The main findings of this study are summarized in
Fig. 5. In non-autoclaved soil, higher P supply reduces
tissue Zn concentrations of wheat in both Zn-deficient
and Zn-sufficient conditions, primarily by suppressing
mycorrhizal activity. This effect disappears in
autoclaved soil, where AM fungi have been eliminated.
Solution culture conditions are in this respect representative
for autoclaved soil. All these results indicate that
the well-documented negative effect of high P on tissue
Zn concentration is mycorrhiza-dependent. By avoiding
excessive P fertilization and implementing AMstimulating
agronomic practices, P-induced losses to
Zn concentrations may be minimized. The AMmediated
P–Zn interaction in wheat should also be
considered in biofortification of cereal grains with Zn