Health & Environmental Research Online (HERO)


Print Feedback Export to File
4243257 
Journal Article 
Protection of Artemisia annua roots and leaves against oxidative stress induced by arsenic 
Kumari, A; Pandey, N; Pandey-Rai, S 
2017 
Yes 
Biologia Plantarum
ISSN: 0006-3134
EISSN: 1573-8264 
ACAD SCIENCES CZECH REPUBLIC, INST EXPERIMENTAL BOTANY 
PRAHA 6 
61 
2 
367-377 
WOS:000401838400019 
The present study was conducted to examine differential responses of roots and leaves of Artemisia annua to different arsenic concentrations (50, 100, and 150 mu M) and treatment durations (1, 3, 5, or 7 d). The values of bioconcentration factor and translocation factor calculated on the basis of total As-accumulation in roots and shoots suggested that A. annua is a good As-accumulator. Above and below ground plant biomass was enhanced at 100 mu M As but at 150 mu M As was significantly reduced. As-treatment caused membrane damage more in the roots than in the leaves as reflected by higher degree of lipid peroxidation in the roots than in the leaves. In response to As stress, plants activated antioxidative defense for detoxification of induced reactive oxygen species (ROS), As sequestration via phytochelatins (PCS) as well as production of a wide range of secondary metabolites. All of them were activated differently in roots and leaves. Among enzymatic antioxidants, leaves significantly elevated superoxide dismutase (SOD), ascorbate peroxidase, and glutathione reductase, whereas in roots SOD, catalase, and peroxidase played significant role in ROS detoxification. Plants activated As-sequestration pathway through thiols, glutathione, and PCS and their respective genes were more induced in leaves than in roots. Further gas chromatography in tandem with mass spectroscopy analysis revealed differential modulation of secondary metabolites in leaves and roots to sustain As-stress. For example, roots synthesized linoleic acid (4.85 %) under As-treatment that probably stimulated stress-signalling pathways and in turn activated differential defense mechanisms in roots to cope up with the adverse effects of As. 
antioxidants; phytochelatins; reactive oxygen species; secondary metabolites