Article ID Journal Published Year Pages File Type
4554553 Environmental and Experimental Botany 2013 10 Pages PDF
Abstract

Ethylene has been reported to play an essential role in the response of Arabidopsis to salinity and K+ deficiency. It was proposed that plant's ability to maintain potassium (K+) and minimize sodium (Na+) in tissues of salinity plants is critical for salt tolerance (ST). It is still unclear how ethylene modulates plant ion homeostasis under saline occasions. We employed Arabidopsis wild type (Col-0), ethylene insensitive mutants (ein2-5 and ein3-1) and constitutive triple response mutant (ctr1-1) plants to compare their phenotypic and physiological responses to salinity. Ethephon applied to plants could convert quickly to ethylene and here was applied exogenously to Col-0 seedlings to validate ethylene role in salt response. We showed that ethylene insensitivity in ein2-5 or ein3-1 plants increased Arabidopsis salt sensitivity than in Col-0. However, the salinity-induced adverse effects on Chlorophyll a/b, photosystem II function (Fv/Fm) and redox state were largely amended in the ctr1-1 than in Col-0 plants with the severe salinity. The compatible solute sucrose and antioxidant system were also up-regulated to improve ST in ctr1-1 plants. The ethephon obviously alleviated the salinity-induced restriction in root length. The subsequent analysis on the Na+ and K+ homeostasis found that ethylene could help plant retain higher shoot or root K+ nutrition in the short- or long-term salt-stressed plants. However, the ethylene did not significantly alter sodium buildup and water relation in the salt-stressed plants. Our observations confirmed the key role of ethylene in improved plant ST and highlighted the ethylene ability to retain K+, rather than decreasing Na+, in shoots and roots to improve Arabidopsis ST.

Research highlights▶ Ethylene signaling help improve Arabidopsis salt tolerance. ▶ Improved salt tolerance relates to higher K+ and K+/Na+ ratio. ▶ Ethylene signaling modulates antioxidant systems and compatible adjustment. ▶ Exogenous ethephon retains salt-induced K+ loss.

Related Topics
Life Sciences Agricultural and Biological Sciences Ecology, Evolution, Behavior and Systematics
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