【文献题目】 Water Polishing improved controlled-release characteristics and fertilizer efciency of castor oil-based polyurethane coated diammonium phosphate
【作者】 Hao Lu, HongyuTian, Min Zhang，et al.
Four treatments were carried out to verify the fertilizer efciency of CDAP:
(1) without phosphate fertilizer (P0);
(2) DAP (P1);
(3) 40% CDAP with 60% DAP (C40P1);
(4) 60% CDAP with 40% DAP (C60P1).
Te amount of phosphate ertilizer applied to all treatments with phosphate fertilizer was 3.2 g P2O5 pot-¹. Te CDAP used in the pot experiment was WAT2 with 3% coating materials. Except for DAP and CDAP, the rest of nitrogen and phosphate fertilizer was supplied by common urea and calcium superphosphate, respectively. Te nitrogen application amount of all treatments was 3.2 gN pot-¹. Te application rate of potassium is 1.6 g K2O pot-¹ as potassium chloride. All fertilizers were mixed evenly in 15 kg soil and put into a pot
with 10 kg sand at the bottom.
Auxin (IAA), gibberellin (GA), phosphoenolpyruvate carboxylase (PEPC), ADP-glucosepyrophosphorylase (AGPase), phosphoribosyl pyrophosphate (PRPP),adenosine monophosphate synthetase (AMPSS) and phosphoribosyl pyrophosphate aminotransferase (PRPPAT) were extracted and assayed with a ELISA kit from Shanghai HengYuan Biological Technology Co. Ltd. (Shanghai, China). Soil available P content was extracted with 0.5 mol L-¹ sodium bicarbonate solution, and the absorbance was measured by spectrophotometer afer molybdenum and antimony. Phosphorus use efciency (PUE)=(P accumulation in P area - accumulation of P in blank area)/P application rate × 100%