Effects of Zn stress on physiological response and accumulation of three herbs

Pot experiments were conducted to study the growth of three herbs (Spodiopogon sibiricus, Penniseturn alopecuroides, Panicum virgatum) on Zn-polluted soil with five concentrations (62.5, 125, 250, 500, 1 000 mg·kg-1). Physiological indices and Zn concentration in the three herbs were measured to assess the tolerance and accumulation for Zn pollution. Aboveground biomass of P.virgatum reduced by 68.2% in Zn treatment 1 000 mg·kg-1 and belowground biomass reduced by 70.5% compared with control. The aboveground biomass and belowground biomass of P.alopecuroides reduced by 33.7% and 69.7% respectively. The biomass of S.sibiricus has no significant difference compared with control, the tolerance was S.sibiricusP.alopecuroidesP.virgatum. The physiological indices of the three herbs had significant change, and the change was S.sibiricusP.alopecuroidesP.virgatum. The accumulation of three herbs for Zn were P.alopecuroidesS.sibiricusP.virgatum. For P.alopecuroides, the accumulation of aboveground and belowground reached the highest value of 156.38 mg·kg-1 and 303.51 mg·kg-1 in the treatment 1 000 mg·kg-1.