With the purpose of providing a basis for programs of sustainable management in the conservation of this endangered species, this paper presents morphological aspects on the gametophyte development of Dicksonia sellowiana (Dicksoniaceae) by light microscopy and scanning electron microscopy. Dicksonia sellowiana spores were germinated in Morh's nutrient solution modified by Dyer (1979) under a 16-hour photoperiod at 23 ± 2°C. To determine the best substrate for gametophyte and sporophyte development, 30 days after spore sowing filamentous gametophytes were transferred to different substrates: soil rich in organic matter; coxim (coconut fiber); sterilized typic hapludult soil (distroferric red nitosoil); and sterilized typic hapludult soil (distroferric red nitosoil) with the addition of organic compost. The best system for D. sellowiana growth was the red soil with the addition of compost. Fifteen days after spore sowing in mineral solution, gametophytes were filamentous. Some had attained laminar morphology and had established an oblique cell division, giving rise to the obconic cell. Laminar gametophytes were observed 30 days after spore sowing and cordate gametophytes were observed after 45 days. Mature cordate gametophytes were observed after 80–90 days. After 245 days 84.67% of gametophytes had produced sporophytes in sterilized red soil with the addition of organic compost. In typic hapludult soil, without the additional termophilic compost, sporophyte formation was delayed (development after 180 days). When gametophytes were transplanted to soil rich in organic matter they did not develop and in the “coxim” substrate, which is a substitute for the “xaxim” substrate, only filamentous gametophytes were observed at the end of the study.
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Dicksonia sellowiana
gametophyte development
substrate comparison