Hydrogen peroxide acts as a signal molecule in CO2 laser pretreatment-induced osmotic tolerance in wheat seedling
Z.B. Qiu, Q. Li, Z.Z. Bi, M. Yuehttps://doi.org/10.17221/271/2010-PSECitation:Qiu Z.B., Li Q., Bi Z.Z., Yue M. (2011): Hydrogen peroxide acts as a signal molecule in CO2 laser pretreatment-induced osmotic tolerance in wheat seedling. Plant Soil Environ., 57: 403-408.
The objective of this study was to test whether hydrogen peroxide (H2O2) is involved in laser pretreatment-induced water tolerance in wheat seedlings due to its nature as a second messenger in stress responses. The results showed that 3 min laser pretreatment could enhance water tolerance in wheat seedlings by decreasing the concentration of malondialdehyde (MDA), the production rate of superoxide radical (O2–), and increasing the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) and the concentration of glutathione (GSH), and having a positive physiological effect on the growth of osmotic stress seedlings. But the promotive effect of laser pretreatment-induced water tolerance in wheat seedling was effectively reversed by addition of 2 mmol AsA (ascorbic acid) or 5 µmol DPI (diphenyle iodonium), but exogenous 100 U/mL CAT could not reversed laser pretreatment-induced protective effect on wheat seedlings under osmotic stress. The results suggest that H2O2 metabolism was involved as signal in the processes of laser-induced water acclimation and laser-induced protective effect was shown to be likely related to NADPH oxidase-dependent H2O2 production.Keywords:
laser; osmotic stress; lipid peroxidation; antioxidative system