The neglected and underutilized plants (NUPs) have never been mainstreamed by researchers, politicians and stakeholders for sustainable exploitation in the ornamental-horticultural sector. This study focused on 399 local endemic plants of three Mediterranean regions (Crete, Mediterranean coast-Rif of Morocco, Tunisia), with the aim to develop a new scheme for their multifaceted ornamental-horticultural evaluation facilitating their sustainable exploitation. The methodological scheme was developed within three multidisciplinary co-creative workshops by experts and was adjusted by end-users. The developed scheme uses point and weighted scoring of several attributes relevant to biological and ornamental-horticultural characteristics and concerns three ranking levels: (i) ornamental-horticultural potential (general or subsector-specific; 20 attributes), (ii) sustainable exploitation feasibility (12 attributes) and (iii) readiness timescale (after gap and SWOT analyses) in creating value chains in short-, medium- or long-term. The analysis of the data illustrated two example-cases of already achieved sustainable exploitation with established value chains; outlined the prospects for sustainable exploitation of 18 and 23 local endemic NUPs in short-term and medium-term, respectively; and identified 86 taxa with reachable possibilities in the long-term. The proposed multifaceted evaluation scheme can be applied for the valorisation of NUPs in other areas and may help to define priorities and to identify opportunities and gaps for their sustainable exploitation.

Medicinal-aromatic plants (MAPs) are important sources for the development of new valuable products of interest to human and animal health, and are also used as ornamentals for the horticulture industry. However, the increased global demand and the uncontrolled exploitation of these plants constitute a threat to their sustainability. To date, few scientific investigations have focused on MAPs valorization and their domestication. The purpose of this study was to evaluate for the first time the medicinal-cosmetic potential of 399 local endemic Mediterranean plants confined to Crete (223 taxa), the Mediterranean coast-Rif of Morocco (94), and Tunisia (82). The new methodological scheme was developed by experts through three multidisciplinary co-creative workshops and was adjusted by end-users to point-scoring of nine attributes evaluating the potential of the targeted neglected and underutilized plants (NUPs) in the medicinal-cosmetic sector. The results were demonstrated as percentage of the maximum possible score. These assessments were further linked and discussed with respect to feasibility and readiness timescale evaluations for sustainable exploitation of the focal NUPs. A great diversity of local endemic NUPs (30 taxa, 11 families) were associated with interesting medicinal-cosmetic properties (>35% up to 94.44%). Among them, 8 taxa showed the highest medicinal-cosmetic potential (>55% of maximum possible score), half of which are threatened with extinction. Although ex-situ conservation efforts and applied research work are needed to safeguard and unlock the full potential of the local endemic NUPs evaluated herein, the proposed multifaceted evaluation scheme revealed that some local endemic NUPs of the studied regions can be sustainably exploited in short- or medium-term, following successful examples of Cretan NUPs e.g., Origanum dictramnus. The sustainable exploitation of high scored taxa of the studied regions can be fastened through targeted species-specific research bridging extant research gaps and facilitating conservation and stakeholder attraction.

The domestication of wild-growing plants, including cultivation and fertilization protocols, is able to alleviate the ecological risks posed by the uncontrolled harvesting of range-restricted local endemic plants. In this field study focused on Verbascum arcturus, a vulnerable local endemic of Crete (Greece), the effect of two kinds of fertilization applied by two methods (foliar/root) was investigated. The foliar application included conventional or integrated nutrient management (INM) fertilization. Root application included the application of conventional fertilizers, biostimulants, or INM with biostimulants. Several properties of plant growth, physiology and nutrition were determined. The results showed that fertilization treatment affected neither leaf color and shape nor plant growth, morphology, dry mass partitioning or nutrient content. However, both kinds of foliar-applied fertilization enhanced Zn and B in leaves and soil-applied biostimulant increased leaf Ca. Considering both chlorophyll and antioxidant compounds’ content, foliar application of the INM fertilizers, as well as soil application of the conventional fertilizers or biostimulants, could be considered as accepted options. This study reports for the first time an assessment of the total phenolic and flavonoids content evidenced in V. arcturus and encourages the use of fertilization in promoting the herbal antioxidant profile without compromising visual quality or yield. The findings of this study could be considered as a documented contribution toward the sustainable exploitation of V. arcturus.

Conservation and sustainable exploitation of threatened endemic plants with medicinal and/or horticultural/ornamental value can be achieved through the development of effective propagation protocols. After unveiling the bioclimatic preferences of Carlina diae (Asteraceae) with geographic information systems (GIS), four propagation trials were conducted using seeds of this endangered local Cretan endemic for in vivo and in vitro germination, as well as seasonal vegetative propagation trials (softwood cuttings) and micropropagation (nodal explants). Seed germination was accomplished at a level of 77–90% in vivo (30 days) and 96% in vitro (10 days) using an MS medium with 2.9 μM gibberellic acid (GA₃). The optimum treatments for cuttings’ rooting were 1000 and 2000 ppm indole-3-butyric acid (IBA) (11–16 roots, 2–3 cm long, 100% rooting) within 40 days in mist. In vitro shoot propagation exhibited a 2.8 proliferation rate after six successive subcultures on an MS medium with 2.9 μM GA₃. Both ex vitro rooting and acclimatization were successful in 40 days, with 96% microshoot rooting and an equal survival rate. The GIS-facilitated effective species-specific propagation protocols developed in this study can consolidate the perspective of successful re-introduction of ex situ-raised material of C. diae into wild habitats and may serve its sustainable exploitation for high-added value ornamental products.

In the frame of the sustainable use of neglected and underutilized phytogenetic resources, and along with numerous studies in Abies spp. due to the innate conservation value of fir forests, this research focused on the Moroccan endemic fir, Abies marocana. The aim was triple-fold: to assess its potential and dynamics in economic sectors for sustainable exploitation; to determine the ecological conditions in which the species naturally thrives; and to find the appropriate requirements for its successful seed germination. We sourced multifaceted evaluations for three economic sectors performed in three levels, using 48 attributes and eight criteria from previous studies of our own, and the relevant species-specific assessments are overviewed herein in detail. The species’ ecological profile was constructed using Geographical Information Systems (GIS) and open access data (Worldclim). Seed germination trials were performed to examine the effect of cold stratification (non-stratified, one- and two-months stratified seeds), the influence of four temperatures (10 °C, 15 °C, 20 °C, and 25 °C), and interactions thereof in relation to germination percentage (GP) and mean germination time (MGT). The experiments showed that the interaction of cold stratification and germination temperature has a strong effect on the GP and MGT of A. marocana seeds. A detailed GIS-derived ecological profile of the focal species was created in terms of precipitation and temperature natural regimes, enabling the interpretation of the seed germination results. The multifaceted evaluations reveal an interesting potential of the Moroccan fir in different economic sectors, which is mainly compromised due to extant research gaps, unfavorable conditions, and low stakeholder attraction. The findings of this study fill in extant research gaps, contribute to in situ and ex situ conservation strategies, and can facilitate the sustainable exploitation of this emblematic local endemic plant of northern Morocco.