Evidence towards the involvement of nitric oxide in drought tolerance of sugarcane

Abstract

Exogenous supply of nitric oxide (NO) increases drought tolerance in sugarcane plants. However, little is known about the role of NO produced by plants under water deficit. The aim of this study was to test the hypothesis that drought-tolerance in sugarcane is associated with NO production and metabolism, with the more drought-tolerant genotype presenting higher NO accumulation in plant tissues. The sugarcane genotypes IACSP95-5000 (drought-tolerant) and IACSP97-7065 (drought-sensitive) were submitted to water deficit by adding polyethylene glycol (PEG-8000) in nutrient solution to reduce the osmotic potential to -0.4 MPa. To evaluate short-time responses to water deficit, leaf and root samples were taken after 24 h under water deficit. The drought-tolerant genotype presented higher root extracellular NO content, which was accompanied by higher root nitrate reductase (NR) activity as compared to the drought-sensitive genotype under water deficit. In addition, the drought-tolerant genotype had higher leaf intracellular NO content than the drought-sensitive one. IACSP95-5000 exhibited decreases in root S-nitrosoglutathione reductase (GSNOR) activity under water deficit, suggesting that S-nitrosoglutathione (GSNO) is less degraded and that the drought-tolerant genotype has a higher natural reservoir of NO than the drought-sensitive one. Those differences in intracellular and extracellular NO contents and enzymatic activities were associated with higher leaf hydration in the drought-tolerant genotype as compared to the sensitive one under water deficit.

Label‐Free Quantitative Proteomics of Enriched Nuclei from Sugarcane (Saccharum ssp) Stems in Response to Drought Stress

“…In this work, a commercial genotype of sugarcane from São Paulo State, in Brazil, was used to study the proteome of drought‐stressed sugarcane. Previous studies showed that the genotype used here had a higher capacity to accumulate biomass compared with other commercial varieties when exposed to drought …”

“…In the present study, we used a highly productive commercial sugarcane cultivar (IACSP 95–5000), which has been characterized as drought‐tolerant with the aim to identify drought‐stress responsive proteins in the stems which are the major sinks of photosynthates used to produce the main products from sugarcane (ethanol, biomass, and sugar). These proteins are responsible for the control of metabolic pathways that affect directly the quality and yield of sugarcane.…”

How Nitric Oxide Down-Regulates Cryptochrome 1 from Canola in Blue but Not Red Light, and Reduces Hypocotyl Dwarfism in Lead and Drought Stress

“…Decreased NO levels prevent stomatal closure caused by SNP [34], so adding NO and its interaction can increase drought tolerance. Furthermore, [35] recently reported that the exogenous supply of NO enhances drought tolerance in sugarcane plants.…”

Involvement of Calcium and Calmodulin in Nitric Oxide-Regulated Senescence of Cut Lily Flowers

“…The possibility that NO and Ca 2+ , as plant signaling regulators, may work together in response to abiotic stresses has been reported ( Silveira et al, 2017 ). In the present study, when Ca 2+ chelators, Ca 2+ channel inhibitors, and CaM antagonists were applied, the promoting effects of NO on vase life was blocked.…”