Preliminary study of the pre-germinative treatments of Juniperus oxycedrus L. and Pistacia lentiscus L. in the Saida region (Western Algeria)

Abstract Juniperus oxycedrus L. and Pistacia lentiscus L. are two taxa with a rigid or rigid enough structure caused by a solid pericarp resulting in a strong inhibition of the germination. The objective of this work was to test the effectiveness of certain pre-germinative treatments on the germination rate of the Juniperus oxycedrus and Pistacia lentiscus seeds with the aim of restoring perturbed ecosystems. In this context 180 seeds from each of the 2 examined species were tested in the laboratory (the number of repetitions is 5, to reach the degree of freedom 'ddl'). The seeds were divided into 4 groups of 20 seeds of each species and were treated as follows: 1) Immersion in the concentrated (95%) sulphuric acid (H2SO4) for 10, 30 and 60 minutes; 2) Mechanical scarification with a scalpel; 3) Soaking in hot water (at 100°C) for 30 seconds, 60 seconds and 2 minutes; 4) Cold stratification at 5°C for 24 hours. There is also a control group of 20 seeds representing each of the two species, which remained neutral. In the case of the Juniperus oxycedrus seeds the results showed that the germination rate improves after the mechanical scarification with a scalpel (92%), followed by the cold stratification with water (86%) and a treatment with a concentrated sulphuric acid for 60 minutes (82%). The seeds were treated with H2SO4 for 10 and 30 minutes, respectively, soaked in hot water; the control lot did not germinate. The germination rate for the Pistacia lentiscus seeds is 88% after the mechanical scarification and 84% after the cold water stratification. On the other hand, the treatment with H2SO4 or after soaking in hot water does not allow for the germination of these seeds. The same result is observed on the control group (0% for 30 days).