Silicon-mediated Mitigation of Wounding Stress Acts by Up-regulating the Rice Antioxidant System
Silicon (Si) is essential for normal growth and development in plants and is also beneficial for their responses to wounding. However, the mechanisms by which Si acts to mitigate the effects of wounding is not fully understood. This effect possibly occurs through a reduction in the oxidative stresses associated with wounding. Here, we tested this possibility by investigating the effects of applying different concentrations of Si (0,5 and 1,0 mM) to rice plants under wounding stress for a period of 6 and 12 h. We found that a higher uptake of Si was signifiacntly associated with an increase in leaf chlorophyll contet. In response to wounding induced oxidative stress, the extent of lipid bilayer peroxidation was reduced in a dose-dependent manner by Si application for 6 or 12 h. Activity of the catalase enzyme was initially lowered by Si treatment; however, at 1.0 mM Si, catalase activity increased significantly after 12h of wounding stress. A similar response was also observed for a peroxidase enzyme. Polyphenol oxidase showed a significant reduction in activity. We conclude that Si application does not only improve leaf chlorophyll content but can also overcome the oxidative stress due wounds or physical injuries.
Keywordssilicon antioxidant enzymes wounding stress lipid peroxidation Oryza sativa japonica time and dose dependent effect
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This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2014R1A1A2A10058022).
- Araji, S., Grammer, T.A., Gertzen, R., Anderson, S.D., Mikulic-Petkovsek, M., Veberic, R., Phu, M.L., Solar, A., Leslie, C.A., Dandekar, A.M., Escobar, M.A. 2014. Novel roles for the polyphenol oxidase enzyme in secondary metabolism and the regulation of cell death in walnut (Juglan sregia). Plant Physiol. 164:1191–1203.PubMedPubMedCentralCrossRefGoogle Scholar
- Eraslan, A.I., Pilbeam, D.J., Gunes, A. 2008. Interactive effects of salicylic acid and silicon on oxidative damage and antioxidant activity in spinach (Spinacia oleracea L. cv. Matador) grown under boron toxicity and salinity. Plant Growth Regul. 55:207–219.Google Scholar
- Hamayun, M., Sohn, E.Y., Khan, S.A., Shinwari, Z.K., Khan, A.L., Lee, I.J. 2010. Silicon alleviates the adverse effects of salinity and drought stress on growth and endogenous plant growth hormones of soybean (Glycine Max L.). Pak. J. Bot. 42:1713–1722.Google Scholar
- Kim, Y.H., Khan, A.L., Hamayun, M., Kang, S.M., Lee, I.J. 2012. Silicon treatment to rice (Oryza sativa L. cv. ‘Gopumbyeo’) plants during different growth periods and its effects on growth and grain yield. Pak. J. Bot. 44:891–897.Google Scholar
- Kim, Y.H., Khan, A.L., Kim, D.H., Lee, S.Y., Kim, K.M., Waqas, M., Jung, H.Y., Shin, J.H., Kim, J.G., Lee, I.J. 2014a. Silicon mitigates heavy metal stress by regulating P-type heavy metal ATPases, Oryza sativa low silicon genes, and endogenous phytohormones. BMC Plant Biol. 14:13.PubMedPubMedCentralCrossRefGoogle Scholar
- Ma, J.F., Takahashi, E. 2002. Soil, Fertilizer, and Plant Silicon Research in Japan. Elsevier Science, B.V. Amsterdam, The Netherlands.Google Scholar
- McAvoy, R.J., Bible, B.B. 1996. Silica sprays reduce the incidence and severity of bract necrosis in Poinsettia. Horti. Sci. 31:1146–1149.Google Scholar
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