| Potential Zn-deficiency is widespread in calcareous soil in North China, and Zn concentration and its bioavailability of wheat grain could be improved by foliar Zn application in this region, however, the balance of micronu-trients might be changed by Zn spraying. In order to investigate the effect of foliar Zn application on the micronutrient of wheat grain, field experiments were consecutively conducted in the first(2005~2006) and the second(2006~2007) cropping seasons. The results showed that there was no signifcant effect of foliar Zn application on the yield of wheat
grain compared to no Zn supply. In the first and second cropping seasons, beside that the grain Zn concentrations were increased by 51.7% and 73.5% on average under the condition of Zn spraying at different growth stage compared to no Zn supply, and Fe concentrations were also increased by 12.4% and 12.9%; there were no significant efet of Zn spraying at jointing and flowering stages on the Cu concentration in wheat grain, but foliar Zn application at early grain filling and late grain illing stages decreased the Cu concentration, and there was no significant effect of Zn spraying on the grain Mn concentration; the phytic acid concentation decreased by 11 .06% and 16.92% under the condition of Zn spraying compare to no Zn supply, respectively. N fertilization decreased grain Mn concentration, but increased the total content of Zn + Fe+ Mn + Cu, and it decreased the phytic acid concentration of wheat grain. In conclusion, the Zn and
Fe concentration of wheat grain can be increased by foliar Zn application on potentially Zn-deficient calcareous soil, and
synergistic effect occurred in wheat grain when foliar Zn application was conducted; Zn spraying increased the total con-tent of micronutrients, and at the same time, it also improved the bioavailability of grain micronutrients. |