EN
The present paper examines the germination requirements of the seeds of two woody species (Koelreuteria paniculata and Mahonia aquifolium). Koelreuteria paniculata seeds were subjected to a combination of acid scarification, gibberellic acid (GA3) and cold stratification treatments. Un-scarified seeds, which were only cold stratified (up to 3 months) as well as the seeds which were only acid-scarified (up to 60 minutes) exhibited low germination percentages. The combination of sulphuric acid scarification and cold stratification treatments significantly improved germination. In acid-scarified seeds, GA3 application improved germination, but did not fully replace the cold stratification period required to break seed dormancy. Mahonia aquifolium seeds were subjected to a combination of GA3 and cold stratification treatments. Notably, prolonged cold stratification is essential for the germination of M. aquifolium seeds since seeds stratified for 1 or even 2 months did not germinate. In almost all cases, the percentage of M. aquifolium seeds germinated was higher with GA3 treatment applied prior to cold stratification than with cold stratification only.