biologia plantarum

Biologia plantarum 58:676-680, 2014 | DOI: 10.1007/s10535-014-0440-7

Stomatal closure in sweet potato leaves induced by sulfur dioxide involves H₂S and NO signaling pathways

K. -D. Hu¹, J. Tang², D. -L. Zhao², L. -Y. Hu¹, Y. -H. Li¹, Y. -S. Liu¹, R. Jones³, H. Zhang^1,*

¹ School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, P.R. China

² Xuzhou Sweet Potato Research Center, National Sweet Potato Improvement Center, Xuzhou, P.R. China

³ Department of Plant and Microbial Biology, University of California, Berkeley, USA

Sulfur dioxide (SO₂) is a well-known and widespread air pollutant but it also acts as signaling molecule in various processes in animals. However, there is limited information on the role of SO₂ in plants except of its toxicity. Here we studied the role of SO₂ on stomatal movements in sweet potato (Ipomoea batatas) leaves. SO₂, generated by Na₂SO₃/NaHSO₃ solutions, was applied on epidermal strips. We found that the SO₂ donor induced stomatal closure in a dose-dependent manner. Rapid increases in endogenous hydrogen sulfide and nitric oxide content levels were observed in leaves after the treatment with the SO₂ donor. The SO₂-induced stomatal closure was reversed by the H₂S scavenger hypotaurine and the NO-specific scavenger cPTIO. Our results indicate that the SO₂-induced stomatal closure was likely mediated by the H₂S and NO signaling pathways.

Keywords: abscisic acid; gaseous signals; sulfur metabolism

Subjects: stomatal aperture; sulphur dioxide; nitric oxide; abscisic acid; sweet potato

Received: October 17, 2013; Revised: March 19, 2014; Accepted: April 23, 2014; Published: December 1, 2014  Show citation