Effect of gamma radiation on the content of free proline and malonic aldehyde in barley seedlings

It is well known that the formation of reactive oxygen species in the organism due to the impact of negative factors of various nature is one of the main mechanisms of stress state formation at the level of cells and tissues. In plants reactive oxygen species play a key role in the response to abiotic stress through signalling and activation of the defence system. The purpose of the work is to study the effect of gamma radiation on the content of malondialdehyde (MDA) and free proline in seedlings of common barley (Hordeum vulgare L.) of three varieties. The effect of radiation was assessed by changes in the concentrations of the substances under study, which was determined by the photometric method. It was shown that a statistically significant increase in the MDA content in germinated seeds of the Vityaz and Ladny varieties was observed when irradiated at doses of 2, 5, 10, 25 and 50 Gy, and in the Badjoriy variety when irradiated at doses of 2, 20, 25 and 50 Gy. An increase in the concentration of free proline was observed at all studied doses of gamma irradiation, with the exception of irradiation at a dose of 15 Gy for the Vityaz and Ladny varieties. A relationship was noted between the content of free proline and MDA in plant material (correlation coefficient for the Vityaz variety - 0.871±0.121; for the Ladny variety - 0.892±0.103; for the Badjoriy variety - 0.886±0.112). Regardless of the variety, the observed changes in the studied parameters demonstrate similar dynamics, which is of practical value for assessing the degree of technogenic pollution of agricultural biogeocenoses. The obtained quantitative data will make it possible to determine the optimal radiation doses for each zoned variety, which will help optimize the use of radiation technologies in agriculture.