Effect of GABA on seed germination and seedling growth of rapeseed under salt stress

Abstract In order to evaluate the impacts of gamma-aminobutyric acid (GABA) priming on rapeseed germination and seedling growth under salt stress, we conducted pot experiments using salt-sensitive rapeseed variety 'Zhongshuang 11'. To study the influence of seed priming on the morph-physiological traits, rapeseed plants were treated with 150 mm NaCl after priming of GABA (0.5, 1, 1.5, 2.0, 2.5 mM). Data on morphological traits, oxidation damage and antioxidant system were contrasted before. Our findings revealed that NaCl significantly reduced root activity, chlorophyll content and antioxidative enzymes activities, and also hindered germination, seedlings and morphological growth traits of rapeseed plants. However, priming of GABA (1.5 mM) treatment to salt-stressed plants not only increased the germination and vigor indexes but also significantly improved root length and height of rapeseed. Moreover, compared to CK2, GABA (1.5 mM) application significantly enhanced root activity and chlorophyll content of 77.02% and 38.06%, respectively. GABA (1.5 mM) reduced the H2O2 and MDA content. Furthermore, Compared to CK2, GABA (1.5 mM) significantly enhanced the antioxidant enzymes i.e SOD, POD, CAT and APX activities of 34.81%, 239.46%, 66.20%, and 57.84%, as well as increased AsA and GSH content of 89.77% and 8.90%, respectively. These findings elucidated that GABA (1.5 mM) priming not only increased the germination rate, seedlings growth and antioxidants traits but also successfully alleviate the adverse impacts of salinity stress.