The objective of this search was to quantify the genetic variability in progenies from grápia mother trees in natural populations, for initial growth characters of the seedlings. Seeds were collected from 13 mother trees, from four origins, located in the municipalities of Pareci Novo, São José do Sul and Aratiba in RS, and Seara in SC, as well as data from plants and place of origin. Biometrics were performed on 100 seeds lot from each mother tree, and an experiment was installed to evaluate progenies in a completely randomized design. It was evaluated the seedling emergence speed and the emergence percentage, the stem diameter and seedlings height, as well as the final survival percentage. A significative difference was found for all variables observed for seeds and seedlings of grápia mother trees. Seed length and width demonstrated high values for individual heritability in the narrow sense (above 0.6), being possible to use the seed size for an analysis of genetic variability between plants of the species, but not as an indicative variable of physiological quality and vigor. The correlation analysis indicated that the seedling emergence percentage is related to the characteristics of the mother plant plant (height and diameter). Thus, the use of seedlings for forest restoration areas is appropriate, as they have indications of genetic diversity.

Ecological succession is one of the most important processes in forest ecosystems, still poorly understood in the highland Araucaria forests of Southern Brazil. Here we investigated this process by describing functional composition changes in response to a vegetation successional mosaic in four forest fragments in the municipality of Urubici, State of Santa Catarina, Brazil. Two fragments were classified as in advanced stage of succession and two were classified in early stage. The following functional traits were determined: wood density, leaf area, specific leaf area, dispersal syndrome and leaf phenology. For each fragment, we determined the community weighted mean (CWM) and the functional diversity (RaoQ). Data were analyzed by descriptive statistics, t and Mann-Whitney tests and Principal Components Analysis. We found that the successional stage is a relevant source of functional heterogeneity. At the advanced-successional stage, tree communities have harder woods, more membranous and semi-deciduous leaves and higher functional diversity. Conversely, at the early successional stages, forests have softer wood, more coriaceous leaves and lower functional diversity. We concluded that the studied forests showed a high functional composition heterogeneity, partially determined by a successional mosaic. While perennial species with lower values of specific leaf area and wood density predominated in the early successional areas, semi-deciduous species with higher values of specific leaf area and wood density prevailed in the late successional ones.

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