M.Sc. Tezi Görüntüleme

Student:	Hülya TORUN
Supervisor:	Assoc. Prof. Dr. Faik Ahmet AYAZ
Department:	Biology
Institution:	Graduate School of Natural and Applied Sciences
University:	Karadeniz Technical University, Turkey

Title of the Thesis:	THE EFFECT OF 24-EPIBRASSINOLIDE APPLIED AS FOLIAR ON SOME PHYSIOLOGICAL AND BIOCHEMICAL CHANGES DURING DROUGHT STRESS IN Ctenanthe setosa (Rosc.) Eichler
Level:	M.Sc.
Acceptance Date:	2/9/2005
Number of Pages:	69
Registration Number:	i1643

Summary:

It is known that environmental conditions affect plants adversely. So, researchers focus their studies on this issue. To remove or alleviate stress conditions, some growth regulating substances are applied to plant and how these substances show their effects on stress is studied for this purpose. In this study, which has searched how 24-epibrassinolide (EBl) in different concentrations through the drought period and what kind of effect is produced has been observed in control plant. Produced photosynthetic pigment quantities, enzyme activities such as superoxide dismutase (SOD), peroxidase (POD) and polyphenol oxidase (PPO), and malondialdehyde has been determined.

It was observed that total chlorophyll content decreased in stressed plants, while pigment content increased EBl-treated plant in comparison with stressed plants. It was recorded that activity of superoxide dismutase descended in stressed plants in comparison with control. However, the activity ascended again in EBl-sprayed plants. In addition, there was an obvious increase in POD activity in control plants in comparison with stressed ones. This result was opposite to activity results of SOD. Polyphenol oxidase activity decreased, which was similar to SOD activity, on the other hand the activity increased again in EBl-sprayed plant. As a determiner of lipid peroxidation content of MDA exhibited an important increase. However, it was noted that MDA lessened in EBl-treated plants.

For all studies, there was a common point that when EBl applied to control plant, it was observed that EBl has all result increased. At the end of the anatomic studies, it was determined that leaf rolling resulted from hypoderm layer, which was found below in epidermis and which shrinked because of water loss.

As a result, it is determined that EBl which is growth regulating substance delays leaf rolling.

Keywords: Drought, 24-Epibrassinolide, Photosynthetic Pigments, Superoxide Dismutase, Peroxidase, Polyphenol Oxidase, Lipid Peroxidation