Effects of Tempo-spatial Alternate Furrow Irrigation on Farmland Moisture and Yield Formation in Summer Maize

A field research has been conducted for exploring the effect of tempo-spatial alternate furrow irrigation in different growth stage and root zone on summer maize field evaportranspiration,summer maize yield and water use efficiency.Nine irrigation regimes has been designed in summer maize growth period which consists:sufficient water supply in jointing and heading stage(T1N1),sufficient water supply in jointing stage and moderate water deficit in heading stage(T1N2),sufficient water supply in jointing stage and severe water deficit in heading stage(T1N3),moderate water deficit in jointing stage and sufficient water supply in heading stage(T2N1),moderate water deficit in jointing and heading stages(T2N2),moderate water deficit in jointing and severe water deficit in heading stage(T2N3),severe water deficit in jointing stage and adequate water supply in heading stage(T3N1),severe water deficit in jointing stage and moderate water deficit in heading stage(T3N2),severe water deficit in jointing stage and severe water deficit in heading stage(T3N3).The results showed that:soil evaporation in the whole growth period of summer maize showed a pulse-shaped curve,and the percentage of evaporation to evaportranspiration of summer maize decreased from sowing to grain-filling stage and increased from grain-filling stage to maturity.The soil evaporation accounted for 34.89%~52.19% of evaportranspiration in the whole growth period of summer maize and the proportion was decreased along with water deficit intensity.Summer maize yield was showed as the order below:T1N2T2N1T1N3T2N2T2N3T1N1T3N1T3N2T3N3 and yield of T1N2 was significantly higher than others.Water use efficiency(WUE)of T1N2 was the highest among nine treatments(27.08 kg/(ha ·mm))while WUE of T1N1 was the lowest.WUE of T1N2 was higher than T3N1,T3N2,T3N3 and T1N1 for 12.78%,16.9%,19.79% and 26.92%,respectively.WUE of other treatments was declined along with irrigation amount increase.Thus,we conclude that tempo-spatial alternate furrow irrigation regime of sufficient water supply in jointing stage(80% of field capacity)and moderate water deficit in heading stage(65% of field capacity)was favorable for enhancing summer maize yield and water use efficiency in Huanghuaihai Hai summer maize planting zone.