The influence of selective light on the growth reaction and antioxidant system of seedlings Pisum sativum L.

Aim. Study of the effect of red (660 nm), green (530 nm) and blue (450 nm) light on the growth processes and the state of the antioxidant system in the axial organs of seedlings of pea plants. Methods. Etiolated seedlings of pea Maecenat variety were irradiated with selective light with different spectrum of RL (660 nm), GL (530 nm), BL (450 nm) to activate photoreceptor systems of plants. In 10-day-old seedlings, growth response was determined – linear growth and biomass accumulation, as well as indicators of antioxidant system – hydrogen peroxide content and activity of oxidases – catalase and nonspecific peroxidase in axial organs of seedlings: in the aboveground part and roots. Results. Irradiation of the RL and the GL stimulates the accumulation of seedling biomass in the aboveground part and roots. BL inhibits the growth response of seedlings. The maximum stimulating effect is shown by the GL. The state of the antioxidant system in etiolated seedlings is characterized by organ specificity. Under the action of selective light, the content of the main form of ROS – hydrogen peroxide and shoots and in the roots, significantly stimulates the activity of catalase and peroxidase enzymes in the aboveground part of the seedling and is inhibited in the roots. The maximum effect in the aboveground part is shown by the GL, in the roots of the RL and the BL. Conclusions. The established effects of selective light irradiation are manifested differently in the aboveground and underground parts of seedlings. Possible mechanisms of connection of a condition of antioxidant system with separate aspects of signaling in photomorphogenesis of plants are discussed. Keywords: Pisum sativum L., selective light, RL (660 nm), GL (530 nm), BL (450 nm), growth reaction, axial organs, H2O2, catalase, peroxidase.