Biomics

Plants growing in hypoxic conditions need to adapt to oxygen deficiency in substrate, including with the formation of lysigenous aerenchyma formation. Although lysigenous aerenchyma formation is well understood, its creation on different plant age is not well studied. In current article is described aerenchyma formation in roots of barley growing in hydroponic conditions up to 30 day after germination (DAG). It is shown that aerenchyma in primary roots developed on 7 DAG, and its volume in root cortex significantly enlarged, especially in basal root part, up to 30 DAG. H2O2 content increased from basal to apical part of roots and rose in 3-4 times on 30 DAG in all root parts. Guaiacol peroxidase (GP) demonstrated high activity on 27-30 DAG, and it coincided with aerenchymal lacunae origin. Superoxide dismutase activated earlier than GP and its activity may be involved in initial stage of aerenchyma formation. A clear correlation between H2O2 and antioxidative enzymes was not found, probably due to activation of the other processes of synthesis and degradation of H2O2.

roots, aerenchymal lacunae, barley, peroxidase, lack of oxygen, hydroponics

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