Seed treatment protocols for Hispaniolan pine (Pinus occidentalisSwartz [Pinaceae])

ABSTRACT:Hispaniolan pine (Pinus occidentalis Swartz [Pinaceae]) is an endangered tree species endemic to Haiti and the Dominican Republic. Species recovery is hindered by lack of reputable propagation knowledge, challenges associated with seed procurement, and limited resources available locally for propagation. A suite of germination and sanitation studies were conducted to examine the effects of seed moisture content, cold stratification length, and chemical treatment on germination. No evidence supports that the odds of a seed germinating are statistically different among seed moisture content levels, cold stratification lengths, or sanitation treatments. Mean germination time (MGT) was unaffected by seed moisture content but was greater when seeds were subjected to ≥ 14-d cold stratification compared to unstratified seeds. MGT was also greater when seeds treated with a 10-min soak in 2:3, 5.25% sodium hypochlorite:water solution followed by a 30-min running water rinse were compared to untreated seeds. Treatment with a 1-h 3% hydrogen peroxide soak followed by a 1-h running water rinse significantly reduced seedborne fungi in comparison to untreated seed. Results suggest that P. occidentalis has non-dormant seed and does not benefit from the current practice of a pre-germination soak or from cold stratification, but a 1-h 3% hydrogen peroxide soak followed by a 1-h running water rinse can control seedborne fungi without compromising germination.