Distribution Characteristics of Salt Ions and Heavy Metals in Tomato Under Salinity Stress

The distribution of salt ions(Na+,K+,Ca2+) and heavy metal ions(Cd2+,Pb2+,Cr2+,Zn2+,Cu2+,Ni2+) in different organs of tomatoes grown in the soils with eight salinity levels was surveyed using a pot experiment.The influence of salt ions on uptake of heavy metal by tomato was investigated.The results showed that Na+ contents within roots,shoots,leaves and fruits increased as soil salinity increased.K+ contents in roots rose slightly,K+ contents in shoots decreased significantly,while contents of K+ in leafs remain unaltered from treatment two to treatment eight.Ca2+ contents in different parts of tomato also didn't change along with the soil salinity.The contents of Cd,Pb,Cr,Zn and Cu in roots,and Cd in shoots and leaves increased along with the rise of soil salinity.However,the contents of Ni in roots,Pb,Cr,Zn,Cu and Ni in shoots and leaves and all six heavy metals within fruits were not significantly influenced by soil salinity.It was concluded that the increase of soil salinity had positive effect on the uptake of heavy metals by the roots of tomatoes,except for Ni.The results provide some useful scientific information for the agricultural land use of saline soils polluted by heavy metals.