Effect of dopamine hormone application on germination characteristics of seeds of some Anatolian Black Pine (Pinus Nigra J.F. Arnold Ssp. pallasiana (Lamb.) holmboe) origins germinated under drought stress

Forests, which are indispensable ecosystems for living beings, have been under serious pressure due to global warming and drought in recent years. black pine is one of the most important species used in afforestation studies in our country. The selection of tree species and origins for the rational use of water is of critical importance for a sustainable management approach. Dopamine (DOP) supports plant growth and development by interacting with phytohormones. With the thesis research, DOP substance application was carried out on forest tree seeds for the first time. In this study, it was aimed to determine the effects of external dopamine application on different drought stress levels in terms of germination parameters (germination percentage, average germination time, germination speed and germination value). within the scope of the study, origins from 10 different seed stands of black pine seeds (İzmir / TM-100; Kahramanmaraş / TM-114; Zonguldak / TM-140; Çanakkale / TM-329; Ankara / TM120 / tm123; Bursa / TM83; Kastamonu / TM131; Balıkesir / TM118; Eskişehir / TM117) were selected. 3 different drought stress levels -0.4 MPa (Peg4), -0.6 MPa (Peg6) and -0.8 MPa (Peg8) and 3 different doses of dopamine hormone (0.5 mM, 1 mM, 1.5 mM) were applied. As a result, it was found that there were decreases in germination parameters with the increase in drought stress level. It was found that the applied dopamine hormone had a positive effect in terms of germination parameters, especially at Peg4 and Peg6 levels, reducing the negative effects of drought. Especially, the effect of DOP 0.5 mM and 1 mM dose applications on seed germination parameters was found to be significant.