) Peninsula in the Northwest of Morocco. Methods: A sample of 94 relevés was collected in six areas in the foreland of the Rif Mountains. Results: We found 209 species in 150 genera and 41 families, a mean of 22 species per relevé and a Shannon index of 3.04±0.06. A TWINSPAN classification revealed a high level of similarity between the areas, with the plant communities corresponding to the order Brometalia rubenti-tectorum, but also differences in species composition as a result of climatic, soil and land-use effects. Therophytes dominated, but biennial and perennial herbs indicating shallow tillage and fields under fallow were also common. Almost half of the species found were agrestal species (confined to arable fields), and almost a third were apophytes (native species occurring in fields but also in natural habitats). Twenty-nine species (14%) of the segetal flora were regional endemics and six are considered nationally rare. Although there is evidence of recent structural and floristic diversity decline, traditional agroecosystems tend to favour native species including some of particular conservation interest. Conclusions: The traditional agroecosystems of the Rif Mountains fulfil criteria of High Nature Value agriculture but, in view of recent socio-economic change, require support by policy for their maintenance. Taxonomic reference: Euro+Med PlantBase (http://www.europlusmed.org) [accessed 26 Nov 2022]. Syntaxonomic reference: EuroVegChecklist (Mucina et al. 2016). Abbreviations: TWINSPAN = Two Way Indicator Species Analysis.

Moroccan populations of Alnus glutinosa (L.) Gaerth. (Betulaceae) are found at the southern limit of the species’ range and are represented by tetraploid cytotypes with no available pollen data. The objective of this study was to assess the morphological and morphometric variability of the pollen, specifically focusing on pollen diameters and the number of apertures. To achieve this, we sampled 11 populations that are representative of the Moroccan distribution area of this species. We employed a hierarchical sampling design (11 populations, 10 trees per population, and from 30 to 300 pollen grains per tree, depending on the character measured) to examine different levels of variability: interpopulation, intrapopulation, and intraindividual. The results demonstrate that there is no discernible difference in the morphology or size of the pollen among the Moroccan tetraploid populations. However, we observed a high degree of intraspecific variability in pollen morphometric traits, but most of this variability is associated with the intraindividual level.

Environmental cues, such as biotic and abiotic stresses, are limiting factors for plants’ growth and development. In the current context of global change, the vulnerability of plant species to environmental stressors is increasing with the observed and predicted climate changes and anthropogenic pressures. Consequently, understanding plant responses to environmental stresses is a major concern. However, plant species have developed several adaptive mechanisms and strategies to tolerate or resist the stressful conditions found within their environment. In this chapter, we report the effects of different stressful conditions on the emblematic olive tree (Olea europaea L.). The reported responses to biotic and abiotic stressors show that the olive tree exhibits an important level of tolerance and several resistance mechanisms to maintain its physiological process and, therefore, to sustain its growth and development. This chapter provides interesting insights into the olive tree’s importance as a valuable genetic resource for future breeding programs, especially under the current global changes. <!----> <!----> <!----> <!---->

Plant species in Mediterranean ecosystems are expected to exhibit diverse responses to environmental stresses such as climate aridity and challenging soil conditions by adopting various functional strategies. However, intraspecific variability at the local scale has received insufficient attention in the study of CSR strategies. This study aims to evaluate intraspecific variability in leaf traits and CSR strategies of seven woody species growing on ultramafic and non-ultramafic soils in the Beni Bousera region of Northern Morocco. We first conducted a physicochemical analysis to assess differences in soil composition between the two sites. Subsequently, we measured leaf fresh weight, leaf dry weight, and leaf area and calculated CSR strategies for 10 individuals per species. The results revealed significant differences between the two soil types, primarily driven by a moderate serpentine effect characterized by a Ca:Mg ratio <1 in the ultramafic site, along with distinct soil texture. In response to these challenging conditions, we observed substantial intraspecific variability in leaf traits, accompanied by shifts in CSR strategies for certain species. At the ultramafic site, Quercus coccifera adopted an S strategy, while Cistus salviifolius exhibited an S/SC strategy. Lavandula stoechas and Teucrium fruticans displayed notable interindividual variability, whereas Cistus atriplicifolius, Phillyrea latifolia, and Erica arborea maintained consistent strategies across both sites. Our research contributes to the enrichment of CSR databases and highlights the applicability of the CSR strategy framework at the local, intraspecific level, offering a valuable foundation for future ecological studies and plant conservation efforts. Moreover, investigating intraspecific variability in leaf traits and CSR strategies enhances our understanding of plant adaptation mechanisms in extreme environments such as Mediterranean serpentine soils.