Germination of Arabequina Olive Seeds As Affected By Chemical Scarification, Hot Water Treatment And Endosperm Tissue

The effect of scarifying olive Olea europaea L. cv. Arabequina endocarp containing seeds (stony seeds) with H2SO4 and NaOH at two concentrations (0.1N and 1N) and two soaking periods (24 hrs and 48 hrs) as well as water for 24 and 48 hrs and hot water 50°C and 100°C for 24 and 84 hrs on their germination was investigated. To study the effect of the endosperm on seed germination, in vitro embryo culture of the same cultivar was performed. The germination potential of isolated embryos was compared to that of complete seeds and to sections of seeds including 2/3, 1/2, and 1/3 seed sections. The highest significantly germination percentage (60%) was obtained when the stone seeds were scarified with 0.1 N H2SO4 for 24 hrs after 115 days of planting. Treating the stony seeds with either H2SO4 for 24 hrs or water at 50° C and tap water for 24 and 48 hrs raised germination percentage over other treatments. Soaking the stony seeds with H2SO4 for 48 hrs improved germination percentage but with lower effect than H2SO4 for 24 hrs. The excised embryos and the 1/2 seed portion started to germinate after one week of culturing. The highest embryo germination percentage (70%) was recorded after one month of planting. Both 1/2 and 1/3 seed’s sections exhibited higher germination percentage than the germination of 2/3 seed section or whole seed. The results of this work indicated a pronounce effect of the endocarp and endosperm on olive seed germination