Effect of long-term fertilization on wheat yield under different precipitation patterns.

Rational application of nitrogen and phosphorus is one of the main pathways to enhance wheat yield. The optimum dosage of nitrogen and phosphorus used in different precipitation patterns was studied using the binary quadratic regression equation, which could provide a basis for fertilization of wheat in Loess Plateau. The results showed that the amount of nitrogen and phosphorus ferti-lizer required for the maximum yield was dependent on precipitation patterns.