Effects of Exogenous Linoleic Acid on Barley (Hordeum vulgare L.) Seedlings Under Salinity

Uçarlı C.

Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi, vol.12, no.3, pp.1790-1800, 2022 (Peer-Reviewed Journal)


Salt stress adversely affects plants and causes different levels of morphological,
physiological, biochemical, and molecular changes at different growth stages. Polyunsaturated fatty
acids (PUFAs), such as linoleic acid, are main components of membrane lipids and determine the
fluidity and stability of the cell membrane. In addition, PUFAs have a crucial role in maintaining the
structure and function of the cell membrane which is damaged by salinity. There may be a relationship
between level of PUFAs in membrane lipids and salinity tolerance. The present study was carried out
to examine the effects of exogenous application of 0.5 mM linoleic acid (LA) on barley seedlings
Hordeum vulgare L. cv. Martı) grown in hydroponic conditions under 160 mM NaCl. The treatment
with LA ameliorated the stress generated by NaCl by increasing osmolyte level and decreasing ion
leakage percentage and H
2O2 content within hours. Besides, LA significantly enhanced expression of
salt-responsive transcription factor
HvDRF2 and ROS scavenger gene HvMT2 as 105- and 40-fold,
respectively, in the leaves of barley seedlings under salinity conditions. While LA slightly increased
the gene expression of ascorbate peroxidase (HvAPX), glutathione S-transferase (
HvGST6) and copper
zinc superoxide dismutase (
HvCu/ZnSOD) in the roots of barley seedlings, the expression of these
genes was not changed in the leaves under salinity compared to salt-stressed samples. This study
provides novel insights for effects of LA on improvement of salinity tolerance in barley.