Effects of some pre-sowing treatments on germination of Crataegus monogyna seeds under greenhouse condition

This study assessed the effects of pre-sowing treatments used to break dormancy of hawthorn (Crataegus monogyna) seeds collected from three provenances: trees growing at sea level, low altitude and high altitude. This experiment was based on a factorial design with three factors: eight pre-sowing treatments, three provenances, and three seed harvesting times. Seeds were treated with warm stratification at 25 degrees C, cold stratification at 4 degrees C, soaking in hot water (38 degrees C) for 10 days or soaking in 500 mg L-1 polystimulins (PS A6-auxin + PS K-cytokine) for 24 hours before sowing. Hormone application followed by warm and cold stratification was very effective in breaking seed dormancy and accelerated the metabolism of hawthorn seeds. The best results (85%) were recorded when seeds were treated with 500 mg L-1 PS-A6 + PS-K followed by warm stratification for 45 days and cold stratification for 180 days. Germination was enhanced in seeds from a lower altitude provenance. These results suggest that the application of polystimulins followed by alternating temperature stratification (both warm and cold stratification) is effective at breaking the dormancy of hawthorn seeds.