Wagner Vendrame and coworkers at the University of Florida in Homestead http://trec.ifas.ufl.edu/vendrame/index.htm are doing research on cryopreservation of orchid seed and pollen at liquid nitrogen temperatures. They have recently published some papers on these topics:
Vendrame, W.A., V.S. Carvalho, J.M.M. Dias, and I. Maguire. 2008. Pollination of Dendrobium Hybrids using Cryopreserved Pollen, HortScience 43(1): 264-267 . Vendrame, W.A., V.S. Carvalho, I. Maguire and J.M.M. Dias. 2007. In vitro germination and plant regeneration of cryopreserved Dendrobium hybrid mature seeds, Scientia Horticulturae 114:188-193. I recently sent them a large batch of Stanhopea seed, which has notoriously short viability under typical storage conditions. They are trying various storage techniques to see if Stanhopeinae are amenable to storage under liquid nitrogen conditions. It seems to me that any serious seed banking effort needs to move towards this type of technology, rather than storing seeds at 4 C. If seeds can tolerate the cryopreservation/thawing proceedures, storage at liquid nitrogen temperatures renders the seed essentially immortal, with little or no loss in viability. And since orchid seeds are so small, they are relatively cost-effective to store in liquid nitrogen relative to other plants with larger seeds. Mark Whitten Florida Museum of Natural History
_______________________________________________ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
