150-seed comparative longevity protocol – a reduced seed number screening method for identifying short-lived seed conservation collections

Comparative seed longevity testing is a useful tool for setting appropriate germination test intervals for viability monitoring of ex situ conservation collections. A reduced seed number comparative longevity protocol, designed to screen for short-lived species and which uses only 150 seeds sampled at just four intervals during controlled ageing, at 2, 10, 15 and 30 days, was compared with the standard comparative longevity protocol of nine or ten sampling intervals using a total of either 450 or 500 seeds, respectively. Reduced seed number longevity test survival curves differed significantly (P < 0.05) from standard longevity test survival curves in only one of the 30 collections tested. Estimates of p ₅₀ for reduced seed number longevity tests were not significantly different from standard longevity tests. Adoption of this reduced seed number longevity test as a routine procedure in genebank management will identify conservation collections with potentially short-lived seeds and thereby reduce the risk of undetected viability loss. The reduced seed number longevity test will also reduce staff time and costs and use fewer seeds compared with standard seed longevity testing, thus enabling more effective management of conservation collections.