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Indexed by:期刊论文

Date of Publication:2017-01-01

Journal:PLANT SCIENCE

Included Journals:SCIE、PubMed

Volume:254

Page Number:1-11

ISSN No.:0168-9452

Key Words:Dianthus chinensis L.; Hyperhydricity; Silver nitrate; Reactive oxygen species; Stomatal aperture; Ethylene

Abstract:Hyperhydricity occurs frequently in plant tissue culture and can severely affect commercial micropropagation and genetic improvement of the cultured plantlets. Hyperhydric shoots are charaterzized by high water content, but how this occurs is still a subject of investigation. Silver ion (Ag+) can reduce the extent of hyperhydricity in plants, but its effect on the reversion of hyperhydric plantlets and the underlying mechanism of reversion has not been clarified. In this study, about 67% of the hyperhydric Dianthus chinensis L. plantlets were found to revert to normal condition when the plantlets were cultured in medium supplemented with 29.4 mu mol L-1 AgNO3. Water content and hydrogen peroxide (H2O2) content in the guard cells of these plantlets were reduced, while stomatal aperture and water loss rate were increased. AgNO3 also reduced the content of endogenous ethylene and expression of ethylene synthesis and ethylene signal transduction-associated genes. Reduced accumulation of ethylene consequently led to an increase in stomatal aperture mediated by decreased H2O2 content in the guard cells. These results adequately verified the role of AgNO3 in the reversion of hyperhydricity in D. chinensis L. and also provided clues for exploring the cause of excessive water accumulation in hyperhydric plants. (C) 2016 Elsevier Ireland Ltd. All rights reserved.