A POSSIBLE ROLE OF SOME ANTIOXIDATIVE ENZYMES IN TOLERANCE OF PAULOWNIA TO NaCl

T. Georgieva, K. Ivanova, Y. Markovska, K. Miladinova

Abstract: The effect of salt stress on activities of glutathione reductase (GR), ascorbate peroxidase (APX), catalase (CAT), guaiacol peroxidase (GPOX), total glutathione, ascorbate and H2O2 in three Paulownia lines (P. elongata x fortunei x elongata – T2, P. elongata x elongata – T4, P. elongata x kawakarnii – EK) grew as hydroponic culture at three levels of salinity, 50 mmol.l–1, 100 mmol.l–1, 200 mmol.l–1 sodium chloride (NaCl) solution was investigated. The magnitude of reduction of root, stem, leaf dry biomass and ratio total leaf area/ total dry biomass (LAR) were more pronounced in T4 than in T2 and EK after treatment.
NaCl led to increase the leaf levels of H2O2, glutathione and ascorbate in T4 and T2, but not in EK. Salinity signifi cantly inhibited the activities of CAT, GPOX and APX in T4. Increases in the enzyme activities by NaCl namely in T2 suggested that they might be playing a possible role in tolerance of this line to salinity. Our results suggested that T2 line was more tolerant to salt stress than EK and T4 lines. We were looking for suitable physiological and biochemical criterions in order to develop practicable strategy for selecting salt tolerant lines of Paulownia, which were produced by BioTree Ltd., Bulgaria.

Keywords: antioxidants; hydroponic; Paulownia; protective enzymes; salinity

Date published: 2017-10-19