Effects Of Different Irrigation Quantity On Corn Growth And Yield Under Mulched Drip Irrigation

The article researched the soil infiltration law of point drip irrigation under different conditions of pressure head which by combining indoor simulation experiments of point drip irrigation with field trials, and a field study was conducted by setting up different irrigation quota(W1-30m3/mu,W2-35 m3/mu,W3-40 m3/mu,W4-45 m3/mu), researching corn growth index(plant hight,stem diameter,leaf area, and dry matter) and root distribution characteristics(root diameter, root weight and percentage) of soil profile and yield index(grain weight per spike, grain number per spike and 100-seed weight), then calculating the water use efficiency and determining appropriate irrigation scheme of drip irrigation under film. The main conclusions are as follows:(1)The power function can be used to describe the relationship between point drip irrigation infiltration maximum horizontal, vertical distance and infiltration time. The shape of two soil moist body under the two head is approximately half a spheroid.(2)From the growth period, plant grew well under irrigation to 40 m3/mu and 45m3/mu of drip irrigation under mulching. Treatments of plant height, stem diameter, leaf area and dry matter volume to grow faster and late slowing with the development of growth period,and treatment of W3,W4 and CK grew well. From the analysis of significant to plant height, stem diameter, leaf area and ground dry weight under different irrigation and period,which could be thought 40-45m3/mu as the reasonalable irrigation amount to drip irrigation under mulching.(3)The average root diameter, root weight and root weight density had the maximum percentage of corn in soil of 0-40 cm while root diameter generally slender and more primary root in soil of 40-100 cm. Irrigation amount had more important effect on corn root diameter of each soil layers and treatments of CK、W4 had more bigger root diameter. Root weight density decreased with the depth of soil increasing from all period, which was significantly higher than all other soil layers in 0-20 cm soil layers and there existed that 0-40 cm soil layers of which had the large percentage. Quadratic fractional function can be used to describe the relationship between root weight density and soil depth among the whole growth period and it is above 0.9 of the correlation coefficient.(4)Soil water storage had greater differences on different growth period and irrigation amount positively correlated with it. Analysis from the whole, the same treatments to the flowering had the largest water consumption while seedling had minimum water consumption. The total water consumption in the order of W4,CK,W3,W2 and W1. Water consumption was positively correlated with the amount of irrigation except treatment of CK.(5)Treatments of C compared with CK in grain weight per spike, grain number and yield were not significantly and which yield reduce less, while the irrigation amount of C reduced than CK 33.33%. W4 had the largest production than increase 20.85% than CK while irrigation amount less 25.00% than CK. It was also found that treatments differences were not significant by the kernel weight and no significant effect on yield. Water use efficiency increased with irrigation increase to drip irrigation under mulching. Water Use Efficiency decreasing order are W4、W3、CK、W3 and W1. CK has the lowest irrigation water use efficiency while W4 is the highest because of the effect of yield index.Thus, a reasonable corn irrigation quota of drip irrigation under mulching is 40-45 cm3/mu in Minqin oasis area and it is not recommended flooding irrigation to cultivate corn.