Longevity of Juniperus procera seed lots under different storage conditions: Implications for ex situ conservation in seed banks

Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses: modern cold room (5°C), mud house (15°C), concrete block house (17°C) or corrugated iron house (20°C) for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation (p < 0. 01) in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room (41%) and the mud house (38%) maintained the same level of germination as the intitial germination of the seedlotds (42%). The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots (r > 0. 80; p < 0. 01). Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deep physiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room (5°C) up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level. © 2011 Northeast Forestry University and Springer-Verlag Berlin Heidelberg.