In this study

the effects of irrigation and fertilizer coupling on production performance of Lycium barbarum L. were investigated and the irrigation scheduling was optimized based on water and nitrogen coupling. The study adopted two factors of drip irrigating water quota (W) and amount of nitrogen application (F). W included 225 (LW)

300 (MW) and 375 m3/hm2 (HW)

respectively

and F included 480 (LF)

629 (MF)

and 777 (HF) kg/hm2. There were 9 treatments combined by W and F with three levels for each: T1 (LW

LF)

T2 (LW

MF)

T3 (LW

HF)

T4 (MW

LF)

T5 (MW

MF)

T6 (MW

HF)

T7 (HW

LF)

T8 (HW

MF) and T9 (HW

HF). The field experiments were conducted in Zhongning county

Ningxia Hui Autonomous Region

Northwest China in 2014 and 2015.The results showed that the yield increased with the increasing irrigation water quota with maximum yield of 1 335.7 kg/hm2 of HW for four-year-old tree under the same fertilizer condition

the yields of MW and LW were 1 174.2 and 1 066.5 kg/hm2

respectively. The maximum yield was MW by 2 556.1 kg/hm2 for the five-year-old

and the yields of HW and LW were 2 463.7 and 2 394.5 kg/hm2

respectively. Under the same irrigation level treatment

the yield was the highest in the MF treatment and lowest in the LF treatment for 2 years experimental results. The yields of HF

MF and LF were 2 595.5

2 758.0 and 2 407.0 kg/hm2

respectively for the four-year-old

and 3 652.3

4 113.9 and 3 532.1 kg/hm2

respectively for the five-year-old. The results of 2 years experiments showed that yield climbed up from LF to MF and declined from MF to HF. There was no consistency of yield with irrigation water quota in 2 years experiments. We optimized the irrigation scheduling with the methods of this study

the results showed that the total ETa of the one-year-old Lycium barbarum L. was 166.0~198.8 mm

and 194.7~252.5

196.6~227.2

173.5~221.6 and 179.3~196.6 mm

respectively for the two-

three-

four- and five-year-old tree. This attributed to the consumption of fertilizer and fertilizer use efficiency increased with tree-age increase

as well as the increased irrigation or fertilizer couldn’t promot yield of Lycium barbarum L.. It is necessary that water and fertilizer should get perfect coupling. This study would be as reference of optimized irrigation scheduling of ideal yield for ‘Ningqi No.1’ with 1 to 5 years tree-age.