Abstract: 【Objective】Dry and soil leanness are two limiting factors in arid and semi-arid areas. So it has been attached great importance on the effect of irrigation and fertilization, as well as its influence on yield of corn. 【Method】 The micro-spot trials were carried out in rain-protection shed under the condition of drip fertigation by"311-B"D-saturation optimum design. 【Result】The regressive maths model was set up based on the corn yield by quadratic regression analysis. Analysis showed that the dosage of N fertilizer significantly influenced the yield of corn. And then are volume of irrigation and the rate of P fertilizer. The interaction effects among these factors were positive on the corn yield with the influenced order as N and water>P and water>N and P. From the corn yield aspect, higher level of N and P, sufficient water is the best combination. 【Conclusion】The optimum combinations of N and P were 243.27 kg·ha-1and 137.431 kg·ha-1 respectively, with lower irrigation limit of 65.6% field capacity under the conditions of this experiment.

Key words: Drip fertigation, Water and fertilizer, D-saturation optimum design, Corn