Effect of drought stress on some physiological and biochemical characteristics in Quercus petraea subsp. iberica seedlings and analysis of the relationship between morphological traits

Within the scope of the study, it was aimed to determine some physiological and biochemical characteristics of the saplings grown from seeds obtained from different populations of the North Anatolian sessile oak against drought stress, and to reveal both the reactions of the species to drought and the changes in reactions to drought depending on the populations. In this context, pre-dawn plant water stress, soil temperature and humidity, photosynthetic pigment analysis, total soluble carbohydrate and proline contents of sessile oak seedlings were determined. In addition, some morphological features were measured in one-year-old sessile oak saplings, and the relationships between the reactions of populations to drought stress and morphological characteristics were evaluated. As a result of the study, it was determined that there are differences between the populations in terms of both physiological and biochemical characteristics and morphological characteristics. On the other hand, it was determined that due to the increase in the stress application period in the saplings exposed to drought stress, the plant water stress, total carotenoid, proline and total carbohydrate amounts increased, while chlorophyll a, b and total chlorophyll amounts decreased. Also, in terms of morphological characteristics, variations between populations were revealed and it was determined that there were strong relationships between the physiological and biochemical responses of the populations to drought stress with the data obtained from dry root percentage, sturdiness index, dry shoot-root ratio and Dickson quality index, which are important parameters in seedling quality classification.