7 research outputs found
Contribution of Glutathione and Ascorbate to Realization of the Protective Effect of Nitric Oxide on Wheat Plants under Drought
Nitric oxide (NO) is an important signaling molecule capable of increasing plant resistance to different environmental stresses. However, the mechanisms underlying the protective effect of NO on the plants remains poorly understood. In the present study, we have investigated the effect of 200 μmol SNP (Sodium Nitroprusside) on the growth and ascorbate acid (AsA) and glutathione (GSH) metabolism in wheat plants (Triticum aestivum L.) under the influence of 12% PEG. The results showed that the application of SNP to wheat plants increased AsA and GSH contents and enhancement of glutathione reductase activities. Meanwhile, growth stabilization and a decrease in the damaging effect of drought on the state of membrane structures were noted in plants, as judged by the level of MDA in them. Our results suggested that SNP can regulate the ascorbate and glutathione metabolism and has important roles in alleviating oxidative damage and enhancing drought tolerance in wheat
Involvement of Nitric Oxide in Methyl Jasmonate-Mediated Regulation of Water Metabolism in Wheat Plants under Drought Stress
Drought is a serious challenge that causes significant crop loss worldwide. The developmental processes of plants are regulated by phytohormones and signaling molecules that crosstalk together in signaling cascades. We suppose that nitric oxide (NO) is a secondary messenger of the JAs signaling pathway, as 10−7 M methyl jasmonate (MeJA) pretreatment regulates NO accumulation in wheat plants under drought stress, modulated by 12% polyethylene glycol (PEG), and in control plants. This study aimed to compare 2 × 10−4 M nitric oxide donor sodium nitroprusside (SNP) and MeJA pretreatments in regulating growth and water balance parameters at the vulnerable initial first-leaf stage of wheat growth. The application of 12% PEG decreased transpiration intensity twofold, relative water content (RWC) by 7–9%, and osmotic potential of cell sap by 33–40% compared with those of control plants. Under drought, MeJA- and SNP-pretreated plants decreased transpiration intensity by 20–25%, RWC by 3–4%, and osmotic potential of cell sap by 16–21% compared with those of control plants, and enhanced the proline content by 25–55% compared with MeJA- and SNP-untreated plants. Our results suggest that pretreatment with MeJA as well as SNP could mitigate drought stress in wheat plants. Similarities in MeJA- and SNP-induced shifts in plant water balance suggested that NO is a mediator of MeJA-induced regulation of wheat water content during water deficit
Endogenous cytokinins mediate growth-stimulating and protective action of the HUMI preparation on wheat plants inoculated with Tilletia caries
Wheat germ agglutinin is involved in the protective action of 24-epibrassinolide on the roots of wheat seedlings under drought conditions
Methyl jasmonate alleviates water stress-induced damages by promoting dehydrins accumulation in wheat plants
Cytokinin Stimulates Chloroplast Transcription in Detached Barley Leaves1[OA]
Chloroplasts are among the main targets of cytokinin action in the plant cell. We report here on the activation of transcription by cytokinin as detected by run-on assays with chloroplasts isolated from apical parts of first leaves detached from 9-d-old barley (Hordeum vulgare) seedlings and incubated for 3 h on a 2.2 × 10−5 m solution of benzyladenine (BA). Northern-blot analysis also detected a BA-induced increase in the accumulation of chloroplast mRNAs. A prerequisite for BA activation of chloroplast transcription was preincubation of leaves for 24 h on water in the light, resulting in a decreased chloroplast transcription and a drastic accumulation of abscisic acid. Cytokinin enhanced the transcription of several chloroplast genes above the initial level measured before BA treatment, and in the case of rrn16 and petD even before preincubation. Cytokinin effects on basal (youngest), middle, and apical (oldest) segments of primary leaves detached from plants of different ages revealed an age dependence of chloroplast gene response to BA. BA-induced stimulation of transcription of rrn16, rrn23, rps4, rps16, rbcL, atpB, and ndhC required light during the period of preincubation and was further enhanced by light during the incubation on BA, whereas activation of transcription of trnEY, rps14, rpl16, matK, petD, and petLG depended on light during both periods. Our data reveal positive and differential effects of cytokinin on the transcription of chloroplast genes that were dependent on light and on the age (developmental stage) of cells and leaves