Physiological, biochemical and molecular analysis of wheat cultivars under boron treatments


Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Fen Bilimleri Enstitüsü, Türkiye

Tezin Onay Tarihi: 2014

Öğrenci: CEYHUN KAYIHAN

Danışman: AYŞE MERAL YÜCEL

Özet:

Many studies have described the physiological, biochemical and molecular responses to boron (B) toxicity and deficiency individually in plants. However, overall pattern of gene expression changes and their physiological and biochemical significances after high B, low B and supplementing artificial B-enriched fertilizer (Tarımbor) application have not been proposed up till now. In the present study, we assessed global changes in gene expression of two wheat cultivars Bolal-2973 and Atay-85 differing in their B responses by using Affymetrix wheat GeneChip under B-toxicity, deficiency and Tarımbor applications. Another objective of this study was to clarify physiological and biochemical changes that are mainly related to growth, photosynthesis, antioxidants, antioxidant enzymes, water status and oxidative damage under same conditions. The visual symptoms of B-toxicity, regarding chlorosis and necrosis, were only seen in leaf tips of Atay. Coordinately, B accumulates higher in Atay leaves than Bolal at the end of the B-toxicity. However, all B conditions did not cause a cessation of vegetative growth in leaf and root of both wheat cultivars. Genes for oxidative stress and detoxification of ROS were not significantly regulated after all B conditions. This result was in accordance with the measurements of antioxidant enzyme activities. Genes related protein degradation were induced more under all B conditions in Atay than Bolal. These results considering programmed cell death in senescing leaves were confirmed by the visual phenotype of the plants. Our findings may introduce new targets for breeding researches aimed at improving B tolerance of crop plants.