Effects of lead and zinc on three plants growth under solution culture

The influence of Pb,Zn and Pb-Zn combined interaction on the seed germination and growth of three typical plants under solution culture condition was analyzed in detail in this paper.Results showed that the three plants growth was much more restrained distinctly with Pb-Zn combined interaction than Pb or Zn separately.The influence of Pb on the growth of three plants was minor.Furthermore,as one of necessary trace element to plants,there was not visible suppression determined when the concentration of Zn was lower than 150 mg/L.In three determined plants,corn(Zea Mays) showed higher tolerant characteristics to Pb-Zn combined interaction.The stem length of corn could still reach 40% of the controlled sample even the heavy metal concentration reached 150 mg/L,which was 2 times and 2.3 times to ryegrass(Lolium perenne) and Alfalfa(Medicago Sativa) separately.The suppression of Pb and Zn to plants was concentrated in roots much more than stem and leaves.At the same time,the chlorophyll contents were reduced with the enhancement of Pb and Zn heavy metal in culture solution to inhibit the growth and development of plants.