ScienceAsia 42(2016): 323-331 |doi:
Effects of arbuscular mycorrhizal fungi on caesium accumulation and the ascorbate-glutathione cycle of Sorghum halepense
Ren-Hua Huanga,b, Yun-Mei Lub, Hui-Ling Yanga,b, Wei Huanga,b, Ke Chena,*
ABSTRACT: A pot experiment was conducted to study the effects of Glomus mosseae and Glomus versiforme on the ascorbate-glutathione cycle metabolism and caesium enrichment in roots and leaves of Sorghum halepense. The results showed that inoculated G. mosseae and G. versiforme significantly increased the concentrations of ascorbate (AsA) and reduced glutathione (GSH), the ratios of AsA/DHA (dehydroascorbate) and GSH/GSSG (oxidized glutathione) in roots and leaves of S. halepense in Cs contaminated soil. Additionally, the inoculated arbuscular mycorrhizal fungi increased the antioxidant enzyme activities of the ascorbate-glutathione cycle, with the best efficiency provided by G. mosseae. The activities of antioxidant enzymes (ascorbate peroxidase, APX, EC 188.8.131.52; dehydroascorbate reductase, DHAR, EC 184.108.40.206; and glutathione reductase, glutathione reductase (GR), EC 220.127.116.11) in the roots were, respectively, 4.7, 3.6, and 2.3 times higher than those in non-inoculated roots, and the activities of DHAR was 1.7 times higher than that in non-inoculated leaves. However, G. versiforme increased the activity of monodehydroascorbate reductase (MDHAR, EC 18.104.22.168) 2.39 U/g fresh weight, and the activities of APX and GR were 6.8 and 1.4 times higher than for nonmycorrhizal plants. G. versiforme also increased the accumulation of caesium in roots and leaves but to a lesser extent than G. mosseae, and with a positive effect on translocation. Thus arbuscular mycorrhizal fungi promotes efficient operation of ascorbate-glutathione cycle in the roots and leaves of S. halepense, enhancing its tolerance to Cs stress.
||Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
||College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
* Corresponding author, E-mail: email@example.com
Received 27 Aug 2014, Accepted 0 0000