Effect of Pb toxicity on the growth and physiology of two ecotypes of Elsholtzia argyi and its alleviation by Zn.
Hydroponics experiments were conducted to underpin the nature of interactions between Zn, an essential micronutrient and Pb, a nonessential element on plant growth and root morphology, as well as antioxidant adaptation in mined ecotype (ME) and nonmined ecotype (NME) of Elsholtzia argyi. Plants were exposed to 50 μM Pb having normal Zn (0.5 μM), and two other treatments of the same Pb with low (0.05 μM) and high (20 μM) Zn, respectively for 12 days. Application of Pb with normal Zn caused adverse effects on the overall growth and antioxidant capacity of both ecotypes, however; effects were more pronounced in NME. The addition of high Zn along with Pb improved the growth and antioxidant capacity of both the ecotypes, while low Zn failed to show significant changes in NME plants; however slightly aggravated the Pb toxicity in the plants of ME. Zinc antagonized Pb concentrations in root and stem of both ecotypes and leaf of ME, while no significant differences were noted in Pb concentrations of NME leaf. It is suggested that in E. argyi, mechanisms of Pb and Zn uptake and translocation as well as their interactions within the plant cell may be different for both ecotypes and need to be further investigated.
Islam
Ejazul
E
Ministry of Education Key Lab of Environmental Remediation and Ecosystem Health, College of Natural Resources and Environmental Science, Zhejiang University, Huajiachi Campus, Hangzhou 310029, China. ejazulislam75@yahoo.com
Liu
Dan
D
Li
Tingqiang
T
Yang
Xiaoe
X
Jin
Xiaofen
X
Khan
Muhammad Athar
MA
Mahmood
Qaisar
Q
Hayat
Yousaf
Y
Imtiaz
Muhammad
M
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D018527:Hydroponics; D019686:Lamiaceae / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D007854:Lead / Q000378:metabolism / Q000633:toxicity*; D015227:Lipid Peroxidation / Q000187:drug effects; D051379:Mice; D018977:Micronutrients / Q000378:metabolism / Q000494:pharmacology*; D008906:Mining; D018384:Oxidative Stress / Q000187:drug effects; D009195:Peroxidase / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism; D015032:Zinc / Q000378:metabolism / Q000494:pharmacology*
D000975:Antioxidants; D018977:Micronutrients; D012989:Soil Pollutants; D007854:Lead; D006861:Hydrogen Peroxide; C121048:guaiacol peroxidase; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase; D005978:Glutathione; D015032:Zinc; D001205:Ascorbic Acid