Affiliation:
1. University of Santa Catarina, Brazil
Abstract
Light is a limiting factor for fern stablishment because it controls germination of light sensitive spores. The aim of this work was to study the effect of light levels on spore germination in two ornamental ferns native to the Atlantic forest, under natural conditions. Cyathea delgadii is a tree fern and Blechnum brasiliense, a subarborescent fern. The effect of light levels was analyzed in April and July/2003, in Florianópolis, Santa Catarina state, Brazil. Sterilized spores were sown in Erlenmeyer flasks containing mineral culture medium with macronutrients, iron, and benomyl 0.01%. The Erlenmeyer flasks were kept in 50 cm³ boxes covered with black shade netting, which gave 5, 22, 42, and 62% natural light. Irradiance and temperature were scored daily at 14:00 h during the study period. Higher percentages of germination were observed at 5 and 22% light for both species. Germination of Cyathea delgadii spores at 22% light reached 76% and mean germination time was 19.7 days; at 5% light, germination reached 83.5% and mean germination time was 20.16 days. Germination of Blechnum brasiliense at 22% light reached 76% and mean germination time was 9.06 days; at 5% light, germination reached 84% and mean germination time was 13.18 days. The highest light levels inhibited spore germination and the gametophytes died during the test period.
Reference33 articles.
1. Seeds: physiology of development and germination;Bewley J.D.,1994
2. Tree ferns in the interior and at the edge of a Mexican cloud forest remnant: spore germination and sporophyte survival and establishment;Bernabe N.;Biotropica,1999
3. High irradiance and temperature inhibit the germination of spores of the fern Rumohra adiantiformis (Forst.) Ching (Dryopteridaceae);Brum F.M.R.;Revista Brasileira de Botânica,2002
4. Photosynthetic light environmental in a lowland tropical rain forest in Costa Rica;Chazdon R.L.;Journal of Ecology,1984
5. Photoprotection and other responses of plants to high light stress;B. Demming-Adans;Annual Review of Plant Physiology and Plant Molecular Biology,1992
Cited by
17 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献