RESUMO
A National Forest Inventory (NFI) encompassing the entire territory of Brazil is in progress. It is coordinated and promoted by the Brazilian Forest Service of the Ministry of Environment. In each state, the NFI collaborates with local herbaria by receiving collected plant material and performing species identification. Consultants are hired by the NFI and work at the local herbaria under the supervision of a curator. In exchange for curatorial assistance, the NFI provides equipment and consumables for the herbarium. Other public projects collaborating with NFI are Reflora and the Brazilian Biodiversity Information System (SiBBr). Both projects have online platforms that seek to connect herbaria and make all their data freely available, including high quality digital images of specimens. Through inter-institutional collaboration, the joint interests of NFI, Reflora, SiBBr and local herbaria have improved collections, expanded the online Reflora database, and provided the NFI with verified species lists. These strategic uses of public funding are positively affecting Botany, particularly during a period of economic crisis and cuts in research. Here, we illustrate the increase in floristic knowledge through the improvement of a herbarium collection in Rio Grande do Norte (RN) - the Brazilian state with the lowest levels of plant richness. We report 71 new occurrences of vascular plants for RN, belonging mainly to the Poaceae, Fabaceae and Malvaceae. Most of the species with new occurrences have a Neotropical distribution (21 spp.) and only seven are restricted to the Brazilian Northeast. Our findings highlight previous gaps in RN's floristic knowledge. The partnership NFI, Reflora, SiBBr and the UFRN herbarium improved herbarium curation, digital collection, and quality of data. Finally, a fellowship provided by Reflora and SiBBr allowed improving curation by distributing duplicates and incorporating the Herbarium of Câmara Cascudo Museum.
RESUMO
Euphorbia Linnaeus, 1753 (Euphorbiaceae) is one of the most diverse and complex genera among the angiosperms, showing a huge diversity in morphologic traits and ecologic patterns. In order to improve the knowledge of the karyotype organization of Euphorbia hirta (2n = 18) and Euphorbia hyssopifolia (2n = 12), cytogenetic studies were performed by means of conventional staining with Giemsa, genome size estimations with flow cytometry, heterochromatin differentiation with chromomycin A3 (CMA) and 4',6-diamidino-2-phenylindole (DAPI) and Giemsa C-banding, fluorescent in situ hybridization (FISH) with 45S and 5S rDNA probes, and impregnation with silver nitrate (AgNO3). Our results revealed small metacentric chromosomes, CMA+/DAPI0 heterochromatin in the pericentromeric regions of all chromosomes and CMA+/DAPI- in the distal part of chromosome arms carriers of nucleolar organizing regions (NORs). The DNA content measurements revealed small genomes for both species: Euphorbia hirta with 2C = 0.77 pg and Euphorbia hyssopifolia with 2C = 1.41 pg. After FISH procedures, Euphorbia hirta, and Euphorbia hyssopifolia presented three and four pairs of terminal 45S rDNA sites, respectively, colocalizing with CMA+ heterochromatic blocks, besides only one interstitial pair of 5S rDNA signals. Additionally, the maximum number of active NORs agreed with the total number of observed 45S rDNA sites. This work represents the first analysis using FISH in the subfamily Euphorbioideae, revealing a significant number of chromosomal markers, which may be very helpful to understand evolutionary patterns among Euphorbia species.