Salinity effects on photosynthetic pigments, proline, biomass and nitric oxide in Salvinia auriculata Aubl.

Abstract

Cite as: Gomes, M.A.C. et al. Salinity effects on photosynthetic pigments, proline, biomass and nitric oxide in Salvinia auriculata Aubl. Acta Limnologica Brasiliensia, 2017, vol. 29, e9. Abstract: Aims: Effects of salt stress on the physiology of Salvinia auriculata were investigated. Method: Plants were supplemented with 0, 50, 100 and 150 mmol L -1 NaCl and incubated for 5 days. NO content was evaluated after 2 hours and 5 days. Photosynthetic pigments, proline and nutrients were analyzed after 5 days. Major Results: Higher chlorophyll a content was observed in plants treated with 50 mmol L -1 , decreasing in higher NaCl concentrations, while chorophyll b content decreased with increasing NaCl concentrations. Exposure to 50 mmol L -1 NaCl increased biomass, while higher concentrations caused loss of biomass. Ca, K and Mg decreased with increasing NaCl concentrations, and the Na/K ratio was significantly increased at 150 mmol L -1 NaCl. Proline increased significantly at 150 mmol L -1 . Extracellular NO content increased after 2 hours, with significantly higher NO concentrations in roots observed at 50 mmol L -1 . Decreases in NO content were observed after 5 days. Conclusions: The results indicate that moderate salinity induces NO production earlier during incubation, probably associated to signaling for the production of compounds that assist in stress tolerance. At higher concentrations, this tolerance is reduced. This allows for further understanding of the physiological and biochemical mechanisms associated with the adaptation of this macrophyte to saline conditions, which, in turn, affect this species ecology and distribution in coastal areas.Keywords: Salvinia auriculata; salinity stress; nitric oxide; clorophyll; NaCl; macrophyte.Resumo: Objetivos: Efeitos do estresse salino sobre a fisiologia de Salvinia auriculata foram investigados. Metodologia: As plantas foram expostas a 0, 50, 100 e 150 mmol de NaCl L -1 e incubadas durante 5 dias. O conteúdo de NO foi avaliado após 2 horas e 5 dias. Pigmentos fotossintéticos, prolina e nutrientes foram analisados após 5 dias. Resultados Principais: Observou-se maior teor de clorofila a em plantas tratadas com 50 mmol L -1

Effect of Exopolysaccharide-Producing Bacteria and Melatonin on Faba Bean Production in Saline and Non-Saline Soil

“…Under stress conditions, the availability of nutrients in the soil is reduced due to a decreased solubility, which leads to decreased absorption and concentrations in plants [54]. The results observed in the present study for nutrient concentrations are parallel to the results obtained by Gomes et al [55], who reported that the Na + , Cl − , and Na/K ratios increased, while Ca 2+ , K + , and Mg 2+ reduced with an increasing salinity; N and P showed no significant differences among saline treatments. Castanares and Bouzo [14] reported that the K concentration decreased and the Na + /K + ratio increased under salinity stress.…”

Influence of exogenously applied nitric oxide on strawberry (Fragaria × ananassa) plants grown under iron deficiency and/or saline stress

“…In the present study, stress conditions decreased the NO contents of strawberry plants. Likewise, in Salvinia auriculata, Gomes et al () showed that exposure to high salinity regimes increased extracellular NO level after 2 h, while it decreased when tested after 5 days of salinity stress. Contrarily, in tomato, Manai et al () reported that exogenous application of SNP enhanced salinity stress tolerance which was ascribed to NO‐induced activation of antioxidant enzymes.…”

“…For example, in different studies, salt-induced enhanced root to shoot ratio has been observed, e.g. in Euonymus japonica (Gómez-Bellot et al 2013), Callistemon citrinus (Álvarez and Sánchez-Blanco 2014) and Myrtus cummunis (Acosta-Motos et al 2015). Astolfi et al (2006) and Zhang et al (2012) have reported that ID stress also enhanced the root to shoot ratio in barley and peanut plants, respectively.…”

“…Photosynthetic activity of most plants decreases under saline conditions because PSII activity is disturbed and thylakoid membrane along with its pigments is damaged due to formation of ROS under salinity stress (Dombrowski , Naeem et al , Shaheen et al , Wu et al , Deinlein et al , AbdElgawad et al , Askary et al , Gomes et al ). Like many other stresses, the deficiency of iron can also generate ROS and disturb the electron transport chain in the chloroplast because iron plays an important role in it (Graziano and Lamattina ).…”

“…Different letters (a-g) on bars show significant difference among means within each parameter. (Dombrowski 2003, Naeem et al 2010, Shaheen et al 2012, Wu et al 2012, Deinlein et al 2014, AbdElgawad et al 2016, Askary et al 2017, Gomes et al 2017. Like many other stresses, the deficiency of iron can also generate ROS and disturb the electron transport chain in the chloroplast because iron plays an important role in it (Graziano and Lamattina 2005).…”