ABSTRACT The Myrtaceae family is home to several species of economic and ecological importance, but many are in areas of constant environmental degradation, demanding studies aiming at the conservation status evaluation or other characteristics of interest. One of the widely used tools for these purposes is SSR markers. This study sought to evaluate the transferability of 11 new SSR markers characterized in Eugenia uniflora to 14 different species of the family Myrtaceae. Out of the 11 markers tested, nine were amplified in at least one of the examined species. For seven species, this is the first report of cross-species transfer of SSR markers. These markers may contribute to the characterization of the genetic diversity of the species and planning policies for the conservation and breeding of these genetic resources.

Abstract Plinia phitrantha and P. cauliflora are Myrtaceae species with recognized horticultural and pharmacological potential. Nevertheless, studies on molecular genetics and the evolution of these species are absent in the literature. In this study, we report the complete plastid genome sequence of these species and an analysis of structural and evolutive features of the plastid genome within the tribe Myrteae. The two plastid genomes present the conserved quadripartite structure and are similar to already reported plastid genomes of Myrteae species concerning the size, number, and order of the genes. A total of 69-70 SSR loci, 353 single nucleotide polymorphisms, and 574 indels were identified in P. phitrantha and P. caulifora. Observed evolutive features of the plastid genomes support the development of programs for the conservation and breeding of Plinia. The phylogenomic analysis based on the complete plastid genome sequence of 15 Myrteae species presented a robust phylogenetic signal and evolutive traits of the tribe. Ten hotspots of nucleotide diversity were identified, evidence of purifying selection was observed in 27 genes, and relative conservation of the plastid genomes was confirmed for Myrteae. Altogether, the outcomes of the present study provide support for planning conservation, breeding, and biotechnological programs for Plinia species.

ABSTRACT Plinia species comprise a group of underrated fruit trees native to the South and Central American neotropics. Their fruits have high potential as a nutraceutical food and to the medicinal industry. However, among the 80 accepted species, less than a dozen are cultivated. In this review, the state-of-the-art of the genetic diversity and the techniques of vegetative propagation of Plinia spp. was updated. Therewith, it is intended to encourage further studies for genetically disentangle the taxonomic classification the species, and the development of propagation protocols towards the establishment of commercial plantations. Establishing commercial orchards of Plinia species may open new markets for this fruit crop, but the absence of breeding programs and superior quality seedlings hinder such endeavors. The main outcomes of this study are the need of using molecular approaches for solving the taxonomic uncertainties among Plinia species and micropropagation protocols to overcome the difficulties concerning to the vegetative propagation of this species.

RESUMEN Las especies de Plinia comprenden un grupo subestimado de árboles frutales nativos de los neotrópicos de América del Sur y Central. Sus frutos tienen un alto potencial como alimento nutracéutico y para la industria medicinal. Sin embargo, entre las 80 especies aceptadas, se cultivan menos de una docena. En esta revisión, se actualizó el estado del arte de la diversidad genética y las técnicas de propagación vegetativa de Plinia spp. Con ello, se propondrá impulsar nuevos estudios para dilucidar genéticamente la clasificación taxonómica de la especie y el desarrollo de protocolos de propagación hacia el establecimiento de plantaciones comerciales. El establecimiento de plantaciones comerciales de especies de Plinia spp. puede abrir nuevos mercados para este cultivo de frutas, pero la ausencia de programas de mejoramiento genético y plántulas de calidad superior obstaculizan tales esfuerzos. Los principales resultados de este estudio son la necesidad de utilizar enfoques moleculares para resolver las incertidumbres taxonómicas entre las especies de Plinia y los protocolos de micropropagación para superar las dificultades relacionadas con la propagación vegetativa de esta especie.

RESUMO: Eugenia involucrata DC. é uma espécie florestal com elevado potencial ambiental e econômico. O presente trabalho teve por objetivo quantificar a variabilidade e analisar a estruturação genética em três fragmentos naturais localizados na região central do estado do Rio Grande do Sul, Brasil. Com o emprego de quatro locos microssatélites desenvolvidos para a espécie congênere Eugenia uniflora e usando-se o software GenAlEx 6.5, foram estimados parâmetros de variabilidade genética, para cada loco, e sua partição entre e dentro dos fragmentos. Foram observados altos índices de variabilidade genética (3,67 alelos por loco; HO = 0,815; HE = 0,625; FIS = -0,294), com a maior proporção (93%) distribuída dentro dos fragmentos, sugerindo que os indivíduos estudados são provenientes de uma única população original. O fluxo gênico foi elevado entre os fragmentos, variando de 2,35 a 4,56 migrantes por geração, resultando em baixo índice de diferenciação genética (FST), entre 0,052 a 0,096. Os fragmentos estudados apresentam elevada variabilidade genética, a maior parte distribuída dentro dos próprios remanescentes, e baixa diferenciação genética. Os resultados observados têm repercussões no planejamento de coleta de germoplasma com adaptação local para programas de restauração florestal, assim evitando a implantação de populações com depressão exogâmica.

ABSCTRACT: Eugenia involucrata DC. is a forest species with high environmental and economic potential. The objective of this study was to quantify the genetic variability and analyzed the genetic structure of three natural fragments located in the central region of the Rio Grande do Sul state, Brazil. We used four microsatellite loci developed for the congener species Eugenia uniflora and using GenAlEx 6.5 software, parameters of genetic variability and its partition among and within fragments were estimated for each locus. We observed high levels of genetic variability (3.67 alleles per locus; HO = 0.815; HE = 0.625; FIS = −0.294), most of which (93%) were distributed within the fragments, suggesting that these individuals came from a single original population. Gene flow between fragments was high (2.35 to 4.56 migrants per generation), resulting in low genetic differentiation indexes (FST values ranging from 0.052 to 0.096). The fragments showed high genetic variability, distributed within the remnants themselves, and low genetic differentiation. Our results have repercussions for planning locally adapted germplasm collections for forest restoration programs, thereby avoiding the implantation of populations with an exogamous depression.

ABSTRACT Eugenia uniflora is an American tree species with ecological, agronomical and medicinal importance. However, just few studies have focused on the in vitro propagation and production of secondary metabolites. This study investigated the explant sources and culture conditions for the in vitro callogenesis in E. uniflora towards induction of somatic embryogenesis and production of antioxidant compounds. Nodal segments, leaf sections and root segments from in vitro germinated seeds were used as explants and eight different combinations of auxins (2,4-D or NAA) and cytokinins (BAP or TDZ) were tested for the callus induction. The best callogenic response was observed in nodal segments, followed by leaf sections. Root segments presented comparatively poorer callogenic performance. Calli from nodal segments cultivated in MS medium with NAA (10 µM) + TDZ (5 µM) originated putative pro-embryogenic structures, while the culture in liquid medium using MS supplemented with NAA (10 µM) + TDZ (5 µM) revealed significantly higher content of phenols and flavonoids, as well as higher reducing capacity than the tested treatments and the control (fresh leaves). In summary, the calli obtained from nodal segments revealed competence for somatic embryogenesis induction and development as well as the production of secondary metabolites with pharmaceutical potential.

RESUMEN Eugenia uniflora es una especie arbórea americana de importancia ecológica, agronómica y medicinal. Sin embargo, pocos estudios se han centrado en la propagación y producción in vitro de metabolitos secundarios. Este estudio investigó las fuentes de explantes y las condiciones de cultivo para la callogénesis in vitro en E. uniflora para la inducción de embriogénesis somática y la producción de compuestos antioxidantes. Se utilizaron segmentos nodales, secciones de hojas y segmentos de raíz de semillas germinadas in vitro como explantes y se probaron ocho combinaciones diferentes de auxinas (2,4-D o ANA) y citoquininas (BAP o TDZ) para la formación de callos. La mejor respuesta callogénica se observó en segmentos nodales, seguidos de secciones foliares. Los segmentos de raíz presentaron un rendimiento callogénico comparativamente menor. Los callos de segmentos nodales cultivados en medio de cultivo MS con NAA (10 µM) + TDZ (5 µM) originaron estructuras proembriogénicas putativas, mientras que el cultivo en MS medio líquido con ANA (10 µM) + TDZ (5 µM) reveló un contenido significativamente mayor de fenoles y flavonoides, así como una mayor capacidad reductora que los tratamientos probados y el control (hojas frescas). En resumen, los callos obtenidos de segmentos nodales revelaron competencia para la inducción y el desarrollo de embriogénesis somática, así como para la producción de metabolitos secundarios con potencial farmacéutico.

Abstract Plastomes are very informative structures for comparative phylogenetic and evolutionary analyses. We sequenced and analyzed the complete plastome of Campomanesia xanthocarpa and compared its gene order, structure, and evolutionary characteristics within Myrtaceae. Analyzing 48 species of Myrtaceae, we identified six genes representing ‘hotspots’ of variability within the plastomes (ycf2, atpA, rpoC2, pcbE, ndhH and rps16), and performed phylogenetic analyses based on: (i) the ycf2 gene, (ii) all the six genes identified as ‘hotspots’ of variability, and (iii) the genes identified as ‘hotspots’ of variability, except the ycf2 gene. The structure, gene order, and gene content of the C. xanthocarpa plastome are similar to other Myrtaceae species. Phylogenetic analyses revealed the ycf2 gene as a promissing region for barcoding within this family, having also a robust phylogenetic signal. The synonymous and nonsynonymous substitution rates and the Ka/Ks ratio revealed low values for the ycf2 gene among C. xanthocarpa and the other 47 analyzed species of Myrtaceae, with moderate purifying selection acting on this gene. The average nucleotide identity (ANI) analysis of the whole plastomes produced phylogenetic trees supporting the monophyly of three Myrtaceae tribes. The findings of this study provide support for planning conservation, breeding, and biotechnological programs for this species.

ABSTRACT Erythrina crista-galli is a native tree from South America with an important role on pharmaceutical studies. The objective of this study was to model the ancient and current ecological niches distribution of E. crista-galli in South America, contributing to the discussion about species management and conservation. A reduction in the potential area of species occurrence was detected by comparing past and present distribution. Based on the obtained results, it is expected that this species tends to expand its frontiers if the natural dynamic of the extant populations is guaranteed in southern South America. Therefore, management and conservation of E. crista-galli should focus on allowing the expansion of native forest formations where this species occurs. Additionally, further studies on the medicinal properties of the species may valorize and promote a higher interest in rational exploitation and conservation of E. crista-galli in its natural environment.

Abstract: Eugenia uniflora L. (Myrtaceae) is a tree species widely distributed in South America suffering the effects of the exploitation of natural populations. In this study, we employed low coverage sequencing of the E. uniflora genome for mining of SSR markers. The de novo assembly generated 2,601 contigs with an average length of 1139 bp and spans 3.15 Mb. A total of 76 dimer, 33 trimer and two compound SSR loci were identified. Twelve selected SSR loci were employed to genotype 30 individuals from two natural populations. A total of 73 alleles were detected (mean A= 6.1) were observed, the mean effective number of alleles was Ae = 3.91, mean Ho was 0.23 and mean HE was 0.70). The mean Wright’s within population fixation index was FIS = 0.66 and significant deviation of HWE was observed in all loci, except one. The FST between populations equaled 0.27. The levels of genetic diversity and structure estimated with these 12 SSR markers are in accordance with data from genetics studies performed on other tree species of the Pampa biome, presenting moderate to high polymorphism and may be employed in studies of species conservation measures and breeding programs.

RESUMO: Neste trabalho, objetivou-se avaliar a eficiência dos métodos de superação de dormência de sementes, em diferentes períodos de armazenamento, na produção de mudas de nogueira-pecã. As sementes foram submetidas aos seguintes tratamentos: T1, T4 e T7 - testemunhas (sementes sem qualquer método de tratamento, armazenadas em ambiente não controlado por 30, 60 e 90 dias, respectivamente), T2, T5 e T8 - estratificação (sementes distribuídas em caixas com areia úmida e mantidas em temperatura de 4°C por 30, 60 e 90 dias, respectivamente), T3, T6 e T9 - escarificação + estratificação (sementes escarificadas com lixa n.80 e estratificadas também por 30, 60 e 90 dias, respectivamente), em delineamento experimental inteiramente ao acaso. Avaliou-se, após 14 semanas da semeadura, altura das plantas, diâmetro do colo, número de folhas, emergência total e índice de velocidade de emergência (IVE). O melhor desenvolvimento das plantas de nogueira-pecã, bem como sua emergência e IVE foi observado no tratamento com estratificação por 90 dias e quando combinado escarificação e estratificação por 90 dias. O armazenamento das sementes em ambiente não controlado reduz sua viabilidade.

ABSTRACT: This study evaluated the efficiency of methods to overcome seed dormancy in different storage periods in the production of pecan seedlings. Seeds were submitted to the following treatments: T1, T4 and T7 - control treatments (seeds with no treatment, stored at room temperature for 30, 60 and 90 days, respectively), T2, T5 and T8 - stratification (seeds were distributed in boxes with wet sand maintained at a temperature of 4°C for 30, 60 and 90 days, respectively), T3, T6 and T9 - scarification + stratification (seeds scarified with sandpaper n.80 and stratified by 30, 60 and 90 days, respectively), in completely random experimental design. Plant height, stem diameter, number of leaves, full emergence and emergence speed index (ESI) were evaluated after 14 weeks of sowing. The best development of pecan 'plants, their emergence, and ESI were observed in the stratification treatment for 90 day as well as in the scarification + stratification treatment for 90 day. Storing seeds in uncontrolled environment reduced their viability.

Despite the importance of medicinal plants for the healthcare of local people, the knowledge about medicinal species used in the Pampa biome has been neglected over the years. In this study, an ethnobotanical survey was employed aiming to characterize the species richness and diversity of commercialized medicinal plant species in five cities within the Brazilian Pampa. Additionally, among the listed plants, ten species were selected for in vitro testing of their potential antioxidant activity. A total of 56 plant species belonging to 33 botanical families were listed by the 115 interviewees. No significant difference in commercialized medicinal plant species, and very similar species richness was observed among the cities, indicating that the local knowledge is consistently preserved across the studied cities. According to the biochemical analysis, Sphagneticola trilobata, Malva parviflora and Struthanthus flexicaulis emerged as very promising species for antioxidant activity. Further studies are recommended to advance our knowledge about the richness of medicinal plant species in the Brazilian Pampa, and to assess their therapeutic potential.

Resumo: O objetivo deste trabalho foi avaliar o efeito da estratificação de sementes na taxa de germinação, na velocidade de germinação e no desenvolvimento inicial de mudas de seis cultivares de nogueira-pecã (Carya illinoinensis) sob condições climáticas subtropicais, no Sul do Brasil. Para estratificação, as sementes foram acomodadas em caixas com areia úmida, em câmara fria a 4°C, por 90 dias. Na décima quarta semana após o plantio, foram avaliados o índice de velocidade de emergência, a emergência total, a altura da planta, o diâmetro do caule e o número de folhas. A estratificação das sementes melhora significativamente o potencial de germinação e as características morfológicas das cultivares avaliadas.

Abstract: The objective of this work was to evaluate the effect of seed stratification on germination rate, germination speed, and initial development of seedlings of six pecan (Carya illinoinensis) cultivars under subtropical climatic conditions in southern Brazil. For stratification, the seeds were placed in boxes with moist sand, in a cold chamber at 4°C, for 90 days. In the fourteenth week after sowing, the emergence speed index, total emergence, plant height, stem diameter, and number of leaves were evaluated. Seed stratification significantly improves the germination potential and morphological traits of the evaluated cultivars.

ABSTRACTStudies on phenotypic variation among populations growing in different microenvironments may provide information about plasticity related to environmental pressures, and thus help to elucidate the potential evolutionary forces contributing to the origin and maintenance of diversity in any region. In this study we investigate morphometric variation on a small geographic scale for three species of Antarctic mosses. All species revealed significant differentiation among populations for all evaluated traits. The comparison of morphometric measures of populations of Polytrichum juniperinumfrom Nelson Island and from southern Brazil suggests that the effects of a small geographic scale in Antarctica are the same as a large geographic scale in environments where the climate is more homogeneous and microhabitats have minor influence on vegetation. However, further investigations over a larger area, evaluating more species, and using controlled garden experiments are recommended in order to evaluate the capacity for plasticity of moss species in different climatic conditions and on different geographic scales.