Effects of Zinc on the Growth of Several Vegetables

Heavy metal zinc is one of the trace elements necessary to the growth of vegetable, but Zn excessiveness also could cause damage. In this research, four vegetables were planted by soil culture method under different Zn2+concentration controlled by the exogenous Zn2+addition; their growth characteristics were analyzed to find the sensitive growth indexes to Zn and compare their tolerance to Zn pollution. Results show that: low concentration of Zn2+(< 100 mg/kg) can promote significantly the plant height and the root length growth of all the four vegetables, while, as the exogenous Zn2+increased to the concentration of 150 mg/ kg, the number of leaves, the above-ground dry biomass and the underground dry biomass were suppressed significantly; in this experiment, the four vegetables appeared different sensitivity to Zn stress,Lactucasativavar.longifoliafappeared highest tolerance andBrassicachinensisappeared less sensitivity to Zn stress.