Expression of genes related to Na⁺exclusion and proline accumulation in tolerant and susceptible wheat genotypes under salt stress

Abstract

In the present investigation, expression of genes related to Na + exclusion such as salt overly sensitive (TaSOS1) and Na + /H + antiporter (TaNHX1) and proline accumulation such as pyrroline-5-carboxylate reductase (P5CR) and glutamate synthase (GOGAT) was studied in seedlings of Kharchia 65 (Kh 65, salt tolerant) and HD 2009 (sensitive) under salt stress (ECe, 12 dSm -1 ) and controlled conditions. As compared to HD 2009, Kh 65 showed significantly lower accumulation of Na + (p < 0.01) and higher accumulation of proline (p < 0.05) in leaf blade under salt stress. The relative expression of TaSOS1 increased significantly (p < 0.001) in roots of Kh 65 (4.31-fold) while it decreased in HD 2009. There was significantly higher (p < 0.01) relative expression of TaNHX1 (27.57-fold) in leaf and 3.07-fold in roots of Kh 65 as compared to 3.65-and 0.87-fold increase in leaf and roots of HD 2009, respectively, under salt stress. There was significantly (p < 0.05) higher accumulation of proline as compared to HD 2009 in leaf tissues. There was significantly higher (p < 0.01) expression of P5CR (5.23-fold in leaf and 8.77-fold in the root) and glutamate synthase (6.0-fold in roots) in Kh 65 as compared to HD 2009. The study demonstrated that upregulation of genes for Na + exclusion in root and compartmentation in leaf and increased proline concentration are associated with tolerance to salinity stress in wheat. The information will be useful for improving wheat genotypes for salt tolerance.

Expression of Arabidopsis Ornithine Aminotransferase (AtOAT) encoded gene enhances multiple abiotic stress tolerances in wheat

“…Glutamate pathway of proline biosynthesis is predominantly active during abiotic stress conditions. An increased expression of P5CS under osmotic stress was reported in wheat, barley (Hordeum vulgare L.), tomato (Solanum lycopersicum L.), switchgrass (Panicum virgatum), and Lepidium draba (Rana et al 2016;Bandurska et al 2017;Guan et al 2019;Lopez-Galiano et al 2019;Goharrizi et al 2020). Our present study also reveals the activation of glutamate pathway in wheat under drought, salt and heat stresses as an increased expression of TaP5CS1 and TaP5CR was observed in AtOAT expressed transgenic plants.…”

Agronomical, physiological and molecular evaluation reveals superior salt-tolerance in bread wheat through salt-induced priming approach

“…Kh65 (salt-tolerant), while it was about a 4-fold increase in Cv. HD2009 (sensitive) (Rana et al, 2016).…”

Different proline responses of two Algerian durum wheat cultivars to in vitro salt stress

“…membrane, alter levels of growth regulators, inhibit enzymes, disrupt photosynthesis, 66 interfere with ionic homeostasis, produce harmful reactive oxygen species (ROS), and thus 67 lead to plant death (Munns and Tester, 2008;Julkowska and Testerink, 2015). High Na + 68 concentrations also have inhibitory effects on the absorption of major nutrients with similar 69 physicochemical properties, such as K + , by the root (Almeida et The deleterious consequences of salt stress on the plant can in some cases be counteracted 90 by the accumulation of solute compounds, such as the amino acid proline (Zhang et al,91 2016; Rana et al, 2016, Annunziata et al, 2017. The accumulation of proline in plants 92 growing under saline conditions may contribute to stress protection through a number of 93 mechanisms, for example, as an osmotic agent, as a ROS quencher, as a stabilizer of 94 membranes and macromolecules, or as an inducer of the expression of salt-stress responsive 95 genes (Hayat et al, 2012).…”