Societal Impact Statement Crop wild relatives (CWR) are plant taxa closely related to crops and are a source of high genetic diversity that can help adapt crops to the impacts of global change, particularly to meet increasing consumer demand in the face of the climate crisis. CWR provide vital ecosystem services and are increasingly important for food and nutrition security and sustainable and resilient agriculture. They therefore are of major biological, social, cultural and economic importance. Assessing the extinction risk of CWR is essential to prioritise in situ and ex situ conservation strategies in Mesoamerica to guarantee the long‐term survival and availability of these resources for present and future generations worldwide. Summary Ensuring food security is one of the world's most critical issues as agricultural systems are already being impacted by global change. Crop wild relatives (CWR)—wild plants related to crops—possess genetic variability that can help adapt agriculture to a changing environment and sustainably increase crop yields to meet the food security challenge. Here we report the results of an extinction risk assessment of 224 wild relatives of some of the world's most important crops (i.e. chilli pepper, maize, common bean, avocado, cotton, potato, squash, vanilla and husk tomato) in Mesoamerica—an area of global significance as a centre of crop origin, domestication and of high CWR diversity. We show that 35% of the selected CWR taxa are threatened with extinction according to The International Union for Conservation of Nature (IUCN) Red List demonstrates that these valuable genetic resources are under high anthropogenic threat. The dominant threat processes are land use change for agriculture and farming, invasive and other problematic species (e.g. pests, genetically modified organisms) and use of biological resources, including overcollection and logging. The most significant drivers of extinction relate to smallholder agriculture—given its high incidence and ongoing shifts from traditional agriculture to modern practices (e.g. use of herbicides)—smallholder ranching and housing and urban development and introduced genetic material. There is an urgent need to increase knowledge and research around different aspects of CWR. Policies that support in situ and ex situ conservation of CWR and promote sustainable agriculture are pivotal to secure these resources for the benefit of current and future generations.

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Crop wild relatives (CWR) intra- and interspecific diversity is essential for crop breeding and food security. However, intraspecific genetic diversity, which is central given the idiosyncratic threats to species in landscapes, is usually not considered in planning frameworks. Here, we introduce an approach to develop proxies of genetic differentiation to identify conservation areas, applying systematic conservation planning tools that produce hierarchical prioritizations of the landscape. It accounts for: (i) evolutionary processes, including historical and environmental drivers of genetic diversity, and (ii) threat processes, considering taxa-specific tolerance to human-modified habitats, and their extinction risk status. Our analyses can be used as inputs for developing national action plans for the conservation and use of CWR. Our results also inform public policy to mitigate threat processes to CWR (like crops living modified organisms or agriculture subsidies), and could advise future research (e.g. for potential germplasm collecting). Although we focus on Mesoamerican CWR within Mexico, our methodology offers opportunities to effectively guide conservation and monitoring strategies to safeguard the evolutionary resilience of any taxa, including in regions of complex evolutionary histories and mosaic landscapes.

Amaranth can help to decrease the problems of food, malnutrition and health of the human population, as it provides energy, protein, vitamins and minerals and is also a natural source of lysine, a rare amino acid in other cereals. However, when stored for use as seeds, they suffer a relatively rapid deterioration, which is mainly reflected in low germination. Osmotic conditioning or "priming" is a treatment that can improve the germination capacity of the seeds, once they have been subjected to deterioration. In this work, an osmotic conditioning experiment was carried out with the objective of increasing the germination percentage in amaranth seeds accessions that are conserved at the National Center of Genetic Resources (CNRG) of INIFAP. The seeds of four amaranth genotypes were hydrated in five KNO3 solutions for 2 h, followed by a 24 h drying period at 25 °C. Subsequently, these seeds were tested for germination. The results showed that the germination was increased with osmotic conditioning using KNO3 solutions, thereby the seed deterioration was reverted. Also, the genotype had an effect on the germinative behavior of the seeds.

The seed anatomy of eight species of ornamental cacti from the Chihuahuan desert was described, germplasm in the process of long-term conservation in the Germplasm Bank of the National Center for Genetic Resources of INIFAP; different qualitative, quantitative and pseudo-qualitative aspects were tested for the characterization of the seed, likewise it was supported with an X-ray equipment. The shape of the seed was varied as well as the size, probably associated with the ecological conditions in which species are distributed; X-rays provide important information on the development and condition of the embryo, however, it is not indicative of the viability of the seed.