Seed storage behaviour of Magnolia odoratissima

Magnolia odoratissima is endemic to Yunnan Province in southwest China. The flowers and leaves contain approximately 0.2% aromatic oil, making it an excellent perfume plant. However, the species is now facing an extremely high risk of extinction in the wild and has been proposed as a critically endangered tree. To effectively preserve its germplasm via seeds, we studied the effects of moisture content and storage conditions on seed germination. The 1000-seed weight, initial moisture content and germination of fresh seeds were 184.0 g, 33.2% and 98%, respectively. Most of the seeds tolerated desiccation to 21.6% moisture content, while more than half of the seeds lost viability when dried to 14.1% and only a few seeds (21-28%) survived when the moisture content was reduced to 9.9%. Therefore, M. odoratissima seeds showed intermediate storage behaviour. Non-desiccated seeds retained viability at storage temperatures of 4, 8 and 20 degrees C. However, the viability of both air-dried and pre-chilled seeds stored at 4, 8 and 20 degrees C was reduced with prolonged storage time. The seeds stored for all treatments at -20 degrees C lost viability. The data consequently suggest that M. odoratissima seeds are chilling-tolerant intermediate seeds which can be stored at 4 degrees C for up to one year.