The photomorphogenetic reaction of pea plants (Pisum sativum L.) on ultraviolet irradiation effect

Abstract

Aim. The comparation of photomorphogenetic response of pea plants in wide dose range of UV-C and UV-B irradiation was studied. Methods. Pea plants (Pisum sativum L.) cultivar Aronis were grown in water culture during 10 days and then were irradiated by UV-B and UV-C irradiation in doses 1, 2, 4, 8 and 15 kJ/m2. The length of shoots and roots and fresh weight of pea plants were measured. Results. It is established that UV-C irradiation caused strong inhibition effect on shoot growth against UV-B in the same doses. It is shown that the dose of 8 kJ/m2 was the threshold of the UV-B and UV-C effect. Dose above 8 kJ/m2 caused growth inhibition. The dose of 2 kJ/m2 caused the hormesis effect. Stem growth inhibition under the UV-C stimulated root growth. Conclusions. Comparative study of UV-B and UV-C irradiation demonstrated that the hormesis effect on plant growth was shown in the same dose of 2 kJ/m2. The inhibition effect of UV-C irradiation was stronger than UV-B in the same doses. Keywords: UV-B, UV-C, Pisum sativum L., hormesis.