Abstract: With the highyielding winter wheat cultivar Jimai 22 as test material, a field experiment was conducted in Yanzhou of Shandong to examine the effects of regulated deficit irrigation on the water consumption and water use efficiency（WUE）of the cultivar. Five treatments were installed, i.e., the soil relative moisture content at sowing, jointing, and anthesis stages being 80%, 65% and 65% (W0 ), 80%, 70% and 70% (W1), 80%, 80% and 80% (W₂ ), 90%，80% and 80% (W₃), and 90%, 85% and 85%  (W₄)， respectively. Under the condition of 228 mm precipitation in growth season, the total water consumption was higher in treatments W₁ and W₄ than in treatments W₀, W₂, and W₃, and no difference was observed between treatments W₁ and W₄. Comparing with W₄, treatment W₁ decreased the water storage in 0-200 cm soil layer and the water consumption by wheat from jointing to anthesis stages, but increased the water consumption from anthesis to maturity stages. The water consumption rates at the stages from jointing to anthesis and from anthesis to maturity in treatment W₄ were higher. Under regulated deficit irrigation, treatment W₀ had higher WUE, but the grain yield was the lowest. The WUE in other treatments increased first, and then decreased with increasing irrigation amount. Both the water consumption and the grain yield were the highest in treatments W₁ and W₄, and treatment W₁ had higher irrigation water use efficiency and irrigation benefit than treatment W₄, being the best irrigation regime of high-yielding and water-saving in our study.

Key words: winter wheat, regulated deficit irrigation, water consumption characteristics, water use efficiency, biocontrol agents, pepper bacterial wilt, soil microbial community, Biolog.