ABSTRACT South Brazilian grasslands are among the most species-rich grasslands worldwide yet they have been suffering ongoing degradation due to land-use. Little is known about the reproductive ecology of the native species of these grasslands. Thus, our goal was to characterize seed traits and germination requirements of three native species of the tribe Tigridieae (Iridaceae, Iridoideae) due to its richness in the Pampa biome and the contrasting morphology, cytogenetics, and geographic distributions of its representatives. We tested if closely related species possess similar seed traits and whether species with wider distributions have broader germination requirements. Seed production and mass were estimated, and morphological analyses, germination experiments and viability tests were performed. Principal component analysis (PCA) was used to describe correlations between seed traits and species’ distributions. Germination was assessed using time-to-event analysis and the Cox model. All seed traits differed among the analyzed species/cytotypes. Final germination percentage (FGP) averaged 39.1 % and with overall viability of 89.9 %. Germination tests showed that seeds benefit from negative photoblasty. Species/cytotypes with wider distributions and heavier and larger seeds generally had better germination performances than narrower distributed species/cytotypes with lighter and smaller seeds.
Abstract Evolutionary analyses have been widely used for evaluation of genetic diversity of natural populations and correlate these data to the fitness of the species, especially in the case of threatened species. Calydorea crocoides occurs in a restricted area at altitudes from 800 to 1500 m in southern Brazil and is considered endangered. A study assessing genetic diversity, cytogenetic features and ecological niche was performed aiming to characterize C. crocoides by multidisciplinary approaches. Molecular data highlighted that most of the total variation (76%; p < 0.001) was found within populations and the parameters of genetic diversity were high at the species level (PPB = 98.97%; I = 0.4319; h = 0.2821). Gene flow (Nm) was estimated in 0.97 individuals per generation. Cytogenetically, C. crocoides presents a bimodal karyotype and low asymmetry. DAPI banding pattern was uniform, but the CMA-signal evidenced a pericentric inversion in the population ESC688. The species presents high pollen viability and two different morphologies of pollen grains. Our data showed high levels of polymorphism maintained in this species that could ensure conservationist practices in which the main goal is to preserve the evolutionary potential of the species through the maintenance of genetic diversity.
In Southern Brazil, the Polygalaceae family is represented by five genera: Acanthocladus, Bredemeyera, Monnina, Polygala, and Securidaca. The genus Polygala is the largest of the Polygalaceae family, with approximately 725 species widely distributed in the world, in all types of environment. Approximately 140 taxa of Polygala are known in the Brazilian flora. The survey recorded 39 species of Polygala to Southern Brazil, representing the subgenera Hebeclada, Ligustrina and Polygala, the last one with 31 species. Full descriptions, illustrations, analytical keys, data on habitat, geographic distribution, and ecological observations are provided.
A família Polygalaceae está representada por cinco gêneros no Sul do Brasil: Acanthocladus, Bredemeyera, Monnina, Polygala e Securidaca. O gênero Polygala é o mais abundante da família Polygalaceae, com aproximadamente 725 espécies mundialmente distribuídas nos mais diversos ambientes. Na flora brasileira são conhecidos 140 táxons de Polygala. Foram reconhecidas 39 espécies de Polygala para a região Sul do Brasil, pertencentes aos subgêneros Hebeclada, Ligustrina e Polygala, sendo o último o que concentra o maior número de espécies, 31. São fornecidas descrições dos táxons, ilustrações, chaves de identificação, dados sobre hábitat, distribuição geográfica e observações ecológicas.
Here we present a taxonomic study of the genus Monnina in Southern Brazil, based on a literature survey and herbaria revision, field work in Paraná, Santa Catarina and Rio Grande do Sul states, and observation of specimens in their native habitats. Nine species were recognized for Southern Brazil: Monnina cardiocarpa A. St.-Hil. & Moq., M. cuneata A. St.-Hil. & Moq., M. dictyocarpa Griseb., M. itapoanensis Vianna & Marques, M. oblongifolia Arechav., M.Â resedoides A. St.-Hil. & Moq., M. richardiana A. St.-Hil. & Moq., M. stenophylla A. St.-Hil. & Moq. and M. tristaniana A. St.-Hil. & Moq. Descriptions, illustrations, analytical keys, data on habitat, geographic distribution, ecological observations and additional comments are presented.
O trabalho trata do estudo taxonômico do gênero Monnina na Região Sul do Brasil. A metodologia apresentou uma revisão bibliográfica e de herbários nacionais e internacionais, coletas nos Estados do Paraná, Santa Catarina e Rio Grande do Sul, bem como observações das espécies em seus diferentes ambientes de ocorrência. Foram reconhecidas nove espécies para a Região Sul do Brasil: Monnina cardiocarpa A. St.-Hil. & Moq., M. cuneata A. St.-Hil. & Moq., M. dictyocarpa Griseb., M. itapoanensis Vianna & Marques, M. oblongifolia Arechav., M. resedoides A. St.-Hil. & Moq., M. richardiana A. St.-Hil. & Moq., M. stenophylla A. St.-Hil. & Moq. e M. tristaniana A. St.-Hil. & Moq. Neste trabalho são fornecidas descrições dos táxons, ilustrações, chaves analíticas, hábitat, distribuição geográfica, observações ecológicas e comentários adicionais.