Effects of different water-soluble phosphorus on the distribution and utilization of phosphorus in maize in Xinjiang, China.

Phosphorus (P) is the main limiting nutrient in agriculture. Most of the P fertilizers applied to the soil remain ineffective because of the weak movement and transfer of P in the soil. Current agricultural production requires large amounts of P fertilizers, leading to the accumulation of residual P in the soil and serious ecological problems. Fixation of P is a vital reason for limited fertilizer effectiveness. Therefore, improving soil P effectiveness is the key to reducing soil P accumulation. This study explored the effects of different water-soluble P fertilizers on maize yield and economic benefits by comparing the relationships between soil P distribution and P absorption and utilization of maize in calcareous soil of Xinjiang province in China. The main results indicated that (1) the drip application of ammonium polyphosphate (APP) and urea phosphate (UP) was more beneficial for increasing the total P content in the deep soil layer; the drip application of APP was beneficial in increasing the available P content of the deep soil layer. (2) Dripping acid fertilizer was more conducive to reducing soil acidity and alkalinity (pH). (3) The application of different P fertilizers favoured the accumulation of P in all organs of maize, among which APP and UP were the most effective since they increased accumulation by 75.8% and 60.4% (at the flowering stage) and 98.2% and 62.3% (at the maturity stage), respectively, compared with CK (without P fertilizer). (4) pH was the main factor affecting P uptake and transformation, and the drip application of P fertilizer had the most significant effect on pH. (5) The application of different water-soluble P fertilizers increased maize yield and economic benefits. Among the five water-soluble P fertilizers selected in this study, APP had the greatest economic benefits, followed by UP and monoammonium phosphate (MAP); they increased yields by 31.6%, 24.5%, and 22.0%, respectively, compared with CK. [ABSTRACT FROM AUTHOR]