Grevillea batrachioides has only recently been rediscovered after being presumed to be extinct. P.Olde Problems Initiation of plant material into the tissue culture environment is always a difficult process and, as plant material from the wild has a high natural microbial presence, it is essential to only use healthy actively growing shoots. Growing plants in a protected environment, such as a glasshouse for several weeks prior to initiation, decreases contamination considerably at this stage and is the recommended method. It is common in new explants and may be overcome with subsequent subculturing, although some species take up to 12 months to outgrow this problem. We have also had success using vented lids which reduce the relative humidity of the jar.
Tissue culture is an appropriate ex situ conservation technique for some species.
In recent times we have embarked on a number of projects in which tissue culture may play some role, most notably ex situ conservation of the endangered Wollemia nobilis . Tissue culture techniques developed at Mount Annan are now being used to propagate this species for the commercial market. As a young botanic garden our role is continually developing, however, it is certain that micropropagation of threatened species will be a valid technique in insuring against species loss, if it is seen as part of an overall strategy. Rare or threatened Australian plants . CSlRO Publishing, Australia.