The storage of seeds in seed banks is a primary strategy for plant conservation in the face of unprecedented biodiversity loss. For seeds of wild species, the effective and evidence-based curation of collections is an ever-increasing challenge as the size and diversity of the collections grow. For example, the Department of Biodiversity Conservation and Attractions and Kings Park and Botanic Gardens in Western Australia are jointly responsible for >16,000 accessions of >3,500 wild species, including sole remaining wild populations and some collections that represent populations now extinct in the wild.
However, a number of phenomena are only now becoming apparent as data accumulate regarding the behaviour of desiccation tolerant seeds of diverse species that have been stored and monitored over a number of decades in seed banks globally: (1) For an increasing number of species there are anomalies in the relationship between storage temperature and seed longevity and storage at colder temperatures does not translate to greater longevity; (2) Even for seeds with orthodox storage behaviour, their longevity is not as expected or predicted for many species and; (3) The variation in seed longevity, both within and between collections of a particular species, can be vast – up to orders of magnitude, even for relatively genetically uniform crop species.
This new evidence challenges the premise that seed banking offers extinction-proofing of wild, diverse species through storage of viable germplasm over decades and centuries. In this presentation I will discuss some of our recent work investigating the utility of measuring metabolic rates (MRs) for stored seed to better understand viability and longevity for wild species. We hope that with further technological refinement we can utilise metabolic measurement to predict longevity and monitor viability loss in an efficient and accurate manner.