Özet:

Abstract − Plant-derived smoke has been shown to trigger germination of many Lamiaceae species growing in Mediterranean-type ecosystems. However, very little is known about the germination response of Lamiaceae species to smoke-derived compounds, such as karrikinolide (KAR1) and cyanohydrin. In this work, therefore, we aimed to ascertain the effects of smoke-derived compounds on seed germination in seven Mediterranean Lamiaceae species (Ballota acetabulosa, Lavandula stoechas subsp. stoechas, Origanum onites, Phlomis bourgaei, P. lycia, Stachys cretica subsp. smyrnaea, and Teucrium chamaedrys). To achieve this goal, seeds of study species were exposed to different concentrations of smoke-water, KAR1, mandelonitrile (MAN), and KAR1 + MAN. Seeds from treatment groups were then incubated at 20 °C in dark conditions, and germination counts were made twice weekly for 35 days. Our results show that smoke leads to a significant increase in germination percentage of B. acetabulosa, P. lycia, and S. cretica as compared to control conditions. KAR1 stimulated the germination of B. acetabulosa and S. cretica while MAN treatments did not promote the germination of Lamiaceae species. The combination of KAR1 and MAN not only induced the germination of three smoke-sensitive species but also notably increased the germination percentage of T. chamaedrys. In conclusion, our study supports the idea that smoke has a positive impact on the germination of Lamiaceae species and provides evidence that combined application of KAR1 and cyanohydrin is more effective in the stimulation of seed germination than the separate application of these two compounds.