S‐nitrosoglutathione spraying improves stomatal conductance, Rubisco activity and antioxidant defense in both leaves and roots of sugarcane plants under water deficit

• Published in: Physiologia plantarum Vol. 160; no. 4; pp. 383 - 395
• Main Authors: Silveira, Neidiquele M., Marcos, Fernanda C. C., Frungillo, Lucas, Moura, Bárbara B., Seabra, Amedea B., Salgado, Ione, Machado, Eduardo C., Hancock, John T., Ribeiro, Rafael V.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2017; Wiley Subscription Services, Inc
• Subjects: Antioxidants; Antioxidants - metabolism; Assimilation; Biochemistry; Carbon dioxide; Catalase; Catalase - metabolism; Conductance; Crop production; Crops; Damage prevention; Dehydration; Enzymes; Leaves; Nitric oxide; Nitric Oxide Donors - pharmacology; Organs; Oxidation-Reduction; Oxygenase; Phosphoenolpyruvate carboxylase; Phosphoenolpyruvate Carboxylase - drug effects; Phosphoenolpyruvate Carboxylase - metabolism; Photosynthesis; Photosynthesis - drug effects; Plant growth; Plant Leaves - drug effects; Plant Leaves - enzymology; Plant Leaves - physiology; Plant Roots - drug effects; Plant Roots - enzymology; Plant Roots - physiology; Plant Stomata - drug effects; Plant Stomata - enzymology; Plant Stomata - physiology; Plant Transpiration - drug effects; Plants; Plants (botany); Polyethylene glycol; Polyethylenes; Resistance; Ribulose-1,5-bisphosphate; Ribulose-bisphosphate carboxylase; Ribulose-Bisphosphate Carboxylase - drug effects; Ribulose-Bisphosphate Carboxylase - metabolism; Roots; S-Nitrosoglutathione - pharmacology; Saccharum - drug effects; Saccharum - enzymology; Saccharum - physiology; Spraying; Stomata; Stomatal conductance; Sugarcane; Superoxide dismutase; Superoxide Dismutase - metabolism; Water - physiology; Water deficit
• ISSN: 0031-9317; 1399-3054
• DOI: 10.1111/ppl.12575

Water deficit is a major environmental constraint on crop productivity and performance and nitric oxide (NO) is an important signaling molecule associated with many biochemical and physiological processes in plants under stressful conditions. This study aims to test the hypothesis that leaf spraying of S‐nitrosoglutathione (GSNO), an NO donor, improves the antioxidant defense in both roots and leaves of sugarcane plants under water deficit, with positive consequences for photosynthesis. In addition, the roles of key photosynthetic enzymes ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC) in maintaining CO2 assimilation of GSNO‐sprayed plants under water deficit were evaluated. Sugarcane plants were sprayed with water or GSNO 100 μM and subjected to water deficit, by adding polyethylene glycol (PEG‐8000) to the nutrient solution. Sugarcane plants supplied with GSNO presented increases in the activity of antioxidant enzymes such as superoxide dismutase in leaves and catalase in roots, indicating higher antioxidant capacity under water deficit. Such adjustments induced by GSNO were sufficient to prevent oxidative damage in both organs and were associated with better leaf water status. As a consequence, GSNO spraying alleviated the negative impact of water deficit on stomatal conductance and photosynthetic rates, with plants also showing increases in Rubisco activity under water deficit.