Effects of the hormonal application on seed germination and seedling growth of the some Sorbus L.(mountain ash) species

In this study the effects of the phytohormones on seed germination andseedling growth of Sorbus domestica L., S. torminalis (L) Crantz and S.aucuparia L. were investigated in open area condition and climate chamber. Inopen area condition, the seeds stratified for 150 days and prechilled for 12 hoursby using 0, 250, 500, 750 ppm of GA3 and 0, 50, 150, 300 ppm of IBA, weresowed at Gölköy Forest Nursery.After the 150 days? stratification, the radicule emerged seeds were pretreatedby using 0, 250, 500, 750 ppm of GA3 for 1-4 hours and sowed to theexperiment site of Kastamonu Forestry Faculty.In the climate chamber, 0, 250, 500, 750 ppm doses of GA3 were applied to the150 days? stratified seeds of S.domestica. At he same time, 0, 750, 1500, 3000doses of GA3 were applied to the non-stratified seeds of S. domestica. All theseeds were keeped in above concentrations by 12 hours and sowed in thechamber (15000 lux of light for 16 hours and darkness by 8 hours, 20 ±2 0Ctemperature, 70% of humidity).For determining, the phytohormone effects, germination percentage, seedlingheight, hypocotyl length parameters were measured.In the sowing experiments at Gölköy Forest Nursery, the germinationpercentage was only obtained for S. domestica at the rate of 1-2%. Nogermination was obtained for the other species. In the seeds stratified for 150days, 30-35 % of germination percentage for S. torminalis and 3-4 % ofgermination percentage for S. aucuparia were observed at the end of thestratification stage.In the climate chamber, the highest (29%) germination percentage was obtainedfor the application of 3000 ppm GA3 on the non-pretreated seeds of S.domestica. On the same seeds, 9 % and 1,3% of germination were obtained for750 ppm and 1500 ppm GA3 application, respectively. Also, no germination wasobtained in the control seeds. In the 150 day?s pre-treated seeds, the highestgermination percentage was obtained in the application of 750 and 500 ppm as8%. Also, 5,3% of germination was obtained in control.In the S. domestica seeds, of which radiculi emerged and applied GA3 at 0, 250,500, 750 ppm doses, the highest seedling height was obtained for 750 ppm as60,66 mm. Also, the lowest seedling height was obtained for control. Hypocotyllength was obtained as big as 2 times (16,8-18,9 mm) than the control (8,8 mm)in phytohormone application.Key Words : Sorbus,Germination,Seedling,Pre-treatment,Phytohormone