| It is important to study the regularity of water consumption of crops under different irrigation methods, which has important significance to study the critical period of crop water requirement, to improve water use efficiency, to select the appropriate irrigation method and to develop a reasonable irrigation system.In this experiment, the treatment of regulated deficit at different growth stages under two different irrigation modes of surface irrigation and drip irrigation under mulch film was carried out. Soil moisture as the control variables, monitoring the growth index of Maize in each growth stage.The differences of plant height, stem diameter and leaf area were analyzed by single factor analysis of variance. Yield and water use efficiency of each treatment were analyzed by S-N-K test.Yield and yield related traits were analyzed by means of Pearson correlation test.TDR was used to measure the water content of soil, and the water consumption of Maize under different irrigation methods at different growth stages were calculated by the method of water balance.According to the meteorological data, the reference crop evapotranspiration was calculated by the Penman-Monteith formula, and the influence factors were analyzed.Finally, the crop coefficients in the area were corrected according to the actual water consumption and the reference crop evapotranspiration.The main research results are as follows:(1)Under the condition of full irrigation,the water saving effect of drip irrigation under mulch film was obvious,the water consumption of the whole growth period of the surface irrigation was 588.5mm,and the water consumption of the whole growth period of the drip irrigation under mulch film was 349.79mm.Under the two irrigation methods, the water demand of maize was different in different growth stages,the maximum stage is the pumping stage, followed by the jointing stage, again is the filling stage, the next is the seedling stage, the last is the mature stageAt the beginning stages, the intensity of water consumption is increasing, reaching the maximum at the pumping period and then decreased gradually.(2)The yield has a difference of 540kg/hm2 between surface irrigation and drip irrigation under mulch film under the condition of full irrigation,and the difference was not significant, which showed that drip irrigation under mulch film was suitable for popularization and application in this area.(3)Considering the yield, water consumption, and water use efficiency,the most suitable drought treatments of surface irrigation is in the pumping stage.In this case,water consumption is 491.34mm, yield is 10935kg/hm2, and water use efficiency reached 2.23.The most suitable drought treatments of drip irrigation under mulch film is in the jointing stage.In this case,water consumption is 320.78mm, yield is 10597.5kg/hm2, and water use efficiency reached 3.3.The water use efficiency is less than 3.43 of drought treatment in pumping stage, but the gap is not large, and the yield is higher than its 472.5kg/hm2.(4)The maximum period of reference crop evapotranspiration in this area is jointing stage-filling stage, followed by seeding stage-jointing stage, and the filling stage-mature stage, the minimum is mature stage-harvest.(5)The reference crop evapotranspiration has a significant positive correlation with the solar net radiation, average temperature and sunshine hours,The correlation equations and the correlation coefficients are:y=0.3469x+0.4688, R2=0.8567. y=0.884e0.0567x, R2=0.6043. y=0.0013x3-0.0195x2+0.2148x+1.8072, R2=0.5056;The relationship between reference crop evapotranspiration and wind speed was not significant, and the negative correlation with relative humidity was not significant.(6)Maize in every growing stage:seeding stage-jointing stagejointing stage-filling stage, filling stage-mature stage, mature stage-harvest, the crop coefficients of surface irrigation and drip irrigation under mulch film both showed a single peak trend.Their values are:0.713. 1.964.1.159.0.22,0.478.1.262.0.594.0.034,respectively.Crop coefficients of the whole growing period under two irrigation methods is 1.203 and0.731,respectively. |
PDF Full Text Request