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Context: Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known in Brazil as guabiroba, is a plant used as antidiarrheic, anti-inflammatory and antirheumatic agents, and in stomach and hepatic disorders. Objective: The antiproliferative and genotoxic effects of aqueous extracts and essential oil of C. xanthocarpa were evaluated. Materials and methods: Cytotoxicity and genotoxicity of the aqueous extracts (6 and 30 mg/mL) and essential oil (0.25%, v/v) obtained from leaves of C. xanthocarpa were evaluated using the Allium cepa L. (Amaryllidaceae) assay. Mitotic index was calculated as the percentage of dividing cells of total cells observed; chromosome abnormalities were observed and counted during cell division. Additionally, the composition of the essential oil and the quantification of the main compounds of the extracts were determined by gas chromatography/mass spectrometry and high performance liquid chromatography coupled with diode array detector, respectively. Results and discussion: Aqueous extracts (6 and 30 mg/mL) led to a reduction of 67.7% and 34.1% of the mitotic index, respectively, whereas the treatment with essential oil caused a 48.2% reduction in the mitotic index, when compared with negative control. Chromosomal mutations were observed and included anaphase bridges, delay chromosome, break chromosome, as well as metaphase with disorganized chromosomal and binuclear cells. The main compounds of the essential oil were b-caryophyllene (8.87%), viridiflorol (6.40%), spathulenol (5.16%), d-cadinene (4.92%), linalool (4.46%) and a-cadinol (4.25%). Gallic acid (3.19%), chlorogenic acid (1.04%), quercetin (2.97%) and rutin (4.82%) were identified in an aqueous extract (30 mg/mL). Conclusion: Our results demonstrated that genotoxic and antiproliferative activities are present in C. xanthocarpa infusions using the in vivo onion root-tip cell test.

Three new species and one subspecies of Cypella are described for Rio Grande do Sul (RS), Brazil: Cypella altouruguaya from northern RS, C. amplimaculata widely distributed across the state and C. rivularis restricted to southern RS, in grassland streams of the Pampa biome. Cypella hauthalii subsp. minuticristata is found in a central area of Rio Grande do Sul. The different taxa are described, illustrated and compared with related species. The resulting taxonomic framework shows that most of the species described for Cypella occur in the Río de la Plata grasslands, with various infrageneric taxa characterised by a high level of endemism, especially in the Subtropical Grasslands of Southern Brazil.

The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora.

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ResumoA espécie Conyza bonariensis (L.) Cronquist, conhecida por buva, pertence à família Asteraceae e é originária da América do Sul. Apresenta ciclo de desenvolvimento anual e é prolífica, podendo produzir até 200.000 sementes por planta, estabelece-se em diversas condições climáticas, apresenta boa adaptabilidade, sendo, geralmente, considerada planta daninha, mas também usada como medicinal. Para auxiliar na identificação precisa dessa espécie, este trabalho teve como objetivo realizar a caracterização citogenética, partindo de sementes coletadas em populações ocorrentes na região do planalto médio do Rio Grande do Sul. Para determinação do número de cromossomos, as sementes foram colocadas para germinar em placas de Petri com papel filtro duplo no germinador a 20 o C. As radículas com 2 a 5 mm de comprimento foram coletadas e submetidas ao pré-tratamento a frio (4 o C) por 18h, fixação em etanol: ácido acético (3:1) por 24h a temperatura ambiente e conservação em álcool 70% sob refrigeração até o uso. Para o preparo das lâminas, as radículas foram hidrolisadas em HCl 2N por 5 min, lavadas em água destilada e coradas com orceína acética (2%) pela técnica de esmagamento. As lâminas foram analisadas em microscópio ótico com auxí-lio da objetiva de 40x e 100x. Os resultados obtidos para as populações oriundas [39][40][41][42][43][44][45][46][47][48] 2012 40 de diferentes locais do RS foram 2n=4x=36 cromossomos para as populações de Júlio de Castilhos, Tupanciretã, Cruz Alta, Victor Graeff; e 2n= 5x= 45 para a população de Não-Me-Toque, correspondendo morfologicamente a Conyza bonariensis var. microcephala (Cabrera) Cabrera, com exceção da população de Tupanciretã, a qual se trata de Conyza bonariensis var. bonariensis. Palavras-chave: Asteraceae, buva, número de cromossomos, planta daninha. AbstractThe species Conyza bonariensis, known as hairy fleabane, belongs to the Asteraceae family and has its origin in South America. It has an annual cycle of life, being prolific and able to produce up to 200,000 seeds per plant. It occurs in various climatic conditions, showing good adaptability, and is generally considered weed, but also used as medicinal. To help on the identification of this species, the study aimed to perform cytogenetic characterization, starting from seeds collected of populations occurring in the higmedium plains region of Rio Grande do Sul. To determinate the number of chromosomes, the seeds were germinated and the root-tips with 2-5 mm in length were collected and subjected to cold pretreatment (4°C) for 18h, fixed in ethanol: acetic acid (3:1) for 24h and kept in 70% ethanol under refrigeration. For the preparation of slides, the root-tips were hydrolyzed in 2N HCl for 5 min and stained with acetic orcein (2%) by the squashing technique. The results were 2n = 36 chromosomes to populations of Julio de Castilhos, Tupanciretã, Cruz Alta, Victor Graeff; and 2n = 5x = 45 for the population of Nao-Me-Toque, morphologically corresponding to Conyza bonariensis var. microcephala, except the populatio...

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RESUMO:A espécie Polygonum punctatum Elliott (Polygonaceae) é amplamente utilizada pela população como planta medicinal. O objetivo deste trabalho é o de avaliar o potencial genotóxico e mutagênico de P. punctatum utilizando raízes de bulbos e radículas em sementes germinadas de Allium cepa através do teste in vivo, e realizar comparações da extração do material vegetal por calor (infusões) e extração a frio (extrato). Para isso, foram preparadas dois tipos de soluções, infusões e extratos foliares de P. punctatum, em duas concentrações 0,4 g mL -1 e 2,4 g mL -1 . A infusão foi preparada pela adição das folhas secas em água destilada fervente (100ºC), permanecendo por 10 minutos enquanto o extrato foi preparado através da maceração das folhas secas em água destilada fria. Para o teste em A. cepa foram utilizados, para cada tratamento, seis grupos de quatro bulbos e seis caixas gerbox com 50 sementes em cada caixa. Duas lâminas para cada tratamento foram obtidas através da técnica de esmagamento das raízes e coradas com orceína acética 2%. Foram contadas 2000 células por grupo de bulbos e 3000 células por grupo de sementes, observando-se a ocorrência de interrupções em metáfases, alterações cromossômicas estruturais, bem como a inibição ou aumento da divisão celular. Os valores do índice mitótico foram calculados e analisados estatisticamente pelo Teste χ 2 (p≤0,05). Os resultados demonstraram que as infusões e os extratos de folhas apresentaram redução nos valores de índices mitóticos nas concentrações utilizadas em relação ao controle em água destilada. Foram identificadas alterações cromossômicas na divisão celular, tais como pontes anafásicas, em todas as concentrações de infusões e extratos indicando assim que P. punctatum possui atividade antiproliferativa e genotóxica. Palavras-chave:Polygonum punctatum, genotoxicidade, plantas medicinais, Allium cepa.ABSTRACT: Genotoxic and antiproliferative action of Polygonum punctatum Elliott (Polygonaceae) on the cell cycle of Allium cepa L. The species Polygonum punctatum Elliott (Polygonaceae) is widely used by the Brazilian population as a medicinal plant. The aims of this study are to evaluate the genotoxic and mutagenic potential of P. punctatum, using its root bulbs and rootlets in germinated seeds of Allium cepa by in vivo testing, and to compare the extraction of plant material by heat (infusions) and cold (extract). Thus, two types of solutions -infusions and leaf extracts -of P. punctatum were prepared at the two concentrations of 0.4 g ml -1 and 2.4 g mL -1 . The infusion was prepared by addition of dry leaves in boiling distilled water (100°C), remaining for 10 minutes, while the extract was prepared by maceration of dried leaves in cold distilled water. For the A. cepa, we used for each treatment six groups of six bulbs and six seedling boxes with 50 seeds each. Two slides for each treatment were obtained by the technique of crushing the roots, and they were stained with 2 % acetic orcein. For the analysis, 2000 cells per group of bulbs and 3000 cells per...