Spore germination of Gleichenella pectinata (Willd.) Ching (Polypodiopsida-Gleicheniaceae) at different temperatures, levels of light and pH

Abstract

This study investigated the effects of different temperatures (25 and 30 ± 2 ºC), light levels (62, 42, 22 and 5% of natural light), and pH (4.0, 4.5, 5.0, 5.5, 6.0 and 6.7) 22 and 5% of natural light (8.8 ± 2.3% and 11.3 ± 2.2% respectively) and the highest percentage of heart-shaped gametophytes were observed at pH 4. 5 and 5.0 (1.2 ± 0.8% and 2.2 ± 0.8%, respectively).

Abiotic environmental conditions for germination and development of gametophytes of Cyathea phalerata Mart. (Cyatheaceae)

“…Brum & Randi (2002) observed that the best method of decontamination with the highest percentage of germination for Rumohra adiantiformis (Dryopteridaceae) was using 15 % of a commercial NaClO solution (containing 2 % active chlorine) for 10 min plus supplementation of the culture medium with Benomil (Benlate ® ). Sterilization of spores using NaClO combined with the addition of Benlate ® to the culture medium has been successfully employed for in vitro cultivation of fern species (Brum & Randi 2002;Viviani & Randi 2008;Santos et al 2010). However, it has been illegal to sell this fungicide in Brazil since 2001.…”

“…Herbaceous fern species also exhibit elevated germination rates in acidic pHs, including Ophioglossum palmatum (Ophioglossaceae) (Whittier & Moyroud 1993), Cheilanthes feei (Pteridaceae) (Nondorf , Polypodium lepidopteris (Polypodiaceae) and Gleichenella pectinata (Gleicheniaceae) (Viviani & Randi 2008;Santos et al 2010). Notwithstanding, some species of ferns exhibit low germination percentages or are even incapable of germinating in highly acidic substrates (Hevly 1963), like Anemia mexicana and A. phyllitidis (Schizaeaceae) (Nester & Coolbaugh 1986).…”

Propagación in vitro de Cyathea atrovirens (Cyatheaceae): almacenamiento de esporas y condiciones de esterilización

“…The surface sterilization of spores with NaClO associated with the addition of the fungicide Benlate® (benomyl) to the nutrient medium has been used as an alternative to eliminate contamination of fern cultures in Brazil (Renner & Randi, 2004;Brum & Randi, 2006;Begnini & Randi, 2009;Viviani & Randi, 2008;Santos et al, 2010). However, this fungicide is not a viable alternative, since it is no longer available in the market of this country.…”

“…Storage conditions under different temperatures have been tested focusing on the survival and germination of spores (Simabukuro et al, 1998;Rogge, Viana & Randi, 2000;Quintanilla et al, 2002;Begnini & Randi, 2009;Santos et al, 2010). The viability of spores from different species has been investigated after cold storage (for a revision, see Ranker & Haufler, 2008), and low temperature was considered as minimizing bacterial and fungal contamination without decreasing spore viability (Quintanilla et al, 2002).…”

“…Among antibiotics that can be used to avoid the in vitro contamination of plants (Kyte & Kleyn, 1996), Micostatin® (Ranal, 1991), nystatin (Dyer, 1979;Simabukuro et al, 1998;Quintanilla, Amigo, Pangua & Pajaron, 2002) and streptomycin (Cox, Bhatia & Ashwath, 2003) were tested for ferns, although without total elimination of the microorganisms from the cultures. The treatment of plant tissues with sodium hypochlorite, followed by the addition of the fungicide Benlate ® (Benomil -Dupont) to the culture medium has also been used for fern species (Brum & Randi, 2006;Begnini & Randi, 2009;Viviani & Randi, 2008;Santos, Lehmann, Santos & Randi, 2010). However, this fungicide had its manufacture discontinued since 2001 (Dupont, 2012).…”