Effect of Partial Root-zone Irrigation on the Growth and Water Use of Sweet Corn under Two Fertilization Level

Partial root-zone irrigation (PRI) such as alternate partial root-zone irrigation (APRI) and partial root-zone drying (PRD) is a new high-efficient water saving technique. Effect of partial root-zone irrigation on the photosynthesis, leaf area, dry mass accumulation and water use of sweet corn under two fertilization levels was studied in this paper. The author found that compared with conventional irrigation for whole root zone (CI), under high and fertilization for PRI ,mean transpiration rate reduced 19.01% and 17.50% ,photosynthesis rate increased by 8.88% and 18.34%,leaf water use efficiency (WUE) increased by 34.69% and 43.45%,respectively.With the advance of sweat corn growth stages, the difference of leaf area for different irrigation treatments lessened gradually, mean dry mass reduced 15.14% and 24.38%,mean evapotranspiration (i.e. water use ) reduced 31.28% and 29.58%,while canopy WUE increased 23.48% and 7.40%. The result indicated that partial root-zone irrigation increased more canopy WUE under higher fertilization, so the water saving effect of partial root-zone irrigation should combine with rational fertilization.