1 Institute of Botany, ANAS
2 Institute of Genetic Resourses, ANAS
Drought is one of the major factors limiting the yield and quality of crops worldwide. Barley characterized
by high genetic diversity constitutes a valuable source for assessment of the responses of contrast genotypes
to environmental constraints. Antioxidative metabolism plays an important role in plant responses to
drought. The main aim of the study was to define variations in drought-tolerance of barley genotypes based
on the obtained differencies in the levels of antioxidant enzymes during the drought stress. The activities and
isoform profiles of catalase (CАТ), ascorbate peroxidase (APX), glutathione reductase (GR), and superoxide
dismutase (SOD) were analyzed in four barley genotypes grown under soil drought. Drought stress
caused an increase in the activities of CАТ and SOD in all studied genotypes, while APX activity decreased.
The total GR activity increased substantially in genotypes K 2778 and St.Garabag 7 and decreased in №77
local and St.Pallidum 596 genotypes under severe water stress. No detectable differences were observed in
the isoenzyme composition (appearance or loss of new isoenzymes) of plants subjected to soil drought in
contrast to control ones. However, the bands of corresponding isoforms in electrophoretic spectra were intensified
in stressed barley leaves.