Wound-induced Oxidative Responses in Mountain Birch Leaves
• Aims The aim of the study was to examine oxidative responses in subarctic mountain birch, Betula pubescens subsp. czerepanovii , induced by herbivory and manual wounding. • Methods Herbivory-induced changes in polyphenoloxidase, peroxidase and catalase activities in birch leaves were determined. A...
Published in: | Annals of Botany |
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Main Authors: | , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2006
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Subjects: | |
Online Access: | http://aob.oxfordjournals.org/cgi/content/short/97/1/29 https://doi.org/10.1093/aob/mcj005 |
Summary: | • Aims The aim of the study was to examine oxidative responses in subarctic mountain birch, Betula pubescens subsp. czerepanovii , induced by herbivory and manual wounding. • Methods Herbivory-induced changes in polyphenoloxidase, peroxidase and catalase activities in birch leaves were determined. A cytochemical dye, 3,3-diaminobenzidine, was used for the in situ and in vivo detection of H 2 O 2 accumulation as a response to herbivory and wounding. To localize peroxidase activity in leaves, 10 m<scp>m</scp> H 2 O 2 was applied to the dye reagent. • Key Results Feeding by autumnal moth, Epirrita autumnata , larvae caused an induction in polyphenoloxidase and peroxidase activities within 24 h, and a concomitant decrease in the activity of antioxidative catalases in wounded leaves. Wounding also induced H 2 O 2 accumulation, which may have both direct and indirect defensive properties against herbivores. Wound sites and guard cells showed a high level of peroxidase activity, which may efficiently restrict invasion by micro-organisms. • Conclusion Birch oxidases together with their substrates may form an important front line in defence against herbivores and pathogens. |
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