Georgia Pacheco

A diversidade da flora endêmica e ameaçada do estado do Rio de Janeiro destaca-se por reunir 513 espécies, incluindo Pleroma hirsutissimum, recentemente redescoberta em Cabo Frio, e que estava classificada como criticamente em perigo (CR). Essa espécie, anteriormente conhecida como Tibouchina hirsutissima, foi realocada após uma revisão taxonômica. Partindo da última coleta documentada em 1982, realizamos esforços de busca direcionada na Região dos Lagos, os quais resultaram na identificação de novas populações. A região de Cabo Frio, reconhecida como enclave fitogeográfico, é vital para a conservação da biodiversidade, mas enfrenta ameaças devido à expansão urbana. O redescobrimento de P. hirsutissimum, em 2020, na Praia do Peró, desencadeou ações de conservação, incluindo a identificação de novas populações em áreas de dunas e pós-praia próximas de áreas alagadiças e a inserção de registros atualizados nos herbários do estado. Algumas ações de conservação foram desenvolvidas; entretanto, ainda há necessidade urgente de medidas de conservação das espécies nas restingas do Rio de Janeiro, evidenciada pela pressão da especulação imobiliária e de espécies exóticas invasoras.

Cactaceae is a predominantly Neotropical plant family comprising approximately 1,450 species, of which 31% are currently threatened. In Brazil, 301 species across 35 genera are recorded, with 108 species documented in the state of Minas Gerais. This study aimed to produce a monographic treatment of the Cactaceae occurring in Itacolomi State Park (ISP), a protected conservation unit within the Atlantic Forest phytogeographic domain, located in the Iron Quadrangle region of southeastern Brazil. A preliminary floristic survey of the park had recorded only two species of the family; however, herbarium data (BHCB, OUPR, RB, VIC) and recent field collections pointed to the need for an updated and comprehensive inventory. A total of six genera and 11 species were identified: Rhipsalis (four spp.), Lepismium (two spp.), Pereskia (two spp.), and one species each of Brasiliopuntia, Epiphyllum, and Hatiora. Rhipsalis floccosa subsp. pulvinigera (epiphytic), and Hatiora salicornioides (rupicolous) were widely distributed across Campos Rupestres and seasonal forests, whereas Brasiliopuntia brasiliensis showed a more restricted distribution. Most species have small, localized populations; however, Rhipsalis crispata is currently considered threatened with extinction. This study provides an identification key, morphological descriptions, photographs, ecological data, and conservation assessments, contributing to the knowledge of the family within Itacolomi State Park.

Brazil is a megadiverse country with continental dimensions. It is long acknowledged as the richest country in plant diversity, encompassing approximately 20% of the world’s flora, with more than 50,000 species of plants, algae and fungi distributed in six major biomes, including two biodiversity hotspots. However, significant environmental challenges, primarily driven by climate changes and intensive, non-sustainable land use practices, have led to widespread deforestation, habitat reduction and, consequently, shifts in species distribution, genetic erosion and increased vulnerability. Considering the high rates of endemism and the global economic value of numerous Brazilian native species as crops and wild relatives, ornamentals and medicinal plants, cryopreservation emerges as a fundamental ex situ complementary strategy to safeguard its plant genetic resources. This article aims to provide a comprehensive overview of cryopreservation of native plants in Brazil during the past decade, which shows that more than 85 species from 23 families have been cryopreserved. Methods for assessing cryoinjury at the morphophysiological, biochemical, molecular and metabolic levels are reviewed. The main challenges, as well as future perspectives for the cryopreservation of Brazilian floristic diversity, are also discussed.

Passiflora L., the largest genus of Neotropical lianas, belongs to the family Passifloraceae and encompasses 615 accepted species as concluded in the present research. Historically, various taxonomic classifications have been proposed for the genus. One such proposal divided the genus into 23 subgenera. Subsequent revisions reduced this number to four and later expanded it to the six currently recognized subgenera. Recent phylogenetic analyses using molecular markers have confirmed the monophyly of these subgenera. However, no study has used pollen characteristics for the taxonomic delimitation of subgenera of Passiflora. Given the importance of pollen morphology in taxonomy, this study aims to present taxonomic and palynological descriptions, illustrations, an identification key, and a list of species of the subgenera Astrophea, Deidamioides, Decaloba, Passiflora, Tetrapathea, and Tryphostemmatoides.

Passiflora suberosa, commonly known as corky passionflower or corky stem passion fruit, is a wild passion fruit species with agronomic, ornamental, and medicinal potentials. In a previous study, we developed an efficient protocol for long-term conservation of P. suberosa through the cryopreservation of shoot tips, using the V-Cryo-plate technique, and identified osmoprotection and cryoprotectant exposure as the critical stages influencing post-freezing recovery. The present work aimed to evaluate the effect of antioxidants on recovery rates and the metabolic stability of plants derived from cryopreserved shoot tips. The addition of different concentrations of ascorbic acid or glutathione during the osmoprotection and cryoprotection stages did not improve the recovery rates. High-Performance Liquid Chromatography (HPLC) analysis of in vitro plants derived from cryopreserved materials indicated that the biosynthetic capacity of the recovered plants was unaffected by the cryopreservation process. Furthermore, no significant changes were observed in the antioxidant potential of the recovered plants, as assessed by their ability to scavenge DPPH radicals and chelate metal ions. These results confirm that cryopreservation is an effective long-term conservation strategy for P. suberosa and provide new insights into the cellular responses of tropical plants to the stress induced by the procedures involved in V-Cryo-plate protocols.

Passiflora species are well known for their common use in popular medicine for the treatment of several diseases, such as insomnia, anxiety, and hysteria, in addition to their anti-inflammatory, antioxidant, analgesic and antibacterial potential. However, few data about the chemical composition and the medicinal potential of in vitro derived materials are available. Therefore, the goal of this work was to compare, for the first time, the phytoconstituents of in vitro derived materials of four Passiflora species, and evaluate the antibacterial potential of their extracts against 20 Gram-positive and negative strains. Chromatographic analysis indicated the presence of saponins in roots extracts from all studied species, whereas leaf extracts presented both saponins and flavonoids. Extracts from leaves and roots of P. alata and P. foetida exhibited a selective inhibitory activity against B. thuringiensis and S. pyogenes, which might be related to the presence of a high concentration of secondary metabolites, including flavonoids and saponins.