Seed dormancy in bay laurel (Laurus nobilis L.)

The germination of bay laurel (Laurus nobilis L.) seeds wasexamined both in the laboratory and in the field during twoyears. Seeds were collected from a grove in a garden in the townof Drama, Northern Greece, by mid November in the first year andby late November in the second year. The seeds with and withoutpericarp were given a warm-moist (20 °C day/12 °C night) oncold-moist (4±1 °C) treatment in peat or sand. After treatment theseeds were placed in the germinator along with controls. Thegermination of seeds with and without pericarp was alsoinvestigated in the field (late fall sowing). It was found thatthe pericarp caused dormancy. In seeds without pericarp,cold-moist and warm-moist stratification both proved to besuccessful in breaking embryo dormancy (100% and 96% successrespectively). The required stratification duration was 50 daysfor the warm-moist and 60 days for the cold-moist treatments.During the cold-moist stratification no germination was observed.On the other hand, seeds started to germinate during thewarm-moist stratification by about the 50th day. In the fallsowing germination was 20% for seeds with pericarp and 41% for seeds without pericarp. Drying bay laurel seeds caused areduction of the seed germination.