Genetic and demographic aspects of Varronia curassavica Jacq. in a heterogeneous coastal ecosystem.

The restinga is a threatened Brazilian ecosystem and a highly heterogeneous environment. This work aimed to evaluate demographic and genetic aspects of Varronia curassavica and whether environmental heterogeneity can influence the studied population parameters. Three annual evaluations were carried out in an area of restinga in Florianópolis-SC, Brazil. Demographic data were analyzed using descriptive statistics, and the spatial distribution pattern was calculated by Ripley's K-function and correlated with environmental characteristics. To characterize diversity and genetic structure, eight microsatellite markers were used. This work demonstrated that variations in the distribution of individuals and genotypes can be related to specific environments. Dry lowlands were environments favorable to population development, and flooded lowland and mobile dunes were unfavorable. The fixation indices were distinct between environments, evidencing a tendency toward preferential crosses in favor of heterozygotes. We found absence of spatial genetic structure, indicating that genotypes are randomly distributed and that gene flow may be related to such genetic factors as the presence of autoincompatibility mechanisms. This diversity of environments contributed to the aggregate distribution and is relevant for the maintenance of demographic and genetic processes of the species in restingas, and this aspect should be considered for in situ conservation.

Consumption of Euterpe edulis fruit by wildlife: implications for conservation and management of the Southern Brazilian Atlantic Forest.

This study aimed to measure the wildlife consumption of Euterpe edulis fruit and use this data to discuss management possibilities. To estimate infructescence fruit volume consumed, collectors were installed in fruit-bearing palms. To characterize consumption from the ground, samples were placed next to fruiting palms. To identify wildlife and their activities, camera traps were installed in infructescences and on the ground. The results suggested that there was a small fruit surplus (1.8 %), and this finding indicated the possibility of a harvest to reduce food for the wildlife. However, recurrent variations in the annual fruit production (21.4 %) were also noted, and suggested that wildlife could tolerate some fruit harvesting. Thus, a harvest could be restricted to fruit volume that exceeds the annual average (94 kg/ha/year). Turdus flavipes, a migratory bird, was the most active species in the dispersal of seeds; this finding indicates the need for broader conservation strategies. Wildlife composition also changed along with the fruiting, and this alteration suggests that dependence on the fruit is variable among different species. Seed germination and seedling mortality were high, results that indicate that local conditions may have a predominant effect on seed volume in natural regeneration density.

Reproductive Biology of Varronia curassavica Jacq. (Boraginaceae)

ABSTRACT Varronia curassavica, a subshrubby medicinal species associated with restinga in the Atlantic Forest, has been exploited by local people and the pharmaceutical industry. Indeed, restingas have experienced a continuous process of degradation, and thus, with species and ecosystem both at risk, efforts to support conservation actions are required. The present study aimed to evaluate aspects of V. curassavica reproductive biology. To accomplish this, morphological characterization was performed by monitoring flowering events. The availability of nectar and pollen, as well as the frequency and behavior of floral visitors and dispersers, was also evaluated. This species exhibits both heterostyly and protogyny. Anthesis is diurnal, and flowers last less than a day. The high number of flower and fruit abortions suggests that mechanisms, such as self-incompatibility intra-morphs and easily detached flowers, contribute to reduced fruit production. The high diversity of floral visitors indicate a generalist pollination syndrome. Diptera, Hymenoptera and Lepidoptera were the main pollinators, and nectar was the main resource sought by these insects. Fruits were dispersed by birds and ants. It can be concluded that the interaction of V. curassavica with several species is a key factor in its own survival and for maintaining the biological diversity of restinga.

Reproductive Biology of Varronia curassavica Jacq. (Boraginaceae).

Varronia curassavica, a subshrubby medicinal species associated with restinga in the Atlantic Forest, has been exploited by local people and the pharmaceutical industry. Indeed, restingas have experienced a continuous process of degradation, and thus, with species and ecosystem both at risk, efforts to support conservation actions are required. The present study aimed to evaluate aspects of V. curassavica reproductive biology. To accomplish this, morphological characterization was performed by monitoring flowering events. The availability of nectar and pollen, as well as the frequency and behavior of floral visitors and dispersers, was also evaluated. This species exhibits both heterostyly and protogyny. Anthesis is diurnal, and flowers last less than a day. The high number of flower and fruit abortions suggests that mechanisms, such as self-incompatibility intra-morphs and easily detached flowers, contribute to reduced fruit production. The high diversity of floral visitors indicate a generalist pollination syndrome. Diptera, Hymenoptera and Lepidoptera were the main pollinators, and nectar was the main resource sought by these insects. Fruits were dispersed by birds and ants. It can be concluded that the interaction of V. curassavica with several species is a key factor in its own survival and for maintaining the biological diversity of restinga.

Bark harvesting systems of Drimys brasiliensis Miers in the Brazilian Atlantic rainforest.

Drimys brasiliensis Miers, locally known as cataia or casca-de-anta, is a native tree species of the Atlantic Rainforest. Its bark is harvested from natural populations. This study examined the recovery capacity of the bark of D. brasiliensis under different bark harvesting methods, as well as the influence of these approaches on its population dynamics and reproductive biology. While none of these treatments resulted in changes in phenological behavior or the rate of increase of diameter at breast height and tree height, the removal of wider bark strips resulted in lower rates of bark recovery and higher rates of insect attack and diseases. Accordingly, the results recommend using strips of bark 2 cm wide and 2 m long, with 4 cm between strips, for effective rates of bark regrowth and for lower susceptibility to insect attack and diseases. From these studies, we concluded that D. brasiliensis has a high potential for sustainable management of its natural populations, demonstrating the possibility of generating an important supplementary income for farmers and contributing to the use and conservation of the Atlantic Rainforest.

Agriculture, biodiversity and appropriate biotechnologies in Brazil

The emergence of biotechnologies and new plant breeding programs occurs in a contex of the green revolution based system. These programs could be based on the rational use of biodiversity and directed to sustainable agriculture. In Third World countries the system shows signs of exhaustion. Brazil is the country with the world's largest genetic diversity of plants, comprising over 55,000 identified species of an estimated total ranging from 350,000 to 550,000. The use of such biodiversity brings about the discussion on the interests of northern hemisphere countris - rich in financial resources and technology yet poor in genetic resources - and Southern Hemisphere countris - poor in financial resources and rechnology but very rich in biological diversity. In these countries the so-called appropriate biotechnologies may become "windows of opportunities" for the characterization, conservation and use of such diversity. It is urgent, however, that these countries create conditions and capacities to characterize, conserve and use their resources in the short term.