SNP-based genetic diversity of a network of germplasm banks to establish a core collection for the tropical fruit Hancornia speciosa - Tree Genetics & GenomesHancornia speciosa is a tropical fruit and an important food resource native to Brazil. Its fruits, commercialized in natura or as a frozen pulp or ice cream, are an outstanding source of vitamins C, E, folates, and carotenoids. Despite its economic relevance, the species is still exploited in an extractive manner by harvesting natural populations, and no commercial varieties are available. A network of germplasm banks has been established from seeds and vegetative material collected in different regions throughout the Brazilian Atlantic Forest and Cerrado biomes. Nonetheless, resources are limited to maintain and evaluate all germplasm accessions for plant breeding. We used SNP markers generated by DArTSeq to assess the genetic diversity and population structure of 508 individual plant accessions conserved across three germplasm banks of H. speciosa and proposed a core collection for the species to be targeted for phenotypic characterization efforts. Significant genetic differentiation was found among the germplasm banks (Fst 0.221), with moderate genetic diversity and substantial inbreeding within each one, likely resulting from a Wahlund effect due to within-bank substructure as genetic entries were sampled from disjunct populations. A structure analysis assigned most of the germplasm accessions to two genetic groups, although some admixed individuals were observed. A core collection of 138 accessions (27.11%) was proposed, covering 98% of the currently conserved genetic diversity in the germplasm network. Although the proposed core collection provides a solid representation of the currently conserved genetic diversity for breeding, our results indicate that additional sampling of natural populations not yet surveyed should be pursued. Seasonal Variations in Seed Viability and Vigor of Hancornia speciosa Under Osmoprotective Storage Conditions - Tropical Plant BiologyStorage of desiccation-tolerant seeds is one of the most effective germplasm conservation strategies; however, various species from tropical and subtropical humid forests have seeds that are sensitive to desiccation, recalcitrant seeds, making conservation a challenge. Recalcitrant seeds deteriorate during storage due to high respiration rates and metabolic activity, and protocols employing osmoprotective solutions aim to minimize those effects to maintain seed viability for a longer period. Hancornia speciosa, a fruit tree considered a priority for research in Brazil, is a desiccation-sensitive species of biannual harvest. Thus, the objective of this study was to assess the physiological parameters of viability, vigor, and enzymatic activity of H. speciosa seeds of two harvest seasons, stored in an osmoprotective solution. Germination percentage, water content, electrical conductivity, shoot, root, and seedling length, peroxidase concentration, and heat-resistant protein concentration were all determined for seeds collected during the summer and winter harvests. In addition, gene sequences were explored through gene ontology using Blast analysis to identify the biological and molecular processes associated with enzymatic action during storage. Summer-collected seeds performed better in terms of viability and vigor, with the highest development of shoot, root, and seedling length. The summer-harvest seeds had an initial germination of 80% and maintained a 15% germination rate until 90 days of storage. The seeds collected in the winter had lower initial germination and vigor; however, improved in those parameters during storage in the protective solution, with an increase of 12.5% in germination rate after 90 days. H. speciosa seeds harvested in the summer or winter and stored in the osmoprotective solution remain viable for up to 90 days. The solution has an osmopriming effect on low-vigor seeds, increasing viability and vigor, and the summer-harvest seeds are recommended for storage in the osmoprotective solution. Peroxidase and heat-resistant proteins are active during storage in the solution; the regulation of the expression of these enzymes should be investigated further. Geno-phenotypic diversity in a natural population of Hancornia speciosa Gomes: implications for conservation and improvement - Genetic Resources and Crop EvolutionHancornia speciosa Gomes is native tree to South America, and its fruits are a source of income for communities and the food industry. The reduction of natural occurrence areas of H. speciosa, the absence of a sustainable management plan conservation and breeding programs, threaten its natural populations. Therefore, the purpose of this study was to evaluate the phenotypic variability of fruits, seeds, and seedlings and to estimate the genetic diversity. The main goal is to provide information for the conservation and breeding programs of the species. Measurable variables of fruits, seeds, and seedling; and genetic diversity was estimated by ISSR markers. Among fruits, 53.21% had a longitudinal diameter from 27.5 to 35 mm and 63.15% had a transversal diameter from 24.5 to 35 mm. The average seed biometry was 9.98 mm, 8.21 mm, and 3.97 mm, for length, width and thickness respectively. The length of seedlings shoots varied from 3.0 to 8.5 cm, roots from 4.0 to 15.8 cm and dry mass from 80 to 103 mg seedling−1. The genetic parameters estimated were He = 0.40, I = 0.50, Na = 2.0, Ne = 1.71 and similarity of 55.29%. The population has high phenotypic variability of fruits, seeds and seedlings, and genetic diversity. There is potential for use of this population in the enrichment process for the restoration of natural populations. 
