Effect Of Fertilizers’ Rates, Precipitations And Slope Positions On The Spring Corn Yield

Under the dry-farming conditions, corn yield is influenced by many factors which can beclassified as climate, soil and fertilization except the corn cultivars. Estimation of these factorsmay be helpful to increase the corn yield. A field experiment was designed to study the fertilizerrecommendation, effect of precipitation and slope position on the corn yield on black soils innortheast China by using four consecutive years’ data according to the “3414” experimentaldesign principle. The results showed that1) main factors influencing the corn yield are the in-season precipitation, slope position,nitrogen rate and soil nitrogen content. The most important factor is the in-seasonprecipitation with which corn yield is positively and significantly correlated.2) when the precipitation in growing season （PGS） is bigger than280mm, corn yieldincreases with nitrogen rate markedly; but when the PGS is less than280mm, nosignificant increase in corn yield is observed.3) fertilization increased the water use efficiency （WUE）. Compared to no fertilization, theoptimal fertilization increased the WUE by24.3%;4) the recommended nitrogen, phosphorus and potassium fertilizer rates are respectively172kg ha^-1,32.52kg ha^-1, and129.0kg ha^-1by using response models andlinear-plus-plateau model, while they are respectively94.0kg ha^-1,22.5kg ha^-1（P₂O₅）,and37.5kg ha^-1（K₂O） by ANOVA, mach lower than results from response model andlinear-plus-plateau method.5) The NUE was positively correlated with corn yield and inversely correlated withnitrogen rates. Increase in yield and appropriate nitrogen rates may keep the NUE athigher level.