Physiology characteristics and storage of hopea odorata seeds

Hopea odorata is a large tree species with high economic value that prevails in tropical evergreen rainforests. This is one of few large-timber indigenous species named on the Vietnamese list of major species forafforestation in Vietnam. However, its fruiting occurs very erratically. Seeds are typical tropical recalcitrant and have rapid loss of viability. Thus, study on physiology characteristics and storage of Hopea odorata seeds is essential to have sufficient knowledge for propagation, biodiversity conservation and plantation development. The results showed that the average number of fruits per kilogram were 3093 and mean seed fresh weight at collection was 0.32gram. Moisture contentof fresh seeds was 51% and the germination rate was 96.5%. Seed germination started onthe 1stday, reached the highest rate on 2nddayand endedon 14thday. Seed germination rate reduced significantly from 96.5 to 85% when moisture contentwas reduced respectivelyfrom 51to 35% and dropped to 0% at moisture content of 8%. Critical moisture content of Hopea odorata seeds was 35%. The highest germinate ratewas at room temperature(27–32oC). Seed viability could maintain till 150 days at storage temperature of10°C.