Dormancy and viability of Litsea glutinosa seeds

Litsea glutinosa, an important medicinal and economic plant, produces seeds that have low germination on shedding. The causes of low germination, the type of dormancy, and the effect of post-harvest storage on survivorship and dormancy also remain unexplored. The study on seed pre-treatments found that a combined treatment of hot water and gibberellic acid (500 ppm) resulted in a maximum germination of 67.8%. Fresh seeds were stored at four seed moisture contents and three temperatures. Seed germination and viability tests were conducted at intervals up to 21 months after harvest to assess dormancy loss and seed viability. Analyses of data indicated that both dormancy and viability were affected by temperature and seed moisture content in storage. Viability was completely lost or reduced in seeds stored with about 8 to 13% seed moisture content at 30 and 40°C within 8 months of storage. At 15°C, no seeds germinated with all seed moisture contents tested due to dormancy, and viability remained unaffected for up to 6 months of storage. Dormancy loss was optimized after 8 months of storage in the viable seeds of all treatments, where seeds stored with 3 to 6% moisture contents at 30 and 40°C and 3 to 13% moisture contents at 15°C showed maximum germination. Secondary dormancy was imposed after this period. These findings support the existence of physiological dormancy in the seeds of L. glutinosa. The results have significant implications for propagation and/or conservation, helping to overcome seed dormancy between collection and their use in nursery production or regeneration efforts.