Su Stresi Altındaki Bazı Kızılçam Kaynaklarının Tohum Çimlenme Oranı ve Fidelerin Gaz Değişim Performanslarının İncelenmesi

Abstract

With climate change, global warming has increased adverse effects on living things in our country. In these adverse effects, water scarcity is the most crucial problem due to the increase in temperature and decrease in precipitation. Forests are the most affected ecosystem among others by water scarcity in our country. This study tried to determine the 5-year-old seeds and 1-year-old seedlings (produced from the same seeds) of some Turkish red pine provenance’ responses to different water stress levels. First, how the water stress levels (0, -0.2, -0.4, -0.6, -0.8 MPa) affect seed germination of these provenances was determined. Secondly, gas exchange parameters [net photosynthesis (Anet), stomatal conductance (gs), transpiration (E), and intrinsic water use efficiency (iWUE)] under different water stress were determined in the seedlings obtained from these species' seeds. As a result of the germination test, Denizli-Çameli (DC) provenance had the highest rate (48%), while Maraş-Suçatı had the lowest rate (29%) under control treatment. The highest germination rate was obtained in Burdur/Bucak provenance (5%) under -0.2 MPa osmotic potential. For gas exchange parameters, Antalya/Gündoğmuş provenance had the highest Anet, gs values while DC provenance had the lowest Anet, gs, and E values when provenance is considered as a single factor. Besides, increasing in irrigation increased Anet, gs, and E while decreased the iWUE. The lowest seedling E under water stress can be explained because this species responds to the water shortage by closing its stomata. Among the Turkish red pine origins, DC provenance showed higher drought tolerance than others.