Abstract. The role of gibberellin (GA) and ethylene in submergence-induced petiole elongation was studied in two species of the genus R u m e x. Analysis of endogenous GAs in the flooding-tolerant R u m e x pa/ustris Sm. and the intolerant R u m e x acetosa L. by gas chromatographvmass spectrometry showed for both species the presence of GA], G A 4, G A 9, G A 19, G A 20 and G A 53. Gas chromatography-mass spectrometry analysis of R. palusiris petiole tissue of submerged plants showed an increase in levels of 13-OH GAs, especially G A h compared with drained plants. This effect could be mimicked by application of 5 f.tL L_l ethylene. In R. acetosa, no differences between levels of GAs in drained or submerged plants were found. In R. p a lu stris, both submergence and ethylene treatment sensitized petioles to exogenous gibberellic acid (GA3). In R. acetosa the effect was opposite, i.e. submergence and ethylene de-sensitized petioles to G A 3. Our results demonstrate the dual effect of ethylene in the submer gence response related to flooding tolerance, i.e. in the flooding-tolerant R. palustris ethylene causes an increased concentration of and sensitivity to GA with respect to petiole elongation while in the intolerant R. acetosa ethylene reduces growth independent of GAs.
Abstract. The role of gibberellin (GA) and ethylene in submergence-induced petiole elongation was studied in two species of the genus R u m e x. Analysis of endogenous GAs in the flooding-tolerant R u m e x pa/ustris Sm. and the intolerant R u m e x acetosa L. by gas chromatographvmass spectrometry showed for both species the presence of GA], G A 4, G A 9, G A 19, G A 20 and G A 53. Gas chromatography-mass spectrometry analysis of R. palusiris petiole tissue of submerged plants showed an increase in levels of 13-OH GAs, especially G A h compared with drained plants. This effect could be mimicked by application of 5 f.tL L_l ethylene. In R. acetosa, no differences between levels of GAs in drained or submerged plants were found. In R. p a lu stris, both submergence and ethylene treatment sensitized petioles to exogenous gibberellic acid (GA3). In R. acetosa the effect was opposite, i.e. submergence and ethylene de-sensitized petioles to G A 3. Our results demonstrate the dual effect of ethylene in the submer gence response related to flooding tolerance, i.e. in the flooding-tolerant R. palustris ethylene causes an increased concentration of and sensitivity to GA with respect to petiole elongation while in the intolerant R. acetosa ethylene reduces growth independent of GAs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.