Extinction risk of Mesoamerican crop wild relatives

Crop wild relatives (CWR) are plant taxa closely related to crops and a source of high genetic diversity that can help adapt the impacts global change, particularly meet increasing consumer demand in face climate crisis. CWR provide vital ecosystem services increasingly important for food nutrition security sustainable resilient agriculture. They therefore major biological, social, cultural economic importance. Assessing extinction risk is essential prioritise situ ex conservation strategies Mesoamerica guarantee long-term survival availability these resources present future generations worldwide. Reducing environmental impact agriculture simultaneously feeding an exponentially growing human population change (Godfray et al., 2010; Vermeulen 2012) one world's most pressing challenges. The effects on already observed (Banerjee 2018; Brás 2021; Gourdji 2015; Huq Jaramillo 2011; Läderach 2017) expected worsen without mitigation adaptation actions (Barros & Field, 2014; Campbell 2016; Dawson Lobell Porter 2014) with overall crop yield declines between 3% 10% predicted each degree warming (Challinor 2014). Changes varietal production resulting from or through synergistic other drivers caused by land use (e.g. soil degradation loss pollination services) include reduced diversity, variable yields increased vulnerability emerging pathogens pests (FAO, Foley 2005; Groenen, Keneni 2012; Ricketts 2008; Scheffers 2016). stresses such as drought, salinity flooding, well consequent changes prevalence diseases, while ensuring nutritional value yields, will be key responding (Campbell FAO, 2008, 2010, Ford-Lloyd Guarino Lobell, Maxted Nabhan 2020; Ortiz, Zamir, 2001). For example, Mexican potato Solanum demissum has been used extensively breeding programs against late blight (Ross, 1986). Likewise, S. pinnatisectum cardiophyllum show resistance Colorado beetle (Chen 2004). Thus, rich variability changing conditions found (CWR)—wild species crops—including their ancestors, which persist wide variety habitats under heterogeneous conditions, have not passed domestication bottleneck (Maxted 1997; Tanksley McCouch, 1997). Therefore, it so far recognised they undergone evolutionary processes intervention sustain breadth Flores-Hernández Hawkes 2000; Mariac 2006; Kell, 2009; van de Wouw 2001; Vaughan, 1994). However, there ethnobotanical evidence suggests some artificial selection could exerted CWR. Recent studies indicate range management practices resources, including Mesoamerican CWR, probably were sustained over long periods time (Casas Luna-Ruiz Levis 2018). importance achieving (Ford-Lloyd Harlan, 1976; Hoyt, 1988; McCouch 2013; Prescott-Allen Prescott-Allen, 1990). Food become integral element both agricultural sectors reflected international policy frameworks, United Nations Sustainable Development Goals (SDG). Aichi Biodiversity Target 13 Convention Biological Diversity (CBD) Strategic Plan 2011–2020 called maintenance safeguarding (CBD, 2010), also highlighted Post 2020 Framework 8 9; CBD, 2019). 2.5 SDG 2 (Zero Hunger) calls maintain seeds, cultivated plants farmed domesticated animals (United Nations, 2015). centre origin, Vincent, Vavilov, 1935; Vincent An estimated 8% (Vavilov, 1935), maize, squash, chilli pepper, bean, avocado, vanilla cotton, region around 10,000 5000 years ago (Clement Hummer Hancock, Piperno Smith, 2012). process results manipulation genotypes satisfy requirements still part (Hajjar Hodgkin, 2007). Further, cultivation involved Caballero, 1995; Perry Flannery, Accordingly, because many considered due food, nutritional, values (CONABIO 2019a, 2019b; Shiferaw Wei 2012), identified priority conduct (Castañeda-Álvarez There good reasons believe proportion occurring threatened extinction. harbours 3000 endemic flowering yet had lost more than 80% its original native vegetation cover beginning 21st century (Mittermeier 2011). annual deforestation was calculated 395,000 ha 2005 2010 (Elizondo 2015), making 36 biodiversity hotspots (Rodríguez Olivet Asquith, suffer severe (BID CEPAL, Thomas 2016), holds adaptive solutions should conserved functional genomics; Mastretta-Yanes Although national SEMARNAT-2010-NOM-059; DOF, 2010) assessments completed groups (Goettsch IUCN, Rivers, 2017), targeted. We here first assessment occur within Mesoamerica. focus nature threats affecting them discuss policies implemented strengthen conservation. included six staple foods common husk tomato squash typically ancestral multicrop milpa system. remains main means subsistence direct consumption trade surplus smallholder farmers (Bellon Lopez-Ridaura Zizumbo-Villarreal Colunga-GarcíaMarín, 2010). study focused mainly (Figure 1a; Kirchhoff, 1960), includes central southern Mexico, Guatemala, El Salvador Honduras. In instances, areas outside Aridamerica (Nabhan 2020) northern Mexico analyses evaluate complete genera strictly distributed Mesoamerica, thus accounting full extent geographic taxon 1b,c). A list approximately (i.e. species, subspecies, varieties subpopulations; Dataset S1) belonging same genus compiled different sources Acevedo Gasman Azurdia Bellon Perales Aguirre, 2008). 310 (Contreras-Toledo 2018), 105 Guatemala (Azurdia 2011), 50 (Chízmar-Fernández Echeverría 2008) 54 Honduras (Núñez Alvarado, 1995). subset (with exception Tripsacum, tertiary gene pool relative Zea mays) selected following set criteria relevant biological characteristics region, during stakeholder workshop (Methods S1). evaluated according International Union Conservation Nature (IUCN) Red List Categories Criteria (IUCN, expert S2). Information distribution, trends, ecology, actions, reviewed taxon. As this process, maps generated using 28,000 occurrence data points CONABIO, Trust, GBIF, personal databases; Data available IUCN website 2020). These spatial distribution generate richness S3) showing S4). Detailed collated literature observations experts participating coded Threats Classification Scheme (based Salafsky version 3.2 https://www.iucnredlist.org/resources/threat-classification-scheme). Because Threatened Species global, we assessed throughout entire range. total 224 selected: pepper (Capsicum spp.), (Cucurbita cotton (Gossypium avocado (Persea bean (Phaseolus (Physalis (Solanum sect. Petota), maize (Zea spp. Tripsacum spp.) (Vanilla (Table taxonomic groups, all four countries included. case Vanilla, represent less number known globally, (35%) S5) extinction, 7 Critically Endangered (CR), 48 (EN) 16 Vulnerable (VU). Nine Near (NT), 125 Least Concern (LC) 19 Deficient (DD) Vanilla highest 100% (eight taxa) threatened, followed (Gossypium) 92% (12 taxa), (Persea) 60% (9 44% (four 33% taxa, respectively 2). 20 km × grid cells located states Jalisco Oaxaca 31 28 1b). Other medium richness, ranging 15 27 is, western Nayarit Michoacán, State, City, Puebla Veracruz east (CR, EN VU) NT cell eastern state seven Persea, two Phaseolus (Cell 1, Figure 1c; Table 1). Seven contain each. Four (Cells 3–6, 1c), together harbour Persea Physalis Cucurbita Capsicum Another hotspot borders Hidalgo Solanum, Phaseolus, five 2, Finally, area bordering Chiapas Vanilla. (one Capsicum, Solanum) parts departments Chimaltenango, Sacatepéquez, Escuintla Jalisco, Puebla, 9–15, 1c). Note mentioned above, only 32 out 80 represented CR cribbiana perennis) Also, might populations hence (Tobón al. unpublished). Threat (version 3.2) 134 (60% taxa). threat activities responsible degradation, destruction and/or impairment biodiversity; 65% (87) systems associated intensity vary, but cattle ranching occupy majority lands. Invasive problematic next threat, reported 38% (51) threats, resource (threats consumptive “wild” organisms thereof, populations, any biotic component actual potential humanity, removing system destroying them) 32% (43) salient residential commercial development disturbing 25% (34) weather impacting 21% (28; Across frequent proximate ultimate factor enabling contributing process; varied. Smallholder affects (43), 31% (42 possibly frequency extent, generally lower agro-industrial farming sometimes evosystem (Faith housing urban (22%, 29 introduced material (16%, 21 (15%, farming, small-scale incidental logging form habitat shifting alteration, 14% (19 3). differ group. (71% (54%) (46%) affected ranching, (75%) (67%) driver (100%) farming. Gossypium tourism recreation overcollection (100%). (50%), diseases driver, (70%) nonnative invasive 12% (26) unknown, corresponded categorised DD (13 LC (10 (three 28% (62 no significant threats; true wide-ranging taxa. cases latter exposed stressors linked wider declines. at subspecific level recorded level, those subpopulations) avoid duplication. Thirty three percent directly indirectly utilised. percentage utilised (91%) (65%) S3). end (48%) corresponding Physalis, 26% 11% 4). Research (an indirect use), improvement, second (46% 39% being 23% 16% 22% improvement representing 62%, 19% 6% Cucurbita, uses medicinal, forage ornamental. across (96%), (83%) (74%) S4), lowest (17%, 18% 25%, respectively). Gossypium, 9, uses, With 35% best estimate; Methods S5), levels comparable conifers (34% threatened; cacti (31% Goettsch twice regional European (Bilz where (n = 572; threatened. unevenly 1b) 1c) Transition Zone (Morrone, Nearctic-Neotropic biotas overlap great geological ecological complexity (Halffter, 1978; Rzedowski, 1978). transition zone encompasses convergence Trans-Mexican Volcanic Belt (TMVB), Sierra Madre Oriental, Occidental del Sur. TMVB renowned (Mastretta-Yanes Rodríguez Sosa Villaseñor mountains Central America belong forests, contains richest Earth, terms endemism (Espinosa Mittermeier Within mountains, often cloud forest habitat—a naturally fragmented community which, despite covering relatively small geographical area, extraordinary divergence among lineages complex history (Ornelas Venkatraman Cloud forests habitats. 1% 73% degraded (INEGI, 2003, Up 99% disappear 2080 clearing (Ponce-Reyes disappearing rate recent decades (Pope Protected play role protecting cryptic (Bosland Gonzalez, 2000); therefore, protection remnants (CONABIO, exceptions perennis, do Instead, tend richness. This approaches aiming maximise focusing harbouring numbers useful certain instances additional required ensure narrowly accounted for. addition, consider analysis, particular representation (Kell Riordan Nabhan, much rest biodiversity, large (Maxwell intensified last decades, tendency convert diverse, traditional agroecosystems dependent inorganic fertilisers, pesticides fungicides mechanisation (Harvey contrast adapted disturbance even thrive perturbed tolerated fostered, inadvertently Delgado-Salinas dasycarpus abundant edge arable lands (Delgado-Salinas, Similarly, radicans (EN), scarlet runner coccineus annuum var. glabriusculum C. frutescens fostered fields (Aragón Cuevas, Sánchez la Vega, Contrastingly, weeds destroyed argyrosperma correspond ssp. sororia; Castellanos Morales 2019; Aguirre Dugua Switches weed tolerant industrial agriculture, herbicide pesticide prevalent, severely (populations glabriusculum), aridum) teosinte luxurians). Conversion natural into lands, extensive pristine areas. lanceolatum pallescens grow highly pine-oak forest, perennis converted plantations (Sánchez 2019) order supply markets (de Fuente Stevens, (Figures S1 Notably, impacted potentially change. alien grasses Megathyrsus maximus Rottboellia cochinchinensis) 3), taxa: intermedium, T. maizar zopilotensis armourianum, insular whose feral goats cats (Wegier 2017). Introduced threatens and, lesser hybridisation genetically modified facilitates erosion, modifies plant-insect interactions aridum, Wegier, G. hirsutum, Vázquez-Barrios 2021) causes habit Cruz-Reyes efforts frame release living (Acevedo 2016) protect (DOF, MAGA, region. third prevalent Though 75% 53% use, taxon) vary groups. All targeted collection, driving wild. contrast, P. cinerascens), albescens) lanceolatum) unintentionally wood harvesting result (species mortality) (i.e., conversion degradation; 5). may hold climatic exempt themselves (Jarvis Redden 2015); S2), altering droughts While multiple others appear specific pools instance, davidsonii, harkenssii hirsutum) social unsettlement illegal grown unsafe research implement populations. Here individual 3) that, conjunction, diverse suite our useful, taxon-specific information, tools map would valuable planning purposes. Nineteen (8.5% assessed) grouped S1), meaning information insufficient 8.7%). low attributable point Such enormous numerous academic, governmental nongovernmental organisations collect, compile analyse make available, CONABIO's National System Global Facility (GBIF) (Troudet records remain undigitised scattered, collections few listed uncertainty longicaulis). 17 DD, constraint lack accurate status trend effects. Some sessilis guerreroense) collected 78 ago, type localities leptophyllus, latecorollata, parvianthera sessilis). palmata, rufescens lesteri) reportedly specimens likely distributions, sizes/trends 6) assess risk. Field locate remaining individuals urgently needed armourianum tehuacanensis, Possibly Extinct. Given here, need floristic inventories, identify risk, Equally promote inform establish characterize readily along gradient, occurs (Carrillo-Galván 2020, references therein). needs generation size, ran