Effects of cold stratification and sulphuric acid pre-treatments on germination of pomegranate (Punica granatum L.) seeds in greenhouse and laboratory conditions

Abstract

This study was carried out to determine the effects of some pretreatments including soaking in concentrated (98%) H2SO4 for 10, 20, 30, 40 and 50 min and cold stratification (at 4±1°C) for 15, 30, 45 and 60 days followed by soaking in H2SO4 for 10, 20, 30, 40 and 50 min on seed germination and to investigate how to overcome dormancy of Punica granatum L. seeds. The seeds were sown in polyethylene pots in the greenhouse and sown at 22±1°C under darkness in laboratory conditions. The statistical approach was a randomized complete block design with three replications. Germinated seeds were observed periodically during 50 days to determine germination percentages and germination rates. Soaking in H2SO4 for 30 min with cold stratification for 45 days gave the highest germination percentage (60.7%) in the laboratory while, the highest germination percentage (85.5%) was obtained from soaking in H2SO4 for 40 min with 30 day cold stratification pre-treatment although there were not any significant differences for germination percentages between pre-treatments in the greenhouse. In addition, the best germination rate (21 days) was obtained from the seeds which were soaked in H2SO4 for 30 min with 45 day cold stratification and soaked in H2SO4 for 40 min with cold stratification for 45 days pre-treatments in the greenhouse. Key words: Dormancy, germination, pre-treatment, Punica granatum, seed.