Ana Odete Santos Vieira

Karyotype differentiation of four Cestrum species (Solanaceae) based on the physical mapping of repetitive DNA

We studied the karyotypes of four Brazilian Cestrum species (C. amictum, C. intermedium, C. sendtnerianum and C. strigilatum) using conventional Feulgen staining, C-Giemsa and C-CMA3/DAPI banding, induction of cold-sensitive regions (CSRs) and fluorescent in situ hybridization (FISH) with rDNA probes. We found that the karyotypes of all four species was 2n = 2x = 16, with, except for the eighth acrocentric pair, a predominance of meta- and submetacentric chromosomes and various heterochromatin classes. Heterochromatic types previously unreported in Cestrum as neutral C-CMA30/DAPI0 bands, CMA3+ bands not associated with NORs, and C-Giemsa/CSR/DAPI- bands were found. The heterochromatic blocks varied in size, number, position and composition. The 45S rDNA probe preferentially located in the terminal and subterminal regions of some chromosomes, while 5S rDNA appeared close to the centromere of the long arm of pair 8. These results suggest that karyotype differentiation can occur mainly due to changes in repetitive DNA, with little modification in the general composition of the conventionally stained karyotype.

Vascular flora of the Mata dos Godoy State Park, Londrina, Paraná, Brazil

The Mata dos Godoy State Park (MGSP) is a remnant of the Seasonal Semideciduous Forest in northern Parana, with an area of 690 hectares. The MGSP flora inventory was produced from a survey of herbarium specimens deposited in the FUEL Herbarium. The result was the catalogue of 508 species, among which we screened 40 specimens of ferns and lycophytes, and the remainder was classified as angiosperms. The two richest families among the ferns were Polypodiaceae and Pteridaceae, whereas among the arboreal angiosperms, Leguminosae and Myrtaceae stood out, confirming the floristic profile of the lower Tibagi River basin. Among the species, 12 can be classified as naturalized and 21 are among the threatened species in the state of Parana, besides the inclusion of species whose collections were reduced in Brazil. These results indicate the MGSP as an important area for the representation of the Seasonal Semideciduous Forest in northern Parana.

Espécies arbóreo-arbustivas da família Rubiaceae Juss. na bacia do rio Tibagi, PR, Brasil

Tree and shrub flora of the family Rubiaceae Juss. in the Tibagy river basin, Parana State, Brazil. Rubiaceae, the fourth largest family of angiosperms in number of species in the world, is renowned by the opposite leaves, interpetiolar stipules, gamopetalous corolla and inferior ovary. Although well represented in the herbaria collections, it has not yet been fully studied in Parana State. The Tibagy river basin is located in the center-eastern region of the Parana State and is divided into Upper, Middle and Lower Tibagy, covering 13% of the States total surface. A number of exsiccates from both the Parana herbaria collections and the field samplings conducted in the municipalities of the basin were collected, 1053 of which were analyzed. In this study, 18 genera and 35 species were recorded. Among those, Psychotria is the genus with greater species richness. The species Psychotria subtriflora, Psychotria tenuifolia, and Simira corumbensis were identified as new occurrence records for Parana State and Psychotria fractistipula as a new citation for the State. This survey broadens the taxonomic knowledge of the Rubiaceae family and its role in the flora of the Tibagy basin and in the State of Parana.

ESTRUTURA E RELAÇÕES FLORÍSTICAS DE UM FRAGMENTO DE FLORESTA ESTACIONAL SEMIDECIDUAL, LONDRINA, PARANÁ, BRASIL

The largest fragment of Figueira Farm (Londrina-PR state) with an area of 266 ha, is a Private Natural Heritage Reserve, and one of the most important remnants of the region. The aim of this study was to characterize the structure and tree diversity of this fragment, and evaluate the floristic relationship with other fragments of semideciduous forest studied in the state of Parana. One hundred plots of 10 x 10 m were allocated and the arboreal individuals with 15 cm or more in circumference at breast height were sampled, resulting in 1,569 individuals, 32 families, 66 genera and 93 species. Families with greater number of species were Fabaceae (16 species), Meliaceae (nine species) and Myrtaceae (nine species). Trichilia clausseni C.DC. was the species with the highest importance in the study, reflecting higher values of density and relative frequency in the fragment. The largest relative dominance was presented by Gallesia integrifolia (Spreng.) Harms, by presenting large individuals with the highest values of basal area. The Shannon diversity index was found to be 3.37 nats/ind, a value considered significant and similar to other surveys in the region, and the index of evenness by Pielou was 0.743, indicating balance in the number of individuals among species. The presence of singletons and rare tree species in Parana as well as the total diversity of species and the degree of conservation of the fragment, demonstrate the importance of the preservation and management of the remnant. Geographical proximity associated with similar environment factors as well as the predominant type of phytogeographic unit, showed closer floristic relationships, on the other hand, local environmental factors such as proximity to watercourses differentiated its flora of nearby places.