Effects of long-term P fertilization on P and Zn availability in winter wheat rhizoshpere and their nutrition

The effects of long-term P application on the available P and Zn in rhizoshpere soil,P and Zn concentration in grain of winter wheat were studied on the 20 years long-term experiment station in Beijing.The main results were as follows: soil Olsen-P concentration significantly increased with long-term high P fertilizationP2O5 135 kg/(ha a).DTPA-Zn concentration in rhizosphere was significant higher than that in bulk soil.P concentration in shoot of winter wheat both at shooting stage and heading stage was apparently improved with increasing P application rates.Whereas,Zn concentration in shoot of winter wheat treated with long-term P fertilization was significantly lower than that of no P supply at heading stage.The P/Zn ratio in winter wheat plant was significantly enhanced with increasing P application rate both at shooting stage and heading stage.Compared with no P treatment,P2O5 67.5 and 135 kg/(ha a) application significantly increased P concentration and decreased Zn concentration in grain of winter wheat.As the results observed,P/Zn ratio in winter wheat grain was significantly increased.A significantly negative relationship between P and Zn concentration in winter wheat grain was observed.