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The density and frond traits of the dimorphic fern Osmunda regalis were examined in 45 populations situated in central Italy, along a gradient of forest canopy cover and deer grazing. The survey involved 1704 ramets containing 6416 fronds, of which 5643 were sterile and 773 fertile. Within the ramets, the number of fertile fronds increased with the number of sterile fronds and with the mean height of ramets. Light seemed to promote fertility, as the number of fertile fronds decreased with increasing canopy cover. Fewer and smaller fronds were found in plots with high forest canopy cover. Our results showed that O. regalis performed best in conditions of full sunlight but can persist and recruit young sporophytes under closed canopy. As many marsh and lake environments have disappeared or been altered by human activity, more populations were located under high canopy cover in the forest than in open habitats. Deer grazing caused a significant decrease in fertile fronds, in total frond area and in ramet height, but the number of ramets and sterile fronds were unaffected. In conclusion, plant density and frond traits of O. regalis responded differently to the availability of light and to grazing.
Among ferns, the leatherleaf fern (Rumohra adiantiformis) is of particular economic importance. The fronds are sold around the world for flower arrangements. In Brazil, these fern fronds represent an income source for numerous households, working with a traditional management system with a maximum of three annual collections in the same area. The purpose of this study was to evaluate the demographic structure of managed R. adiantiformis populations in the south of Brazil and verify the sustainability of the harvesting activity in this region. The study was conducted in an area of Atlantic Rainforest in the State of Rio Grande do Sul. The demographic structure of the managed populations was evaluated in permanent plots, where fronds in the different development phases were counted quarterly for one year. Rainfall was identified as the main factor influencing bud emergence and development. A reduction in R. adiantiformis populations related to forest regeneration was also observed. Fast frond regeneration and the absence of differences between managed and non-managed populations concerning the proportions of buds and young fronds corroborate the ecological sustainability of the management system used by the local harvesters. The results obtained differ largely from those of populations studied in South Africa, where R. adiantiformis plants seem unable to maintain frond density and size when harvested. These contrasting results are probably related to climatic differences between these areas, especially annual rainfall, which is higher in Brazil allowing for the rapid regeneration and sustainable management of this resource in the Brazilian Atlantic Rainforest.
The conservation of pteridophytes presents a demanding challenge because many species in the world are thought to be threatened with extinction, as they are very sensitive to environmental disturbance. Ex situ actions provide an important conservation strategy, so the Germplasm Bank of Tuscia Botanic Garden, with the Herbarium UTV (Tuscia University, Viterbo–Italy), has undertaken a project for the conservation of threatened pteridophytes of the Italian flora, like Osmunda regalis, the Royal Fern, a species with chlorophyllous spores that is declining in Italy because it is linked to vulnerable habitats. As a part of the project, this work presents first results of in vitro reproduction of the Royal Fern using spores from exsiccata (UTV samples collected and dried in 1989 and 2001). Our results also highlight the value of herbarium specimens in biodiversity conservation, providing a useful method to reproduce species that are threatened or extinct in the wild, at least at a local level, so as to plan eventual reintroductions using the native germplasm.
Selaginella apoda has many advantages as a model species, including a short life cycle. In order to work effectively with a lycophyte model species, it is important to be able to grow the gametophytes and sporophytes quickly. In the case of S. apoda, the gametophytes grow quickly and have high fertilization success in warm nutrient enriched water. Sporophytes at the three root stage can be easily transplanted to soil. They grow well in moist containers at a wide range of temperatures. Treatment with 0.15% Previcur®N prevents most fungal contaminations.
Three new species of Elaphoglossum sect. Polytrichia subsect. Hybrida from the Neotropics are described here: E. lucens, E. martinezianum, and E. reductum. The first species is characterized by blackish, lustrous and rigid rhizome scales and short fertile fronds. The second species is characterized by stipe and blade margins with long scales and blades elliptic and abaxially scaly. The third species is easy to recognize by small and curved scales and obovate blades. New geographic records are reported for three species, thus expanding their ranges.
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