Tolerance and Cumulative Effect of Zinc Pollution of Three Vegetables in Central China

[Objective] The aim was to study the differences of tolerance and cultivate effect of Zn pollution in three vegetables in central China. [Method] Seed germination tests and pot experiments of radish (Raphanus Sativus L.),pakchoi(Brassica campestris ssp. Chinensis) and edible amaranth (Amaranthus mangostanus) under Zn stress with different concentrations were carried out,to study the effects of different treatments on seed germination rates,seedling growth,biomass and Zn contents of vegetables. [Result] Zn stress with concentration of 2 000 mg/L had no significant influence on seed germination rates of pakchoi and radish,but had significant influences on seed germination rate of amaranth. Zn stress with concentrations of 500 and 2 000 mg/L had significant influence on seedling growth of the three vegetables. The tolerance of radish to excessive Zn toxicity was stronger than that of pakchoi and amaranth. In addition,Zn contents in edible part of the 3 vegetables in each treatment were lower than standard of food hygiene of China. When the added Zn was 100-1 000 mg/kg soil,the Zn contents in radish shoot and root parts were both lower than that in pakchoi and amaranth. [Conclusion] Radish had better tolerance on Zn pollution than pakchoi and amaranth,and was more suitable to be planted in Zn-contaminated soils than the other two vegetables in central China to reduce Zn contamination risk in food chain.