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BACKGROUND: The COVID-19 pandemic has exacerbated existing healthcare disparities among American Indian/Alaska Native (AI/AN) populations rooted in historical traumas and systemic marginalization. METHODS: This study conducted at a single Indian Health Service (IHS) clinic in central Michigan evaluates two educational interventions for enhancing COVID-19 knowledge and attitudes in a sample AI/AN population. Utilizing a pre/post-intervention prospective study design, participants received either a video or infographic educational intervention, followed by a survey assessing their COVID-19 knowledge and attitudes. RESULTS: The results indicate significant improvements in knowledge and attitudes post-intervention, with both modalities proving effective. However, specific factors such as gender, political affiliation, and place of residence influenced COVID-19 attitudes and knowledge, emphasizing the importance of tailored interventions. CONCLUSIONS: Despite limitations, this study highlights the critical role of educational interventions in addressing vaccine hesitancy and promoting health equity within AI/AN communities. Moving forward, comprehensive strategies involving increased Indian Health Service funding, culturally relevant interventions, and policy advocacy are crucial in mitigating healthcare disparities and promoting health equity within AI/AN communities.

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When colonizing new ranges, plant populations may benefit from the absence of the checks imposed by the enemies, herbivores, and pathogens that regulated their numbers in their original range. Therefore, rates of plant damage or infestation by natural enemies are expected to be lower in the new range. Exposing both non-native and native plant populations in the native range, where native herbivores are present, can be used to test whether resistance mechanisms have diverged between populations. Datura stramonium is native to the Americas but widely distributed in Spain, where populations show lower herbivore damage than populations in the native range. We established experiments in two localities in the native range (Mexico), exposing two native and two non-native D. stramonium populations to natural herbivores. Plant performance differed between the localities, as did the abundance of the main specialist herbivore, Lema daturaphila. In Teotihuacán, where L. daturaphila is common, native plants had significantly more adult beetles and herbivore damage than non-native plants. The degree of infestation by the specialist seed predator Trichobaris soror differed among populations and between sites, but the native Ticumán population always had the lowest level of infestation. The Ticumán population also had the highest concentration of the alkaloid scopolamine. Scopolamine was negatively related to the number of eggs deposited by L. daturaphila in Teotihuacán. There was among-family variation in herbivore damage (resistance), alkaloid content (scopolamine), and infestation by L. daturaphila and T. soror, indicating genetic variation and potential for further evolution. Although native and non-native D. stramonium populations have not yet diverged in plant resistance/constitutive defense, the differences between ranges (and the two experimental sites) in the type and abundance of herbivores suggest that further research is needed on the role of resource availability and adaptive plasticity, specialized metabolites (induced, constitutive), and the relationship between genealogical origin and plant defense in both ranges.

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Biological invasions pose global threats to biodiversity and ecosystem functions. Invasive species often display a high degree of phenotypic plasticity, enabling them to adapt to new environments. This study examines plasticity to water stress in native and invasive Opuntia ficus-indica populations, a prevalent invader in arid and semi-arid ecosystems. Through controlled greenhouse experiments, we evaluated three native and nine invasive populations. While all plants survived the dry treatment, natives exhibited lower plasticity to high water availability with only a 36% aboveground biomass increase compared to the invasives with a greater increase of 94%. In terms of belowground biomass, there was no significant response to increased water availability for native populations, but plants from the invasive populations showed a 75% increase from the dry to the wet treatment. Enhanced phenotypic plasticity observed in invasive populations of O. ficus-indica is likely a significant driver of their success and invasiveness across different regions, particularly with a clear environmental preference towards less arid conditions. Climate change is expected to amplify the invasion success due to the expansion of arid areas and desertification. Opuntia ficus-indica adapts to diverse environments, survives dry spells, and grows rapidly in times of high-water supply, making it a candidate for increased invasion potential with climate change.

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Interactions between wild, feral, and domestic animals are of economic and conservation significance. The pigeon Columba livia is a synanthropic species in a feral form, but it also includes the rare Rock Dove. Columba livia is an important player at the wild-domestic interface, acting as a carrier of avian diseases, and the feral form threatens Rock Doves with extinction via hybridisation. Despite its abundance, little is known about drivers of disease prevalence in C. livia, or how disease and hybridisation represent synergistic threats to Rock Doves. We focused on infection by the parasite Trichomonas, first collating prevalence estimates in domestic and free-living populations from relevant studies of C. livia. Second, we characterised variation in the diversity and prevalence of Trichomonas among three C. livia populations in the United Kingdom: a feral, a Rock Dove, and a feral-wild hybrid population. Across multiple continents, free-living pigeons had lower Trichomonas infection than captive conspecifics, but the effect was weak. Environmental factors which could impact Trichomonas infection status did not explain variation in infection among populations. Among the British populations, strain diversity varied, and there was lower parasite prevalence in Rock Doves than feral pigeons. Individual infection status was not explained by the available covariates, including hybrid score and site. The drivers of Trichomonas prevalence are unclear, perhaps due to idiosyncratic local-scale drivers. However, given the population-level variation in both infection prevalence and introgressive hybridisation, the potential combined effects could accelerate the extinction of the Rock Dove. Further study of the synergistic effects of multiple types of biotic interactions at the wild-feral-domestic interface is warranted, especially where vagile, globally distributed and superabundant animals are involved.

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AbstractEctothermic species are dependent on temperature, which drives many aspects of their physiology, including locomotion. The distribution of the native populations of Xenopus laevis is characterized by an exceptional range in latitude and altitude. Along altitudinal gradients, thermal environments change, and populations experience different temperatures. In this study, we compared critical thermal limits and thermal performance curves of populations from the native range across an altitudinal gradient to test whether optimal temperatures for exertion differ depending on altitude. Data on exertion capacity were collected at six different temperatures (8°C, 12°C, 16°C, 19°C, 23°C, and 27°C) for four populations spanning an altitudinal gradient (60, 1,016, 1,948, and 3,197 m asl). Results show that the thermal performance optimum differs among populations. Populations from cold environments at high altitudes exhibit a lower optimal performance temperature than populations from warmer environments at lower altitudes. The ability of this species to change its optimal temperature for locomotor exertion across extremely different climatic environments within the native range may help explain its exceptional invasive potential. These results suggest that ectothermic species capable of adapting to broad altitudinal ranges may be particularly good at invading novel climatic areas, given their ability to cope with a wide range of variation in environmental temperatures.

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The last decade has witnessed growing calls for the return of individual research results. Prior work in genetic studies has shown that individual, contextual, and cultural factors influence participants' preferences for individual research results. There is a gap in knowledge about participants' views about other types of results, specifically those lacking clinical significance. This study investigates the perspectives of 1587 mothers enrolled in the Northern Plains Environmental Influences on Child Health Outcomes (ECHO) Program. Participants were presented with hypothetical scenarios to determine their perceived value of individual research results based on result type and the ability to interpret them within a normative context. Irrespective of the result type, participants attributed higher perceived value to results that were well understood than results of unknown significance.

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An ongoing controversy in invasion biology is the prevalence of colonizing plant populations that are able to establish and spread, while maintaining limited amounts of genetic variation. Invasive populations can be established through several routes including from a single source or from multiple introductions. The aim of this study was to examine genetic diversity in populations of Mimulus guttatus in the United Kingdom, where the species is considered invasive, and compare this diversity to that in native populations on the west coast of North America. Additionally, we looked at diversity in non-native populations that have not yet become invasive (naturalized populations) in eastern North America. We investigated population structure among populations in these three regions and attempted to uncover the sources for populations that have established in the naturalized and invasive regions. We found that genetic diversity was, on average, relatively high in populations from the invasive UK region and comparable to native populations. Contrastingly, two naturalized M. guttatus populations were low in both genetic and genotypic diversity, indicating a history of asexual reproduction and self-fertilization. A third naturalized population was found to be a polyploid Mimulus hybrid of unknown origin. Our results demonstrate that M. guttatus has likely achieved colonization success outside of its native western North America distribution by a variety of establishment pathways, including those with genetic and demographic benefits resulting from multiple introductions in the UK, reproductive assurance through selfing, and asexual reproduction in eastern North America, and possible polyploidization in one Canadian population.

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Sweet briar (Rosa rubiginosa) belongs to the group of wild roses. Under natural conditions it grows throughout Europe, and was introduced also into the southern hemisphere, where it has efficiently adapted to dry lands. This review focuses on the high adaptation potential of sweet briar to soil drought in the context of global climatic changes, especially considering steppe formation and desertification of agricultural, orchard, and horticultural areas. We provide a comprehensive overview of current knowledge on sweet briar traits associated with drought tolerance and particularly water use efficiency, sugar accumulation, accumulation of CO2 in intercellular spaces, stomatal conductance, gibberellin level, effective electron transport between photosystem II and photosystem I, and protein content. We discuss the genetics and potential applications in plant breeding and suggest future directions of study concerning invasive populations of R. rubiginosa. Finally, we point out that sweet briar can provide new genes for breeding in the context of depleting gene pools of the crop plants.

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BACKGROUND: As the older Indigenous population in the United States expands, there is a growing demand for programs to address age-related needs. Although Title VI of the OAA provides culturally responsive strategies to support elders through home- and community-based nutrition services, these programs have not been the subject of a national evaluation; our study is the first. METHODS: We conducted a mixed-methods study to assess the impact of the Title VI programs on elders. We used quantitative data from a national survey of Indigenous elders (n = 1175) and qualitative data collected through interviews (n = 36) and focus groups (18, n = 161) with a subgroup of elders receiving services. We compared outcomes for social and cultural connectedness and physical and mental well-being for different subgroups within our sample of elders based on elders' use of Title VI services and the level of services provided to these elders. Results were adjusted for community characteristics. RESULTS: Elders receiving Title VI services had significantly fewer hospitalizations and falls per year (hospitalizations: 0.9 vs. 1.2, p < 0.05; falls: 1.0 versus 1.1, p < 0.05) and significantly more social and cultural engagements per month (social engagements: 92.6% vs. 75.6%, p < 0.05; cultural practices: 78.8% vs. 64.8%, p < 0.05) compared with elders who did not participate in Title VI services. These findings were confirmed by our qualitative data. CONCLUSIONS: Our findings highlight the vital role that the Title VI program plays in promoting elders' overall health and well-being through decreased hospitalizations and falls and increased connectedness.

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Indigenous Peoples in the United States have been experiencing disproportionate impacts of COVID-19. American Indian and Alaska Native persons are more likely to be infected, experience complications, and die from coronavirus. Evidence suggests that Indigenous persons have 3.5 times the incidence rate of non-Hispanic/Latinx whites. Unfortunately, this is likely a gross underestimate because of a lack of reliable and accurate COVID-19 data for American Indian and Alaska Native populations. Multiple factors contribute to poor data quality including the lack of Indigenous representation in the data and rampant racial misclassification at both the individual and group levels. The current pandemic has shed light on multiple pre-existing issues related to Indigenous data sovereignty in data collection and management. We discuss the importance of centring Indigenous data sovereignty in the systemic efforts to increase COVID-19 data availability and quality. The federal and state governments must support and promote Tribes' rights to access data. Federal and state governments should also focus on bolstering their data availability and quality for aggregated data on AIAN populations and for providing disaggregated Tribal data to Tribes. Given the pivotal moment in the United States with ongoing and parallel pandemics of coronavirus and racism, we urge demographers and population scientists to reflect on the role of structural racism in data, data collection and analysis.

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BACKGROUND: The establishment of non-native populations of threatened and legally protected species can have many implications for the areas where these species have been introduced. Non-native populations of threatened species have the potential to be exploited and therefore the subject of legal protection, while conversely, if they have become invasive in their introduced range, there is the likelihood that population control will be carried out to reduce abundance and negative impacts associated with introduced species. From both a legal and invasive species monitoring standpoint, it is important to know how many individuals are present. METHODS AND RESULTS: Short tandem repeats (STRs) were developed for the hog deer, an endangered species that was introduced following European settlement to Victoria, Australia using Illumina MiSeq sequencing technology. These markers were combined with previous STRs characterised for hog deer to create a 29-plex identification system. A total of 224 samples were genotyped across the population in Victoria, and further analyses of null allele frequencies, deviation from Hardy-Weinberg equilibrium, and the removal of monomorphic or low amplifying markers resulted in a final marker panel of 15 loci. Despite low values for number of alleles at each locus (2-4), probability of identity showed sufficient discrimination power, with an average probability of identity at 2.94 × 10-6, and a probability of sibling identity of 8.9 × 10-4 across all sites. CONCLUSIONS: It is feasible to create an informative DNA profiling system that can distinguish between individuals for applications in both wildlife forensic and population control research.

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Studies on relationships between psychosocial factors and health among North African (NA) women are scarce. This research investigated the self-perceived psychosocial well-being of NA women by a structured questionnaire and anthropometric survey examining the possible explanatory variables of their mental health in comparison to a sample of NA migrants. The association of endogenous stress, psychological well-being, discomfort, and quality of life with migrant/non-migrant status, demographic characteristics, and adiposity indices was examined. Moreover, the internal consistency of the questionnaire was tested using Cronbach's alpha. A sample of 228 women living in Tunis and Casablanca participated in a survey in Tunisia and Morocco. According to multiple regression models, migrant/non-migrant status was the best explanatory variable of well-being and quality of life, marital status, educational level and the number of children were explanatory variables of discomfort and endogenous stress. Among anthropometric variables, central adiposity was a significant explanatory variable of well-being. The comparison with women who migrated mainly from Morocco and Tunisia to Italy (NA migrants) exhibited higher weight status and central adiposity in NA migrants. The perceived stress and discomfort were the same in the two groups; the migrants, despite reporting lower psychological well-being, presented a higher quality of life than residents. Our findings emphasise the potential to promote monitoring of the psychosocial health of NA women, planning effective interventions.

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Introducción: La enterobiosis es una de las principales infecciones intestinales del mundo. Objetivo: Determinar los factores asociados a la infección por Enterobius vermicularis en niños de dos comunidades nativas Ese'Eja en Madre de Dios, Perú. Métodos: Estudio transversal analítico. Se trabajó con niños (77) de 1 a 11 años durante los meses de febrero a marzo de 2014. Para diagnosticar la enterobiosis se usó el test de Graham. Las manifestaciones clínicas fueron evaluadas por un médico y los factores asociados mediante una encuesta aplicada a los padres de los niños evaluados. Se usó estadística descriptiva y analítica, se utilizaron razones de prevalencia crudas y ajustadas con un IC 95 por ciento se consideró p< 0,05 como significativo. Resultados: La prevalencia de enterobiosis fue de 32,47 por ciento (25). Los factores asociados (RP e IC 95 por ciento) en el análisis bivariado fueron onicofagia 2,1 (1,1-3,9), chuparse los dedos 5,4 (2,1-2,7), uñas largas 7 (2,6-18,6), intercambio de ropa 2,3 (1,1-3,7), cambio de ropa interior 3,3 (1,8-5,9), uso de calzado 7 (2,6-18,4), juego con tierra 6,9 (1,7-27,3), juego con mascotas 6,4 (2,1-19,7), lavado de manos antes de comer 7,9 (3,6-17,1), lavado de manos después de comer 1,9 (1,7-3,66), 6 o más personas en la casa 3,9 (1,9-7,9), disposición de excretas a campo abierto 3,3 (1,7-6,2) y el menor nivel socioeconómico 2,6 (1,3-5,4). No hubo asociaciones en el análisis multivariado. Conclusiones: Existe una alta prevalencia de enterobiosis en la población estudiada y los factores de riesgo son similares a los antecedentes locales. Urge hacer programas de prevención y promoción de salud respecto al tema para reducir este problema(AU)

Introduction: Enterobiasis is one of the main intestinal infections worldwide. Objective: Determine the factors associated to Enterobius vermicularis infection in children from two native Ese'Eja communities in Madre de Dios, Peru. Methods: An analytical cross-sectional study was conducted in February-March 2014 of 77 children aged 1-11 years. Enterobiasis diagnosis was based on Graham's test. Clinical manifestations were evaluated by a physician, whereas associated factors were determined through a survey applied to the parents of the children studied. Use was made of descriptive and analytical statistical analysis, and crude and adjusted prevalence ratios with a CI of 95 percent. A p value of 0.05 was considered significant. Results: Enterobiasis prevalence was 32.47 percent (25). The associated factors (PR and CI 95 percent) in the bivariate analysis were onychophagia 2.1 (1.1-3.9), finger sucking 5.4 (2.1-2.7), long nails 7 (2.6-18.6), exchanging clothes 2.3 (1.1-3.7), changing underwear 3.3 (1.8-5.9), wearing shoes 7 (2.6-18.4), playing with earth 6.9 (1.7-27.3), playing with pets 6.4 (2.1-19.7), handwashing before eating 7.9 (3.6-17.1), handwashing after eating 1.9 (1.7-3.66), six or more people in the household 3.9 (1.9-7.9), feces disposal in open areas 3.3 (1.7-6.2) and a lower socioeconomic level 2.6 (1.3-5.4). Multivariate analysis did not find any association. Conclusions: Enterobiasis prevalence is high in the population studied, and the risk factors are similar to the local antecedents. It is urgent to develop health prevention and promotion programs about the topic to reduce this problem(AU)

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Studies on the peopling of South America have been limited by the paucity of sequence data from Native Americans, especially from the east part of the Amazon region. Here, we investigate the whole exome variation from 58 Native American individuals (eight different populations) from the Amazon region and draw insights into the peopling of South America. By using the sequence data generated here together with data from the public domain, we confirmed a strong genetic distinction between Andean and Amazonian populations. By testing distinct demographic models, our analysis supports a scenario of South America occupation that involves migrations along the Pacific and Atlantic coasts. Occupation of the southeast part of South America would involve migrations from the north, rather than from the west of the continent.

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During plant invasions, exotic species have to face new environmental challenges and are affected by interacting components of global change, which may include more stressful environmental conditions. We investigated an invasive species of New Zealand grasslands, commonly exposed to two concomitant and limiting abiotic factors-high levels of ultraviolet-B radiation and drought. The extent to which Verbascum thapsus may respond to these interacting stress factors via adaptive responses was assessed in a greenhouse experiment comprising native German plants and plants of exotic New Zealand origins. Plants from both origins were grown within four treatments resulting from the crossed combinations of two levels of UV-B and drought. Over twelve weeks, we recorded growth, morphological characteristics, physiological responses and productivity. The results showed that drought stress had the strongest effect on biomass, morphology and physiology. Significant effects of UV-B radiation were restricted to variables of leaf morphology and physiology. We found neither evidence for additive effects of UV-B and drought nor origin-dependent stress responses that would indicate local adaptation of native or exotic populations. We conclude that drought-resistant plant species might be predisposed to handle high UV-B levels, but emphasize the importance of setting comparable magnitudes in stress levels when testing experimentally for antagonistic interaction effects between two manipulated factors.

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Among the traits whose relevance for plant invasions has recently been suggested are genome size (the amount of nuclear DNA) and ploidy level. So far, research on the role of genome size in invasiveness has been mostly based on indirect evidence by comparing species with different genome sizes, but how karyological traits influence competition at the intraspecific level remains unknown. We addressed these questions in a common-garden experiment evaluating the outcome of direct intraspecific competition among 20 populations of Phragmites australis, represented by clones collected in North America and Europe, and differing in their status (native and invasive), genome size (small and large), and ploidy levels (tetraploid, hexaploid, or octoploid). Each clone was planted in competition with one of the others in all possible combinations with three replicates in 45-L pots. Upon harvest, the identity of 21 shoots sampled per pot was revealed by flow cytometry and DNA analysis. Differences in performance were examined using relative proportions of shoots of each clone, ratios of their aboveground biomass, and relative yield total (RYT). The performance of the clones in competition primarily depended on the clone status (native vs. invasive). Measured in terms of shoot number or aboveground biomass, the strongest signal observed was that North American native clones always lost in competition to the other two groups. In addition, North American native clones were suppressed by European natives to a similar degree as by North American invasives. North American invasive clones had the largest average shoot biomass, but only by a limited, nonsignificant difference due to genome size. There was no effect of ploidy on competition. Since the North American invaders of European origin are able to outcompete the native North American clones, we suggest that their high competitiveness acts as an important driver in the early stages of their invasion.

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BACKGROUND: For populations with high rates of trauma exposure yet low behavioural health service use, identifying and addressing trauma in the primary care setting could improve health outcomes, reduce disability and increase the efficiency of health system resources. OBJECTIVE: To assess the acceptability and feasibility of a screening, brief intervention and referral to treatment (SBIRT) process for trauma and symptoms of posttraumatic stress disorder (PTSD) among American Indian and Alaska Native people. We also examine the short-term effects on service utilization and the screening accuracy of the Primary Care Posttraumatic Stress Disorder Screen. METHODS: Cross-sectional pilot in two tribal primary care settings. Surveys and interviews measured acceptability among patients and providers. Health service utilization was used to examine impact. Structured clinical interview and a functional disability measure were used to assess screening accuracy. RESULTS: Over 90% of patient participants (N = 99) reported the screening time was acceptable, the questions were easily understood, the right staff were involved and the process satisfactory. Ninety-nine percent would recommend the process. Participants screening positive had higher behavioural health utilization in the 3 months after the process than those screening negative. The Primary Care Posttraumatic Stress Disorder Screen was 100% sensitive to detect current PTSD with 51% specificity. Providers and administrators reported satisfaction with the process. CONCLUSIONS: The SBIRT process shows promise for identifying and addressing trauma in primary care settings. Future research should explore site specific factors, cost analyses and utility compared to other behavioural health screenings.

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Resumen La diversidad del maíz en México se fundamenta por la presencia de 59 a 64 razas; Tamaulipas como estado productor contribuye a mantener la variabilidad entre razas, especialmente en las regiones aisladas. La reserva de la Biósfera "El Cielo" localizada en una región montañosa, que comprende los municipios de Jaumave, Ocampo, Gómez Farías y Llera de Canales, ha sido escasamente estudiada, a pesar de que existen riesgos de degradación o extinción de poblaciones nativas de maíz, por factores como cambios de uso de suelo y fenómenos naturales. El objetivo de este trabajo fue analizar la diversidad morfológica de poblaciones nativas de maíz de la Reserva de la Biósfera "El Cielo". Durante los meses de febrero, marzo y abril del 2016, se realizaron recolectas de maíces nativos en los municipios que comprenden la reserva. El tamaño de la muestra varió, entre 20 y 30 mazorcas de cada población, y de estas, se eligieron 10 mazorcas para registrar variables cuantitativas y cualitativas. Se utilizaron los métodos multivariados de análisis de componentes principales y conglomerados. El 62.45 % correspondió a la variación total, la cual fue explicada por los dos primeros componentes principales, y las variables con mayor contribución a la variación fueron longitud de mazorca, número de granos por hilera, peso de mazorca, peso y volumen de 100 granos, diámetro de mazorca y de olote, número de hileras por mazorca y la relación diámetro/longitud de mazorca. En las poblaciones nativas de maíz que aún se cultivan en la Reserva de la Biósfera "El Cielo", se encontró amplia diversidad morfológica de mazorca, así como variación en la combinación de colores de grano y olote, lo que sugiere que las poblaciones nativas representan un amplio potencial como acervo genético y reservorio de genes.

Abstract The diversity of maize in Mexico is based on the presence of breeds that range from 59 to 64 varieties. Tamaulipas is a corn-producing state that contributes to sustain this enormous variation of breeds, especially in isolated regions. The biosphere ecological reserve "El Cielo" is located in a mountainous region, which comprises Jaumave, Ocampo, Gómez Farías and Llera de Canales municipalities. This region has been scarcely studied in spite of the degrada tion or extinction risks of native populations of maize due to factors such as changes in land use and natural phenomena. The objective of this work was to analyze the morphologic diversity of native maize varieties of "El Cielo" biosphere ecological reserve. Native maize harvests were collected in the municipalities that comprise the reserve during the months of February, March and April of 2016. The sample size ranged between 20 and 30 cobs of each variety, out of this sample 10 cobs were selected in order to register quantitative and qualitative variables. A multivariate analysis method of main components and conglomerates was used. Results show that 62.45 % of the samples were correspondent with total variation, which was explained by the first two main compo nents. The variables with greater contribution to the variation were cob length, number of grains per row, cob weight, weight and volume of 100 grains, cob diameter, number of rows per hob and the relation of diameter/length in each cob. The native maize populations that are still cultivated at the biosphere ecological reserve "El Cielo" there was a wide morphological diversity of cob, as well as variation in the com bination of grain and corncob color. This sug gests that native populations possess a substantial potential as a gene pool and gene reservoir.

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In northeast Argentina, different Amerindian communities share territory and history with settlers, mainly Europeans. Due to miscegenation, the current Argentinean population has a particular structure that can be described through X chromosome variation. The objectives of this study were to describe the variation of 10 X-chromosome short tandem repeats (X-STRs) in urban populations of the Argentinean regions known as Gran Chaco and Mesopotamia, report the forensic parameters of these STRs, and estimate the European and indigenous genetic components in these regions. Population and forensic parameters were estimated for 419 individuals from the analyzed populations, including two indigenous groups, Wichí and Mocoví, previously reported. Population structure was estimated through FST and RST distances and analysis of molecular variance. The indigenous American and European components were assessed with STRUCTURE. X-STRs showed a high level of genetic variability in urban and indigenous populations. Indigenous people of the Gran Chaco region showed significant differentiation from the urban samples (FST = 5.5%) and among themselves (FST = 5.3%). Genetic differentiation among urban groups was almost negligible, except that the population from Misión Nueva Pompeya differed from the rest of the city populations. Forensic parameters indicate that these X-STRs are useful as a complement to paternity tests. The set of 10 STRs could be a good tool for examining population differences.

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ABSTRACT: In the present study, we investigated the influence of social and environmental factors in the genetic diversity of tomato landraces in the South-Central region of Mexico. A total of 30 tomato landraces, collected in 18 villages with different ethnolinguistic affiliations, were analyzed. We reported that the genetic diversity of tomato landraces is associated with the ethnolinguistic group, weather, and soil-type present in the region studied. Our results showed that there are morphological differences between landraces grown by different ethnolinguistic groups; however, there was also evidence of morphological similarities between landraces from groups with different ethnolinguistic affiliations. Finally, different selection criteria, mainly fruit color, size and shape, plays an important role in the phenotypic divergence among landraces grown in different traditional farming systems.

RESUMO: No presente estudo investigamos a relação da afiliação etnolinguística com a diversidade genética de variedades locais de tomate na região Centro-Sul do México. Um total de 30 variedades de tomate, coletadas em 18 aldeias com diferentes afiliações etnolinguísticas, foram analisadas. Verificamos que a diversidade genética das variedades crioulas de tomate está associada ao grupo etnolinguístico presente na região estudada. Nossos resultados mostram que existem diferenças morfológicas entre raças cultivadas por diferentes grupos etnolinguísticos. No entanto, também houve evidências de semelhanças morfológicas entre raças de grupos com diferentes afiliações etnolinguísticas. Finalmente, diferentes critérios de seleção, como, principalmente, cor, tamanho e forma dos frutos, desempenham um papel importante na divergência fenotípica entre as variedades crioulas cultivadas em diferentes sistemas agrícolas tradicionais.