Presoaking with hemin improves salinity tolerance during wheat seed germination

Abstract

The aim of this study was to investigate whether presoaking with hemin, an inducer of heme oxygenase-1 (HO-1), could alleviate salinity damage during wheat seed germination in comparison with the pretreatment of a well-known nitric oxide (NO) donor sodium nitroprusside (SNP). The results showed that, compared with the samples upon 150 mM NaCl salt stress alone, both 10 lM hemin and 200 lM SNP pretreatments could (1) significantly attenuate the inhibition of seed germination and thereafter seedling growth; (2) induce HO expression; (3) enhance amylase activity, thus accelerating the formation of reducing sugar and total soluble sugar; and (4) increase the potassium (K) to sodium (Na) ratio, particularly in the shoot parts. Hemin and SNP could also increase antioxidant enzyme activities, including superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POD), and ascorbate peroxidase (APX), thus resulting in the alleviation of oxidative damage, as indicated by the decrease of thiobarbituric acid reactive substances (TBARS) content.Moreover, semi-quantitative RT-PCR and isozymatic analysis illustrated that hemin and SNP pretreatment were able to up-regulate the expression of Mn-SOD (especially) and Cu/Zn-SOD gene, and activate SOD isozymatic activities. Since the addition of the NO scavenger methylene blue (MB) differentially reversed the above effects, the protective roles of hemin might be related to the induction of endogenous NO signal. Meanwhile, hemindriven NO production was confirmed. Together, these results indicated that hemin exerted an advantageous effect on enhancing salinity tolerance during wheat seed germination, which might interact with NO.

Effect of Chemical Synthesis Silver Nanoparticles on Germination Indices and Seedlings Growth in Seven Varieties of Lycopersicon esculentum Mill (tomato) Plants

“…Exposure of tomato seeds to carbon nanotubes (CNTs) resulted in enhance seed germination and growth rate due to support water uptake inside seeds [25]. Also reported that AgNPs and osmopriming stimulate seed germination by enhanced supply of soluble carbohydrates to the growing embryo, which was caused by an increase in amylase activities [26]. Exposure to AgNPs significantly decreased GP in Super stone and Super strain B varieties at 75 and 100 mg l -1 concentrations.…”

Nitric oxide is involved in hemin-induced cucumber adventitious rooting process

“…Previous studies showed that the concentrations and the time points of treatments with these inhibitors or scavengers were suitable for investigating the role of HO/CO or NO in the root developmental signaling (Pagnussat et al, 2002(Pagnussat et al, , 2003(Pagnussat et al, , 2004Xuan et al, 2007Xuan et al, , 2008de Montaigu et al, 2010;Xu et al, 2011). Finally, excised cucumber hypocotyls (5-mm-long segments of the hypocotyl base, where adventitious root develops; Lanteri et al, 2008) were used for the following determination.…”

“…NO content determination by using Griess reagent assay NO content from excised cucumber hypocotyls was determined using the previous method (Ding et al, 1988;Xu et al, 2005;Zhou et al, 2005;Xu et al, 2011) with some modifications. Samples were ground in a mortar and pestle in 3 ml of 50 mM cool acetic acid buffer (pH 3.6, containing 4% zinc diacetate).…”

The role of nitric oxide in priming-induced low-temperature tolerance in two genotypes of tomato

“…On the other hand, suboptimal temperatures increased the NO content of the controls. Enhancement of endogenous NO content has been reported for plants under cold (Zhao et al, 2009), heat (Song et al, 2006) and salinity (Xu et al, 2011) stresses. NO acts as an important signal in responses against abiotic stress.…”

“…Both treatments enhanced amylase activities and seeds contained more soluble sugars, being able to more readily support metabolic activities and consequently resulting in a higher rate of emergence, which correlated with a-amylase activity and GI. Enhancement of amylase activity and sugar content by SNP (Zhang et al, 2005;Xu et al, 2011) and priming (Farooq et al, 2006) Nitric oxide in tomato seed priming 127 determining lateral root development, allowing further understanding of the components that control plant cell differentiation and proliferation. Therefore, the NOinduced increase in seedling growth under suboptimal temperature conditions may have been due to an increase in cell division and/or cell enlargement, although these phenomena were not examined in the present study.…”