Grape response to salinity stress and role of iron nanoparticle and potassium silicate to mitigate salt induced damage under in vitro conditions

Abstract

Grape softwood cuttings of Khoshnaw cultivar were cultured using tissue-culture methods to study the effect of iron nanoparticles and potassium silicate under salinity conditions during the 2015-2016 growing season. The treatments consisted of salinity stress (0, 50, and 100 mM NaCl), nanoparticles of iron (0, 0.08, and 0.8 ppm), and potassium silicate (0, 1, 2 mM). The results also showed that the application of iron nanoparticles and potassium silicate significantly increased the total protein content and reduced proline, enzymatic antioxidant activity and hydrogen peroxide. Salinity stress reduced membrane stability index while increased malondialdehyde content. Increase of membrane stability index and reduction of malondialdehyde content were obtained for 2 mM potassium silicate and 0.8 ppm iron nanoparticle. Iron and potassium silicate were shown to lower the sodium content and increase the potassium content under salinity-stress conditions. The highest ratio of sodium to potassium was observed in plants under salinity conditions (100 mM) treated with neither iron nanoparticles nor potassium silicate; conversely, the lowest ratio was achieved in plants treated with both 0.8 ppm iron nanoparticles with 1 mM and 2 mM potassium silicate under non-stress conditions. These results indicate that the application of micronutrients in stressful conditions is a suitable method to compensate for the negative effects of salinity stress. Tissue culture in this study was shown to be an economically efficient and applicable technique for producing grape softwood cuttings to be used in experiments.

Putrescine-functionalized carbon quantum dot nanoparticles (Put-CQD) effectively prime grape (Vitis vinifera cv. Sultana) against salt stress

“…Iron-NPs were also shown to enhance proline content of grapevine under control and salinity conditions [31]. This enhancement was reported following QD application, as well [45], in accordance with the current study.…”

“…Put acts as a signaling regulator responsible for inward recti cation of rectifying K + channels [28]. Mozafari et al [31] reported positive effect of iron-NPs on decreasing Na + and increasing K + contents in plants under salinity conditions. To our knowledge, no previous report existed showing the effect of carbon-based NPs on Na + and K + contents in plants under salt stress conditions.…”

“…In general, salinity enhances Na + and reduces K + ions in plants due to excessive amounts of Na + in soil or nutrient solution that imbalance ion uptake by plants [27,28,31]. Bene cial effect of Put or other PAs on reducing Na + and increasing K + contents in plants under salinity was reported [23,26].…”

“…Proline is an osmolyte, metal chelating, antioxidant and signaling molecule [50]. Proline accumulates under abiotic stresses due to its role as osmotic regulator and ROS detoxi er that preserves membrane integrity, subcellular structures, antioxidant enzymatic activities and protein structure [31,50]. Increase in proline content in salt-stressed grapevine has been previously recorded [31], likely due to a decrease in proline oxidation and increase in its biosynthesis [51].…”

“…Grapevine (Vitis vinifera L.) is considered as one of the most important and high-value agricultural products cultivated worldwide, consequently with signi cant economic importance [31]. Grapevine, relatively sensitive to salt stress, suffers signi cant losses in growth and productivity and also fruit quality under salinity conditions [32].…”