Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9485697 | Environmental and Experimental Botany | 2005 | 10 Pages |
Abstract
From the leaves of barley seedlings (Hordeum vulgare L. cv. Alfa) UV-B induced compounds, with maximum absorbance at 438Â nm (A438) were extracted. The relationship between the level of UV-B induced compounds and UV-B tolerance of barley seedlings was investigated. The level of these compounds depended on the time of UV-B irradiation. They increased 4Â h after UV-B treatment, reached maximum after 24Â h and then declined. Contrary, the syntheses of UV-absorbing compounds extracted in acidified methanol continued for a long period after UV exposure and after 120Â h the values of A300 are higher. The content of UV-induced compounds enhanced in the plants treated with proline before UV-B irradiation and decreased as a result of NaCl pretreatment in a concentration depending manner. A physiological response to UV-B irradiation was evaluated by measuring the oxygen evolution rate, chlorophyll fluorescence and chlorophyll/carotenoids ratio. No correlation was found between the level of A438 and UV-B tolerance of barley seedlings. It is possible these compounds to play a subtle role in plant UV-B protection than simple UV-B screening or to serve as stress markers.
Keywords
Related Topics
Life Sciences
Agricultural and Biological Sciences
Ecology, Evolution, Behavior and Systematics
Authors
Ivanka Fedina, Maya Velitchkova, Katya Georgieva, Irena Grigorova,