Physical and Chemical Treatment Effects on the Germination of Pear Seeds (Pyrus Communis L.)

Pear (Pyrus communis L.) is one of the important species of fruits that are widely cultivated in Syria. Seed propagation of the pear is an important way to obtain seedlings to be used as grafting assets, but the method of seed propagation is difficult due to the effect of dormancy factors in germination. The research was carried out during 2020 and 2021 to study the effects of stratification for three periods (30–60–90 days) using ascorbic acid at a concentration of 100 mg/L, and potassium nitrate at a concentration of 0.3% for breaking the dormancy of pear seeds. The results showed that the best averages were at stratification for 60 days and gave the percentage of germination as 31%, and the speed of germination at 1.28 seeds/day. Additionally, treatments of seed soaking with ascorbic acid or potassium nitrate (without stratification) contributed to improving the germination percentage to 7.67% and 3.67%, respectively, with significant differences compared with the control (1%). The best results were with stratification treatment for 60 days with ascorbic acid, where the percentage of germination reached 49.67% and the germination speed increased to 3.91 seeds/day, in addition to reducing the period required for germination to 21 days.