Effects of Cu²⁺ on Wheat Seedlings Exposed to Enhanced Ultraviolet-B Radiation

Liyan Yang¹, Zhaoqing Wang¹, Yuqi Hou¹, Rong Han¹, Yi Sun^2,3*

¹Shanxi Normal University, Linfen, China.
²Biotechnology Research Centre, Shanxi Academy of Agricultural Sciences, Taiyuan, China.
³Key Laboratory of Crop Gene Resources and Germplasm Enhancement on Loess Plateau, Ministry of Agriculture, Taiyuan, China.

DOI: 10.4236/ajps.2014.520322                

Abstract

To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L^-1 CuCl₂ solution was irrigated to Triticum aestivum L. cv. Linyuan 2069 one day after germination with or without ultraviolet-B (10.08 kJ m^-2·d^-1) light exposure, respectively. The results showed that Cu²⁺ and UV-B caused various adverse effects on wheat seedling development. Cu²⁺ hindered root development by significantly reducing root number, while UV-B dwarfed seedling height and decreased the leaf length. Chlorophyll content and activity of ATPase in thylakoid membrane of wheat leaves dropped significantly under enhanced UV-B while the activity of ATPase in plasma membrane of seedling root was significantly decreased in Cu²⁺ group. Relative electric conductivity of leaves significantly increased in both Cu²⁺ and UV-B groups, so did the biomass. We also observed that combined Cu²⁺ and UV-B showed more adverse effects on wheat seedlings than either of them alone except for root growth.

Keywords

Cu²⁺, Seedling Development, UV-B Radiation, Wheat

Conflicts of Interest

The authors declare no conflicts of interest.

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