title: Cryopreservation of spores of Dicksonia sellowiana: an endangered tree fern indigenous to South and Central America.
abstract: Spores of Dicksonia sellowiana (Presl.) Hook., an endangered tree fern, were stored in liquid nitrogen. Surface sterilized spores were placed in 1 ml sterile polypropylene cryotubes and were plunged into liquid nitrogen cryo-cans for 15 minutes, 15 days, 1 month and 3 months. In all, of the treatments the percentage of germination was higher than the control (fresh spores). Germination in Dyer and MS media supplement with 10 (-7) M and 5 x 10(-7) M BA was also promoted as comparing to control. There was no difference between the germination of spores thawed rapidly in a water bath at 45 degree C during 5 minutes or slowly at room temperature. Cryopreservation seems to promote germination of some dormant spores of D. sellowiana. The pre-treatment in cryoprotective solution of dimethyl sulphoxide 15%(v/v) in 1 M glycerol inhibited the germination of cryopreserved spores
authors.affiliation: Departamento de Bot nica, Universidade Federal de Santa Catarina, Florian polis, SC,CEP 88040-900- Brazil.
authors.forename: G D
authors.initials: GD
authors.lastname: Rogge
authors.forename: A M
authors.initials: AM
authors.lastname: Viana
authors.forename: A M
authors.initials: AM
authors.lastname: Randi