STUDY ON THE CELL NUTRITION OF PHOSPHORUS AND ZINC INTERACTION IN CORN AND WHEAT

The cellular nutrition of phosphorus and zinc and their interaction in corn and wheat under the varied phosphorus and zinc were investigated in solution culture. The results showed that the increased phosphorus content of cell walls, cytoplasm and vacuoles in both leaved and roots of corn and wheat were observed with the increasing phosphorus supply (0, 0.12, 0.6, 3.0 mmol/L) in the medium. However, the content of phosphorus in the cell wall was higher than that in the cytoplasm. The enhanced phosphorus in the culture solution increased the content of zinc in the root cell wall, but the treatment of 3 mmol/L P made the zinc content in cytoplasm and vacuoles decreased. High treatment with phosphorus inhibited the zinc translocation from roots to shoots in both crops. In addition, as most of zinc in leaves was bound to in the cell wall, a relative low zinc contents in the leaf cytoplasm and vacuoles were expected compared to the treatment of rich zinc supply (2.0 mol/L) and decreased application of zinc (0.1 mol/L) increased the content of phosphorus in the leaf and root cell in corn and wheat. As a result, the stunted growth of both crops was attributed to the imbalance of low zinc and high phosphorus concentrations in the plants.