Effect of different irrigation and nitrogen fertilizer on spring maize growth,yield and water use

A field experiment was conducted to study the effect of irrigation at different growth stages and nitrogen fertilizer on spring maize growth,yield and water use efficiency.The experiment included eight irrigation treatments: irrigation at the whole growth period(CK),no irrigation at seedling stage(I1),no irrigation at jointing stage(I2),no irrigation at heading stage(I3),no irrigation at filling stage(I4),no irrigation at seedling stage and heading stage(I13),no irrigation at seedling stage and filling stage(I14),no irrigation at jointing stage and heading stage(I24) and four nitrogen levels: non-nitrogen(ZN),low nitrogen(LN,60 kg N/hm2),medium nitrogen(HN,120 kg N/hm2),high nitrogen(HN,180 kg N/hm2).The results showed that no irrigation in any of the growth stages reduced spring maize plant height,leaf area and grain yield.Irrigation treatment at seedling stage had significant effect on plant height.Nitrogen fertilizer treatment at the whole growth stage had significant effect on the plant height.But water and nitrogen interaction at seedling stage had no significant effect on the plant height.Compared with the treatment of irrigation at whole growth stages(CK),the treatments I2 and I24 had the greatest impact on plant height,reduced it by 11.42% at most.Irrigation treatments,nitrogen fertilizer treatments and water and nitrogen interaction at the whole growth stage had significant effect on leaf area.However,the effect of no irrigation treatment of the two growth stages on leaf area is greater than no irrigation treatment of single growth stage.The effect of no irrigation treatment of single growth stage on leaf area was I4I3I1I2.The effect of no irrigation treatment of the two growth stages at the nitrogen level ZN,LN was I13I14I24,but at the nitrogen level MN,HN was I24=I14I13.Irrigation treatments and nitrogen fertilizer treatments both had significant effect on 1000-grain weight,grain weight per spike and grain yield.Compared with the CK,I3 and I13 had the greatest impact on grain yield,and the largest drop was 28.76%.I1 and I4 had high yield and water use efficiency at high level of nitrogen fertilizer treatment.