Low genetic diversity and significant structuring in the endangered Mentha cervina populations and its implications for conservation

Eighteen populations of the endangered aromatic and medicinal plant Mentha cervina (Lamiaceae) were sampled across its natural range, in the western half of the Iberian Peninsula, and inter-simple sequence repeats (ISSRs) markers were used to assess genetic diversity and population structure. M. cervina populations exhibited a relatively low genetic diversity (percentage of polymorphic loci PPB ¼ 14.2–58.3%, Nei’s genetic diversity He ¼ 0.135–0.205, Shannon’s information index I ¼ 0.08 0.33). However, the genetic diversity at species level was relatively high (PPB ¼ 98.3%; He ¼ 0.325; I ¼ 0.23). The results of the analysis of molecular variance indicated very structured populations, with 50% of the variance within populations, 44% among populations and 6% between regions defined by hydrographic basins, in line with the gene differentiation coefficient (GST ¼ 0.532). A Mantel test did not find significant correlation between genetic and geographic distance matrices (r ¼ 0.064), indicating that isolation by distance is not shaping the present genetic structure. The levels and patterns of genetic diversity in M. cervina populations were assumed to result largely from a combination of evolutionary history and its unique biological traits, such as breeding system, low capacity of dispersion, small effective size and habitat fragmentation. The high genetic differentiation among populations indicates the necessity of conserving the maximum possible number of populations. The results also provide information to select sites for ex situ conservation. Optimal harvesting strategies, cultivation and tissue culture should also be developed as soon as possible to guarantee sustainable use of the species under study

Flora da Bahia: Catasetum (Orchidaceae)

The floristic survey of Catasetum (Orchidaceae) from the state of Bahia, Brazil, is presented. Six species were recognized: C. blackii, C. hookeri, C. luridum, C. macrocarpum, C. purum, and C. roseo-album. The treatment includes description of taxa, as well as key for identification, illustrations, and commentaries for species.É apresentado o levantamento florístico de Catasetum (Orchidaceae) do estado da Bahia, Brasil. Foram reconhecidas seis espécies: C. blackii, C. hookeri, C. luridum, C. macrocarpum, C. purum e C. roseo-album. O tratamento inclui descrições dos táxons, além de chave de identificação, ilustrações e comentários para as espécies

Linear and geometric morphometrics as tools to resolve species circumscription in the Pseudolaelia vellozicola complex (Orchidaceae, Laeliinae)

Background and aims – Pseudolaelia is a genus endemic to eastern Brazil, with 12 accepted species predominantly distributed across granitic inselbergs of the Brazilian Atlantic Forest. The aim of the present study was to distinguish between the very similar taxa P. aguadocensis, P. oliveirana, P. regentii and P. vellozicola, using morphometric data acquired as linear measurements and outlines capture with Elliptic Fourier Analysis (EFA) of the floral parts. Material and methods – We sampled 208 specimens from 11 natural populations of the above taxa. We measured 20 floral variables and for the EFA, and we extracted 24 shape variables from the Fourier coefficient matrices, which describe the outlines of the floral parts. In both cases the data were analyzed with multivariate methods (both ordination and clustering). Key results – We could not find morphological discontinuities with sufficient magnitude to consider P. aguadocensis, P. oliveirana and P. regentii as distinct species from P. vellozicola. Conclusions – We propose that P. vellozicola should be considered a polymorphic and widely distributed species, generally supported by both methods

O gênero Capanemia Barb. Rodr. (Oncidiinae: Orchidaceae) na Região Sul do Brasil

Capanemia includes seven predominantly Brazilian epiphyte orchids, distributed by Uruguay, Paraguay, Northeastern Argentina, part of Bolivia and mainly areas of the South and Southeastern regions of Brazil, in humid forest between 450 to 1.400 m of altitude. A few species reach Uruguay, Paraguay, Northeastern Argentina and part of Bolivia. This work is focused in the species that occur in Southern Brazil and presents relevant synonymies, an artificial key for the identification of the species, descriptions, illustrations, geographic distribution, new record, habitat and additional comments for all the Southern Brazilian species.O gênero Capanemia abrange sete espécies de orquídeas epífitas distribuídas do Uruguai, Paraguai, extremo Nordeste da Argentina, parte da Bolívia e principalmente em florestas das regiões Sul e Sudeste do Brasil, entre 450 e 1.400 m de altitude. Este trabalho se restringe a revisar as espécies ocorrentes na região Sul do Brasil e apresentar sinonímias relevantes, uma chave analítica para a identificação das espécies, descrições, ilustrações, distribuição geográfica, novas citações, habitat e comentários adicionais para todas as espécies da região

Genetic diversity in Mentha cervina based on morphological traits, essential oils profile and ISSRs markers

Morphological, phytochemical and genetic differences were studied to evaluate the level and distribution of diversity in twelve populations of the Portuguese endangered medicinal plant Mentha cervina L. Morphological variation was correlated with ecological conditions at the site of origin. Pulegone was the major essential oils compound in all of the populations collected at full flowering (68–83%), in different growing conditions (51–82%), and for all the developmental stages studied (47–82%). Although clusters were defined, the analysis revealed a high chemical correlation among all populations (Scorr 0.95%). Intersimple sequence repeats markers were used to assess the population structure and genetic variation. Populations exhibited a relatively low genetic diversity (PPB ¼ 14.3–64.6%, He ¼ 0.051–0.222, I ¼ 0.076–0.332), with high structuring between them (GST ¼ 0.51). However, the genetic diversity at species level was relatively high (PPB ¼ 97.7%; He ¼ 0.320). The levels and patterns of genetic diversity were assumed to result largely from a combination of evolutionary history and its unique biological traits, such as breeding system, clonal growth, low capacity of dispersion and habitat fragmentation. The relatively low genetic diversity in the populations analyzed indicates that the maintenance of their evolutionary potential is at risk if population sizes are maintained and if there is no protection of the habitats

Flora da Bahia: Encyclia (Orchidaceae)

A survey of Encyclia (Orchidaceae) species in Bahia state, Brazil, is performed as a contribution to the flora of this region. We recognized 13 species, and one variety of Encyclia from Bahia. A key for identification, descriptions, illustrations and commentaries for taxa are presented. We propose the synonymization of E. silvana under E. bohnkiana and the lectotypification of Epidendrum roseum and its synonymization under Encyclia dichroma.É apresentado o levantamento das espécies de Encyclia (Orchidaceae) ocorrentes no estado da Bahia, Brasil, como contribuição à flora do Estado. São reconhecidas 13 espécies e uma variedade de Encyclia na Bahia. É apresentada uma chave de identificação, além de descrições, ilustrações e comentários gerais para os táxons. É proposta a sinonimização de E. silvana sob E. bohnkiana e a lectotipificação de Epidendrum roseum e sua sinonimização sob Encyclia dichroma

A tecnologia CRISPR/Cas9 aplicada ao modelo biológico Drosophila melanogaster / CRISPR/Cas9 technology applied to the Drosophila melanogaster biological model

O CRISPR/Cas9 é um mecanismo de memória adaptativa bacteriano que se apresenta como uma das plataformas mais eficazes de edição genética, permitindo manipular de forma precisa qualquer sequência genômica. Ao longo de uma década foram feitas inúmeras publicações utilizando esta técnica em diversos modelos biológicos, com diferentes finalidades. A Drosophila melanogaster é um modelo biológico utilizado massivamente nos trabalhos na área da Genética e também tem sido alvo de interesse nos experimentos realizados com CRISPR/Cas9, justamente pelas características inerentes ao sucesso desse modelo biológico que conta com ciclo de vida curto, fenótipos facilmente observáveis, genoma pequeno e numerosos descendentes ao longo das gerações, o que permite avaliar facilmente os resultados de edição genômica promovido pela técnica. É apresentada uma revisão sistemática das publicações em inglês e português, no recorte temporal de 2010 a 2020, nas plataformas on-line: Science Direct e Microsoft Academic Search, buscando analisar as metodologias, genes alvo e singularidades dos protocolos apresentados afim de descrever um protocolo inicial de execução da técnica CRISPR-Cas9 em D. melanogaster. Foram encontrados 4181 artigos e filtrados 48 a partir de critérios estabelecidos para inclusão e exclusão. Os principais resultados encontrados conferem aos genes mais utilizados, fase de aplicação de microinjeção nas drosófilas, montagem do plasmídeo para edição gênica e pH específico para a solução da injeção. Conclui-se que a técnica ainda precisa ser aprimorada em estudos que visam múltiplos genes, sendo necessário reduzir a perspectiva de cortes fora do alvo genético de interesse e simplificação da construção do vetor de edição. No entanto, a montagem da técnica associada a simplicidade de manuseio em Drosophila mostra-se de coerente aplicabilidade em centros de pesquisa nacionais desde que as instituições atentem ao rigor ético necessário à tal manipulação

Filogenia molecular, morfologia e suas implicações para a taxonomia de Eriocaulaceae

The pantropical family Eriocaulaceae includes ten genera and c. 1,400 species, with diversity concentrated in the New World. The last complete revision of the family was published more than 100 years ago, and until recently the generic and infrageneric relationships were poorly resolved. However, a multi-disciplinary approach over the last 30 years, using morphological and anatomical characters, has been supplemented with additional data from palynology, chemistry, embryology, population genetics, cytology and, more recently, molecular phylogenetic studies. This led to a reassessment of phylogenetic relationships within the family. In this paper we present new data for the ITS and trnL-F regions, analysed separately and in combination, using maximum parsimony and Bayesian inference. The data confirm previous results, and show that many characters traditionally used for differentiating and circumscribing the genera within the family are homoplasious. A new generic key with characters from various sources and reflecting the current taxonomic changes is presented