A prioritised inventory of crop wild relatives and wild harvested plants of Tunisia

Genet Resour Crop Evol https://doi.org/10.1007/s10722-021-01340-z (0123456789().,-volV) (0123456789().,-volV) RESEARCH ARTICLE A prioritised inventory of crop wild relatives and wild harvested plants of Tunisia Ridha El Mokni . Giulio Barone Gianniantonio Domina . Nigel Maxted . Shelagh Kell . Received: 3 November 2021 / Accepted: 29 December 2021 Ó The Author(s) 2022 Abstract An inventory of crop wild relatives (CWR) and wild harvested plants (WHP) occurring in Tunisia, based on the integration of the last available floristic checklists, is presented. The taxa were prioritised according to economic value of the related crop, potential for crop improvement, threat status, endemism, inclusion in the ITPGRFA (Annex I) and average annual contributions to dietary energy (kilocalories) per capita per day by applying a scoring system based on 4 priority levels. Of a total of 2912 taxa belonging to the Tunisian Flora, 2504 CWR and/ or WHP (86% of the total), from 143 families and 686 genera, were identified, 2445 of which are CWR and 847 are WHP. In detail, 1654 are solely CWR and 59 are WHP only, whereas 788 are both CWR and WHP. The final priority list for active conservation includes 1036 CWR (43% of the total CWR taxa), with 139 taxa rated as high priority, 660 medium priority and 237 low priority. The final priority list for WHP is composed of 344 taxa and includes eight high priority, 254 medium priority and 82 low priority taxa. Our results confirm Tunisia as a hotspot of CWR and WHP diversity in the Mediterranean area. The inventory here proposed provides the basis for the development and implementation of a more targeted national CWR/ WHP conservation strategy for Tunisia. Keywords Crop wild relative
Wild harvested plants
Plant genetic resources
Food security
Conservation
Ethnobotanical use Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/ s10722-021-01340-z. R. El Mokni Laboratory of Botany and Plant Ecology (SNA-214), Department of Life Sciences, Faculty of Sciences of Bizerte, University of Carthage, 7021 Jarzouna, Bizerte, Tunisia G. Barone (&)
G. Domina Department of Agricultural, Food and Forest Sciences (SAAF), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy e-mail: R. El Mokni Laboratory of Silvo-Pastoral Resources, Silvo-Pastoral Institute of Tabarka, University of Jendouba, BP. 345, 8110 Tabarka, Tunisia N. Maxted
S. Kell School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK R. El Mokni Laboratory of Botany, Cryptogamy and Plant Biology, Faculty of Pharmacy of Monastir, University of Monastir, Avenue Avicenna, 5000 Monastir, Tunisia 123 Genet Resour Crop Evol Introduction Crop wild relatives (CWR) are wild plant species closely related to cultivated species of socio-economic value, such as those providing food, fodder, industrial materials, ornamentals, and biofuels (Maxted et al. 2006). CWR play a central role for breeding purposes due to their potential or actual ability to supply beneficial genetic traits for crop improvement (Harlan and de Wet 1971; Maxted et al. 2006, 2010). The Mediterranean region is a centre of diversity for wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), olive (Olea europaea L.), carrot (Daucus carota L.), cabbages (Brassicaceae) and other major food crops. In this area, some native plants host useful traits that can improve the cultivation of their related crops, such as Brassica insularis Moris, a SW Mediterranean endemic that occurs in coastal habitats, which confers resistance to the fungal pathogen Leptosphaeria maculans (Sowerby) P.Karst. in hybrids with B. oleracea (Mithen and Lewis 1988), or Aegilops ventricosa Tausch, which is used in providing resistance to numerous pests and diseases in common wheat (e.g., cyst nematode, leaf rust, stem rust) (Vincent et al. 2013). Additionally, CWR, as components of natural and semi-natural ecosystems, together with other wild species play a role in ecosystem functioning and in broader environmental sustainability and the maintenance of ecosystem services (FAO 2019a). In the frame of a more sustainable, low-input agriculture (Crespo-Herrera and Ortiz 2015; Duru et al. 2015), CWR often represent an under-exploited source of genes for ensuring food security (FAO 2006, 2009a). Furthermore, global challenges, such as climate change and a continuous rise in the human population, are posing a huge threat to biodiversity, affecting both CWR and wild harvested plants (WHP)—undomesticated species typically harvested from the wild by local people. Consequently, potential loss in beneficial and useful traits (Hajjar and Hodgkin 2007; Castañeda-Álvarez et al. 2016; Dempewolf et al. 2017) suitable for granting everyone access to nutritious and safe food, is emerging as a major concern, together with the awareness that protecting biodiversity and ensuring food security are part of a single agenda (Godfray 2011). Food security is pursued by several means and, among them, by the development of new varieties resistant to diseases, pests, or environmental stresses, such as extreme 123 temperatures, drought, and flooding, that require less inputs for their cultivation. Many crop varieties are being replaced with stress tolerant varieties to ensure yield stabilization and continuity of cultivation in altered environments due to climate change, soil degradation or pollution (Mammadov et al. 2018). Crop improvement can be obtained by using existing crop agrobiodiversity (Jacobsen et al. 2015) but also broader-based diversity can be introgressed through the introduction of traits from their wild relatives, which are adapted to diverse habitats and have not passed through the genetic bottleneck of domestication (Vollbrecht and Sigmon 2005; Hajjar and Hodgkin 2007). The conservation of these plant genetic resources (PGR) is therefore a priority for agriculture and environmental sustainability because it can help to increase sustainable crop production (Reeves et al. 2016) and reduce negative impacts on future food security. WHP have for millennia provided the primary source of fuel, construction material and food, and even today they are a valid supplement to the diet and medicine for peoples of the Mediterranean Basin (Vavilov 1926; Harlan and de Wet 1971; Morales et al. 2013; Landucci et al. 2014; Maxted and Vincent 2021). According to the World Health Organization, 65% of the world population rely on plant derived products as sources of therapeutic agents for their health care (Fabricant and Farnsworth 2001). Lavania (2005) estimated that nearly 6000 species of plants are exploited for their traditional, herbal, or medicinal characteristics. There is also a clear link between medicinal plants and food as demonstrated by the Mediterranean diet (Willett 2006; Sofi et al. 2010) where leafy vegetables are collected to add variety and nutrition to the diet (...truncated)