Effects of P Rate on Soil Available P, Yield and Nutrient Uptake of Maize

The dynamic of soil available P content under different P fertilizer application rates was investigated in grey desert soil, and the yield and nutrient uptake of maize were also evaluated with a field experiment in 2011 and 2012. The four P application rates were set as 0, 75, 150 and 300 kg/ha, noted as P0, P75, P150, and P300, respectively. The results showed that soil available P contents decreased significantly under P0 and P75 treatments. Soil available P kept balance under P150 treatment, but was extremely accumulated in 0-40 cm soil under P300 treatment. The dry matter weight of maize was increased by P application, but there were no significant differences when P application rate was high(150 kg/ha). The N and P accumulations of maize plant were increased with P application rate increased. The P application rate had no significantly effects on P distribution proportion in different plant organs of maize, but the N transportation to grain was significantly promoted by P application. N distribution proportions in grain of maize under P300 and P150 treatments were higher than those under P75 and P0 treatments. The yield of maize were also increased by P application. Therefore, the P application rate at 150 kg/ha was the optimum to the soil available P and maize yield.