Abstract:

To clarify yield distribution and fertilization effect of maize in the Yellow River Delta, this study analyzed 143 sets of data of maize filed experiments in different sector areas from 2010 to 2020, in which yield distribution, fertilizer use efficiency, yield gap contribution efficiency, relative yield, agronomic efficiency and partial factor productivity of nitrogen, phosphorus and potassium fertilizers were analyzed. The results showed that with an average yield of 6.81 t/hm², maize yield varied greatly from 2.63 to 9.52 t/hm² in different sector areas. The maize yield in the second sector was significantly lower than that in the first and third sectors. Applying nitrogen fertilizer increased maize yield by 40.88%, while phosphorus fertilizer by 8.49% and potassium fertilizer by 2.18%. Based on the model simulation of Boundary line, the yield gap was 3.01 t/hm², and the gap of high yield records was 2.49 t/hm². The yield gap contribution efficiency of nitrogen was the largest, followed by phosphorus fertilizer and potassium fertilizer. The relative yields of N, P and K fertilizer were 0.76, 0.99 and 1.05, respectively. The agronomic efficiency and partial factor productivity of nitrogen fertilizer were 8.64 and 33.78 kg/kg, while 2.85 and 86.12 kg/kg for phosphorus fertilizer, and 17.97 kg/kg and 148.01 kg/kg for potassium fertilizer. Nitrogen was the first limit factor of maize yield, which had a good effect on yield increasing, followed by phosphorus and potassium. Reducing nitrogen input and improving soil in the Yellow River Delta were effective measurements to decrease yield gap of maize, which will be helpful for increasing yield and saving fertilizer.

Key words: corn, Yellow River Delta, yield increase, fertilizer efficiency