Gas-exchange, photo- and antioxidant protection, and metal accumulation in I-214 and Eridano Populus sp clones subjected to elevated zinc concentrations

作者：Fernandez Martinez Jordi; Zacchini Massimo; Fernandez Marin Beatriz; Ignacio Garcia Plazaola Jose; Fleck Isabel^*

来源：Environmental and Experimental Botany, 2014, 107: 144-153.

DOI：10.1016/j.envexpbot.2014.06.004

• Antioxidant
• Heavy metal
• Phytoextraction
• Phytoremediation
• Hydroponics
• Poplar

Rooted cuttings of Eridano and I-214 Populus clones were treated in hydroponics with high [Zn] to establish their phytoextraction capacity and physiological responses for phytoremediation. The Bio-concentration factor, Uptake ratio and Translocation factor revealed that the highest Zn accumulation occurred in roots. Lower accumulation at 1 mM [Zn] in Eridano aerial parts limited Zn toxicity on photosynthetic machinery. Increasing [Zn] negatively affected growth, net photosynthesis, stomatal conductance, maximum quantum yield, chlorophyll content and hydric parameters. The physiological impairment in I-214 at 1 mM [Zn] indicated a greater sensitivity to high [Zn] than Eridano. At 5 mM [Zn], high toxicity for both clones occurred. Upregulation of photoprotective and antioxidant responses was a consequence of Zn stress rather than a Zn tolerance mechanism. Increased de-epoxidation state of the xanthophyll-cycle, alpha-Tocopherol and reduced glutathione and decreased total phenolics in I-214 at 1 mM [Zn] suggested that it responded earlier to oxidative stress when compared to Eridano.

• 出版日期2014-11