Regulated Deficit Irrigation Effect of Winter Wheat as Affected by Different Fertilizer Application Treatments

Field and pot experiments were conducted to evaluate the effect of fertilizers (no fertilizer (F0), compound fertilizer (F1) and organic fertilizer+compound fertilizer (F2) on wheat under water stress (RD1 (waterdeficit at flowering-milking stage), RD2 (water deficit at returning green-jointing stage) and RD3 (water deficit at returning green-jointing and flowering-milking stage). The control plants (CK) were subjected to 60-75% field water capacity (FWC) in the whole growing stage. The results showed that different fertilizer treatments had different effects on winter wheat with RDI treatments. At flowering stage, RD2 and RD3 lowered significantly population quantity, leaf area, plant height and dry weight per shoot of winter wheat in both F0 and F1 treatments. In F2 treatment, RD2 and RD3 lowered significantly plant height and leaf area and but had no significant effects on population quantity and dry weight per shoot of winter wheat. At jointing stage, RD2 and RD3 lowered significantly water use efficiency of leaf level (WUEleaf) in F0 treatment, but increased WUEleaf of winter wheat in F1 and F2 treatments. At flowering stage, RD2 had no effect on photosynthetic rate (P-N), transpiration rate (Tr) and WUEleaf of winter wheat. RD3 lowered significantly P-N and Tr of wheat, but had no effect on WUEleaf in F0 treatment. In F1 treatment, RD2 and RD3 had similar P-N, Tr and WUEleaf with CK. In F2 treatment, RD2 increased significantly P-N, but had no effect on WUEleaf of winter wheat. RD3 had no effect on P-N and but improved WUEleaf by lowering Tr of winter wheat. RD2 lowered grain yield of winter wheat in F0 and F1 treatments, but had no effect on grain yield in F2 treatment. RD3 significantly reduced the grain yield in 3 fertilizer treatments. In addition, grain yield stability (GYS) of winter wheat in F2 treatment was higher than those in F0 and F1 treatments under the same RDI treatment. In conclusion, appropriate RDI and fertilizer treatment can significantly increase WUEleaf and grain yield stability of winter wheat. (C) 2018 Friends Science Publisher