Comparative longevity of Australian orchid (Orchidaceae) seeds under experimental and low temperature storage conditions
MetadataShow full item record
Seeds from ten terrestrial orchid species, nine from the south-west Australian biodiversity hotspot (Caladenia arenicola, Caladenia flava, Caladenia huegelii, Diuris laxiflora, Microtis media ssp. media, Pterostylis recurva, Pterostylis sanguinea, Thelymitra crinita and Thelymitra macrophylla) and one from south-east Australia (Diuris fragrantissima), were placed into experimental storage to assess their relative longevity and likely optimal conditions for long-term conservation seed banking. Seeds from all species were desiccation tolerant, germinating after drying at 23% relative humidity (C. arenicola, C. huegelii, P. sanguinea and T. macrophylla) or 5% relative humidity (C. flava, D. laxiflora, M. media ssp. media, P. recurva and T. crinita) at 23 °C. From automatedly determined moisture adsorption and desorption isotherms at 23 °C, these equate to tolerance of drying to 0.03-0.06 g water g-1 dry weight or 0.013-0.028 g water g-1 dry weight, respectively. Results of storage experiments at a range of moisture contents and temperatures suggest conventional seed bank storage at -18 °C after equilibration at c. 23% relative humidity (at 23 °C) may be suitable for most of the species, although there was higher germination of P. recurva seeds stored at -80 °C and of M. media ssp. media seeds equilibrated at 75% relative humidity. However, there was considerable variation in germination of seeds sampled after different storage periods, making it difficult to identify optimal storage conditions definitively. Results of comparative longevity storage experiments at 60% relative humidity and 40 °C suggest seeds from these orchid species are short-lived compared with non-orchid species, and with Australian species in particular. © 2010 The Linnean Society of London.
Showing items related by title, author, creator and subject.
Seed moisture content affects afterripening and smoke responsiveness in three sympatric Australian native species from fire-prone environmentsTurner, S.; Merritt, D.; Renton, M.; Dixon, Kingsley (2009)Germination of freshly collected seeds of three sympatric herbaceous species native to fire-prone environments in south-western Australia was significantly improved through the application of novel combinations of dry ...
Germination responses of four native terrestrial orchids from south-west Western Australia to temperature and light treatmentsNikabadi, S.; Bunn, E.; Stevens, J.; Newman, B.; Turner, Shane; Dixon, Kingsley (2014)We report an investigation into the impact of temperature and illumination on in vitro symbiotic and asymbiotic germination of the threatened taxon Caladenia huegelii, and three other orchid spp. namely—Caladenia latifolia, ...
De Long, J.; Swarts, N.; Dixon, Kingsley; Egerton-Warburton, L. (2013)Background and Aims: Mycorrhizal specialization has been shown to limit recruitment capacity in orchids, but an increasing number of orchids are being documented as invasive or weed-like. The reasons for this proliferation ...