Effects of GA3 and Stratification on Seed Germination of Field Maple (Acer campestre L.)

Dormancy breaking of field maple (Acer campestre L.) seed، by gibberllic acid (GA3) at 0، 250، 500 and 1000 ppm in 24 and 48 hours and stratification treatments in moist sand under warm (18-20 °C) and cold (2-4°C) conditions were investigated. Effects of GA3 and stratification and their interaction on germination percent (GP) and germination speed (GS) were significant. The highest GP occurred at warm (12) (53%) and warm (8) (38%) without GA3، and at warm (12) with 1000 ppm GA3. At treatments with and without GA3 combined with cold stratification (34 weeks) no germination appeared. The highest GS allocated to warm of 12 without GA3، and then in such stratification combined with 1000 ppm GA3 (24 and 48 hours). At 500 and 1000 ppm GA3، the GS enhanced with increasing warm stratification period and decreasing cold stratification period. This research implies that stratification of A. campestre seed under 12-22 weeks warm-cold stratification is a relatively good treatment to remove dormancy. Continuation of experiment with longer periods of warm stratification or with some seed germination-promoting hormones may be resulted in better breaking dormancy of A. compestre seed.