Conserving Australia's unique rainforest fruits and wild relatives

Australian rainforests have many unique edible fruits including wild relatives of worldwide economically important species such as citrus and macadamia. One of the key risks of projected climate change is its effect on Eastern Australian rainforests. The interaction of climate change with other threats, such as weeds and habitat fragmentation, is thus likely to impact on already vulnerable environments such as the World Heritage listed Gondwana Rainforests of S. Queensland and N. New South Wales. Seed banking is a cost effective way of conserving unique and vulnerable diversity ex situ for utilisation (e.g., plant breeding and restoration programs). However, the seeds of many rainforest species cannot survive the desiccation required in standard seed banking procedures (i.e., non-orthodox seed storage characteristics). This paper reports on preliminary findings on biology and storage characteristics of seeds of 11 significant and/or threatened Australian rainforest fruits. Of these, 4 were desiccation sensitive (DS) and living collections and technology development (e.g., cryopreservation) needs to be prioritised for ex situ conservation. Of the 7 desiccation tolerant (DT) seeds, only one is expected to be viable in long-term storage by standard seedbanking methods. The oil content and thermal analysis of oils is described for 5 of these species and indicates the need to investigate alternative storage, particularly cryopreservation, for these species.