Showing papers on "Lygodium published in 2007"

Myrothecium verrucaria – a potential biological control agent for the invasive ‘old world climbing fern’ (Lygodium microphyllum)

Abstract: One of the greatest threats to the native ecosystems in any part of the world is the invasion and permanent colonization of ecosystems by non-native species. Florida is no exception to this biological invasion, and is currently colonized by an extensive variety of exotic plant species. Originally imported from Asia over 30 years ago, Old World Climbing Fern Lygodium microphyllum (Cavanilles) R. Brown) has become one of the most invasive and destructive weeds in southern Florida. To date different effective control measures of its growth and spread have not been successful; fire and herbicide applications that are currently employed are neither cost effective nor envi- ronmentally friendly. In light of the highly delicate ecosystem that is being affected by L. microphyllum, we tested the soil fungus Myrothecium verrucaria (Albertini and Schwein) Ditmar: Fr. for its pathogenicity on the invasive fern. In greenhouse studies the effect of two conidial concentrations of M. verrucaria on L. microphyllum was investigated. Plants were spray inoculated with M. verrucaria which resulted in suc- cessful disease development with leaf necrosis symptoms. The higher conidial concen- tration (1 10 8 ml )1 ) produced a disease index of approximately 3 on a scale of 0 to 4, day 24 postinitial inoculation, demonstrating the efficacy of this fungus as a severe retardant of Lygodium growth. Preliminary screening of selected native plant species for susceptibility to M. verrucaria showed low disease indices after repeated spray inocu- lations; the highest index attained was 0.4 by Slash pine (Pinus elliottii).

Floristica e aspectos ecologicos da pteridoflora em tres segmentos florestais ao longo do rio Pindaiba, Mato Grosso

Abstract: Floristic and ecological aspects of the pteridoflora in three forest segments along Pindaiba River, Mato Grosso. The richness of pteridophytes in three forest segments along Pindaiba River: the first segment near the river’s source (municipality of Barra do Garcas), a second in the central region (Araguaiana) and one near the mouth (Nova Xavantina). A total of 26 species representing 13 genera and ten families, was found. The first and the last segments presented the biggest species richness (12 species). Pteridaceae presented the largest representation (seven species, 26,9%), while the smallest was wound in the Dryopteridaceae, Hymenophyllaceae, Psilotaceae and Selaginellaceae (one specie each). Larger generic diversity was observed in the Polypodiaceae (Microgramma and Polypodium), Pteridaceae (Adiantum and Pityrogramma) and Schizaeaceae (Anemia and Lygodium). The largest number of species was found in Adiantum, (six species: A. deflectens, A. humile, A. intermedium, A. latifolium, A. petiolatum and A. serratodentat um). Information related to the ecological aspects (habit, life forms and substrate preference) of the species is presented. The need for greater preservation of the forested areas along the rivers in order to conserve the fern flora is quite evident.

Fern inventorization in Laiwangi-Wanggameti National Park, East Sumba, Waingapu, NTT

Abstract: The inventory and the collection of the ferns in Laiwangi Wanggameti National Park will be plamted as collection plants in Bali Botanical Garden. In this research used the explorative method. The result of the research has collected 70 numbers of the ferns and 229 speciment. They consist of 21 family, 30 genus.and 70 species. From 70 species. There are 3 species such as Licopodium sernuum, Lygodium javanicum (Tumb.) Sw. and Ophioglossum pendulum L. are predicted as new collection for the Bali Botanic Garden. The dominant genus in Laiwangi- Wanggameti National Park was Cyclosorus, Asplenium, Athyrium, and Pteris. Which are growing to coverthe basic of the forest in damp places at the river bank.© 2007 Jurusan Biologi FMIPA UNS SurakartaKey words: inventory, collections, ferns, Laiwangi-Wanggameti National Park.

Relations between submarginal and marginal sori in ferns IV. The sori of Osmunda and selected Schizaeaceae and their morphological relations

Abstract: Developmental types of sori in Osmunda and Schizaeaceae are comparatively studied and discussed in a systematic context. (1) The ``simultaneous marginal sorus'' is characterized by a minute knob-like receptacle representing the thickened tip of a short costa, simultaneous initiation of massive sporangia, and absence of indusia. (2) The ``acropetal marginal sorus'' is characterized as an accessory outgrowth at the end of a costa or at the margin of a sorophore, comprising a minute or elongated bifacial receptacle, acropetal initiation of massive marginal sporangia, and minute or long-extended or hood-shaped upper indusia. The state of superficial singly-arranged massive sporangia such as in Todea may give rise to the Osmunda type of the simultaneous marginal sorus and to the Schizaeaceae types of the acropetal marginal sorus. Phase differentiation in leaf development combined with complete laminar reduction leads to the Osmunda type, while phase differentiation in leaf lamina development and additional processes may give rise to the Mohria, Anemia, and Lygodium types. These morphological results support recent phylogenetic studies by other authors in disclaiming close relationships between Osmundaceae and Gleicheniaceae, and between Marattiaceae and Ophioglossaceae (``Eusporangiatae''). They also potentially support relationships between Osmunda- ceae and Schizaeaceae or between Ophioglossaceae and Schizaeaceae. The high complexity of the sori in Marattiaceae and Ophioglossaceae is surprising if the two families are viewed as basal groups.