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Lima bean (Phaseolus lunatus L.), one of the five domesticated Phaseolus bean crops, shows a wide range of ecological adaptations along its distribution range from Mexico to Argentina. These adaptations make it a promising crop for improving food security under predicted scenarios of climate change in Latin America and elsewhere. In this work, we combine long and short read sequencing technologies with a dense genetic map from a biparental population to obtain the chromosome-level genome assembly for Lima bean. Annotation of 28,326 gene models show high diversity among 1917 genes with conserved domains related to disease resistance. Structural comparison across 22,180 orthologs with common bean reveals high genome synteny and five large intrachromosomal rearrangements. Population genomic analyses show that wild Lima bean is organized into six clusters with mostly non-overlapping distributions and that Mesomerican landraces can be further subdivided into three subclusters. RNA-seq data reveal 4275 differentially expressed genes, which can be related to pod dehiscence and seed development. We expect the resources presented here to serve as a solid basis to achieve a comprehensive view of the degree of convergent evolution of Phaseolus species under domestication and provide tools and information for breeding for climate change resiliency. Lima bean is an important crop for improving food security in Latin America and elsewhere. Here, the authors assemble its genome, conduct population genomics analysis using genotyping-by-sequencing data, and identify differentially expressed genes between two pod developmental stages. [ABSTRACT FROM AUTHOR]

Despite the evolutionary, ecological and economic importance of introgression between a domesticated species and its wild relatives in centers of diversity and domestication, the role of traditional farmers in this process has received limited attention. In the Yucatan Peninsula, the region of Mexico that has the greatest amount of domesticated varieties of Lima bean, wild populations grow sympatrically with conspecific varieties, allowing the Mayan farmer to act directly on introgressed seed. We used 11 microsatellite loci to assess levels of introgression in three wild-domesticated complexes of Lima bean from the Yucatan Peninsula and analyze its impact on the genetic diversity of this crop. structure and InStruct analyses showed similar results. The Instruct analysis indicated that the complex with the lowest level of introgression was one where the farmer actively selected against wild plants and introgressed seed. In contrast, the complex with the highest level of introgression was one where the farmer has been consciously selecting a weedy morphotype for 15 years and has already incorporated it into his diet. Genetic diversity of the domesticated pool was higher in the complex with the higher level of introgression. This study showed that farmers have an important role in limiting or favoring the wild to crop introgression and influencing the levels of genetic diversity in their domesticated pool. Only when traditional farmers' knowledge is taken into account can we correctly understand the dynamics, generation and maintenance of genetic diversity of the landraces in the centers of diversity and domestication. [ABSTRACT FROM AUTHOR]

Traditional farming communities frequently maintain high levels of agrobiodiversity, so understanding their agricultural practices is a priority for biodiversity conservation. The cultural origin of agave spirits (mezcals) from west-central Mexico is in the southern part of the state of Jalisco where traditional farmers cultivate more than 20 landraces of A gave angustifolia Haw. in agroecosystems that include in situ management of wild populations. These systems, rooted in a 9000-year-old tradition of using agaves as food in Mesoamerica, are endangered by the expansion of commercial monoculture plantations of the blue agave variety (A. tequilana Weber var. Azul), the only agave certified for sale as tequila, the best-known mezcal. Using intersimple sequence repeats and Bayesian estimators of diversity and structure, we found that A. angustifolia traditional landraces had a genetic diversity (HBT = 0.442) similar to its wild populations (HBT = 0.428) and a higher genetic structure (θB = 0.405; θB =0. 212). In contrast, the genetic diversity in the blue agave commercial system (HB = 0.118) was 73% lower. Changes to agave spirits certification laws to allow the conservation of current genetic, ecological and cultural diversity can play a key role in the preservation of the traditional agroecosystems. [ABSTRACT FROM AUTHOR]

The purpose of this study is to perform a meta-analysis of the state of knowledge of ICT-based education in Mexico and Latin America in the last decade. Prior to seeking information, general lines of knowledge application and categories were defined. The results indicate that studies are mostly focused on virtual learning resources and their contribution to education. Similarly, it was found that 80% of studies are qualitative, with quantitative or mixed studies accounting for only a fifth of work on the subject. In Mexico, 46% of research addresses higher education; this figure is 62% in Latin America. Gaps were found in knowledge generation in parents' digital skills, student training in ICT competency, educational outreach with businesses, and disability education. [ABSTRACT FROM AUTHOR]

• Low genetic diversity was found in Huaya India (Melicoccus oliviformis) in its putative domestication center. • Genetic groups found in Huaya India from the Maya Lowlands of Mexico appear to behave as a continuum from wild to domesticated individuals. • Wild-domesticated genetic continuum is a consequence of a high genetic flow and the management of the species by the Maya people. Currently, some species of Sapindaceae are important fruit crops worldwide. The Huaya India (Meliccocus oliviformis , Sapindaceae) is a neglected Neotropical fruit tree consumed locally in the Maya Lowlands of Mexico, where it exists in both wild and domesticated forms. Our objective was to evaluate the genetic diversity of the Huaya India in its possible domestication area and thus generate knowledge that serves as the basis for a commercial management. A total of 450 individuals collected from 15 natural vegetation sites and 15 Maya villages, were characterized using nine microsatellite loci and population genetics approaches were applied. STRUCTURE, Neighbor-Joining and PCoA analyses suggested the existence of three main groups: 1) one composed by 14 natural vegetation sites, 2) one integrated by 10 Maya villages plus one natural vegetation site, 3) one composed by five Maya villages. At the species level, genetic differentiation was high (F ST = 0.562) and gene flow was low (Nm = 0.395); between genetic groups, differentiation was low and gene flow was high. Genetic diversity was low at the level species (H E = 0.19) and higher in the group composed for only natural vegetation sites. When we considered only two groups (natural vegetation sites vs Maya villages) to explore a possible bottleneck as a consequence of human management, the natural vegetation sites showed higher, and significant, genetic diversity (H E = 0.231) than the Maya villages (H E = 0.152). This study can serve as a basis to develop management strategies for Huaya India in the Maya Lowlands of Mexico, but without compromising its conservation. [ABSTRACT FROM AUTHOR]

Due to the increase in demand for food production worldwide, the cultivation of improved varieties is used as a strategy in order to maximize production. The improved Maradol papaya variety was introduced to the Yucatan Peninsula (YP), Mexico, the Mesoamerican diversity area of papaya, in the 1990s. The domesticated and wild papaya belong to the same species (Carica papaya L.), which promotes gene flow from crops to their wild relatives, threatening the genetic diversity of wild papaya populations in the region. In this study, we used a population genomic approach to evaluate the impact of domesticated-to-wild gene flow on the genetic structure and diversity of wild papaya in the YP. We used 2054 SNP markers for 227 wild individuals from 15 collection sites and 127 domesticated individuals from 13 Maradol papaya plantations. We found, (a) the presence of individuals that may be the result of a hybridization process between wild and domesticated papaya; (b) a higher genetic diversity in the wild group (H E  = 0.18) in comparison to the domesticated group (H E  = 0.09); and (c) low migration rates from domesticated to wild plants (m = 0.005). The domesticated-to-wild gene flow in C. papaya can have a negative effect on the genetic diversity and adaptive potential of wild populations from this region. The conservation of crop wild relatives should be a priority since they are part of various ecological processes and are considered natural reservoirs of genetic diversity for crops., Competing Interests: Declarations. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Pouteria sapota is known for its edible fruits that contain unique carotenoids, as well as for its fungitoxic, anti-inflammatory and anti-oxidant activity. However, its genetics is mostly unknown, including aspects about its genetic diversity and domestication process. We did high-throughput sequencing of microsatellite-enriched libraries of P. sapota, generated 5223 contig DNA sequences, 1.8 Mbp, developed 368 microsatellites markers and tested them on 29 individuals from 10 populations (seven wild, three cultivated) from Mexico, its putative domestication center. Gene ontology BLAST analysis of the DNA sequences containing microsatellites showed potential association to physiological functions. Genetic diversity was slightly higher in cultivated than in the wild gene pool (HE = 0.41 and HE = 0.35, respectively), although modified Garza-Williamson Index and Bottleneck software showed evidence for a reduction in genetic diversity for the cultivated one. Neighbor Joining, 3D Principal Coordinates Analysis and assignment tests grouped most individuals according to their geographic origin but no clear separation was observed between wild or cultivated gene pools due to, perhaps, the existence of several admixed populations. The developed microsatellites have a great potential in genetic population and domestication studies of P. sapota but additional sampling will be necessary to better understand how the domestication process has impacted the genetic diversity of this fruit crop.