biologia plantarum

Biologia plantarum 61:785-790, 2017 | DOI: 10.1007/s10535-017-0710-2

Responses of Pinus massoniana seedlings to lead stress

L. L. Zhang^1,2, X. M. Zhu^1,3, Y. W. Kuang^1,2,*

¹ Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Chinese Academy of Sciences, Guangzhou, P.R. China

² Guangdong Provincial Key Laboratory of Applied Botany, Chinese Academy of Sciences, Guangzhou, P.R. China

³ Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, P.R. China

To investigate the biochemical and physiological responses of Masson pine (Pinus massoniana Lamb.) seedlings to lead stress, needles, stems, and roots of two-year-old seedlings were treated with ²⁰⁷PbCO₃ for 33 d and then analyzed 1 and 7 d after the treatment was completed. Chlorophyll (Chl) b responded more sensitively than Chl a to needle Pb treatment, and the Chl content in the needles significantly decreased after Pb application to roots. The malondialdehyde and proline content remained almost unchanged, but superoxide dismutase and catalase activities increased on day 1 after all ways of Pb application. The reduced glutathione (GSH) content and GSH/oxidized glutathione ratio increased on day 1 after Pb application to stem or needles compared to the controls. At 7 d after the Pb application, the increase in dehydroascorbate (DHA) content and the decrease in the ascorbate (AsA)/DHA ratio implied a decreased antioxidant capacity of AsA. The results indicated that the antioxidants were sensitive to the Pb treatments and might be involved in the Masson pine tolerance to Pb stress.

Keywords: ascorbate; catalase; chlorophyll; glutathione; malondialdehyde; Masson pine; proline; superoxide dismutase

Subjects: lead; chlorophyll; malondialdehyde; proline; catalase; superoxide dismutase; ascorbate; glutathione; Masson pine

Received: May 10, 2016; Revised: October 4, 2016; Accepted: October 14, 2016; Published: December 1, 2017  Show citation