Effects of tegument, endosperm, cold treatment and harvest date on germination of wild olive

Wildolive seeds (Olea europaea L. var. sylvestris), calledoleaster do not germinate when placedunder favourable conditions. In a series of experiments the effects of the harvest date, the endosperm, the tegument, andthe coldtreatment were evaluatedon germination of seeds andembryos. The germination percentage of embryos and seeds harvested at different harvest dates increased during October month, these percentages decreased during November month, whereas no seeds and embryos harvested on the middle of December germinated. Embryo germinability was always higher than seed germinability, and this may be due to an inhibiting effect of the teguments and the endosperm on seed germination. Such dormancy, which gradually increased during maturation, could reside mainly in the endosperm and partly within the embryo. The cold treatment at 4°C for four to thirteen days increased seed and embryo germinability, whereas lengthening time at this temperature showeda negative effect on seedgermination. The germination of seeds andembryos from six wildolive trees was also examinedby recording the germination percentage andminimum imbibition time (Tmi).