| Precision irrigation is currently extensive research to achieve water-saving purposes. One of advantage to measure soil moisture by crop water requirement of automatic irrigation is expected to be the most effective water-saving. This thesis studied the biological characteristics and the water use efficiency of winter wheat under irrigation based on different depths soil moisture sensor; and field experiments studied soil water movement, soil surface evaporation and physiological maturity of the grape plant and other observations under irrigation based on measurements ofsoil moisture sensor. Main conclusions drawn are as follows:(1) In the laboratory test, the irrigation amount of C10 (sensor undersurface 10 cm) are less than C20 as well as the C5, close to the CK treatment, the volume of soil water content from the dynamic point of view, under the C10 treatment 5cm and 10cm depth of soil moisture content did not appear not below the wilting points, plant growth was not under water stress. At the same time 20cm probe showed, 20cm depth of soil moisture were lower than the wilting moisture. From the biological characteristics of wheat, the best controlling sensor should be buried under 10cm, because plant height, coverage, aboveground biomass, and water use efficiency were highest during the experimental period.(2) In the field test, there were good correlation between 10cm and 20cm of soil moisture under different treatments: good correlations among four soil water content under SF20 treatment,which means amount of sensors could be reduced. 10cm depth senor can be ignored since there were very good correlation between 10 cm and 20 cm sensors.; SF40 in the root depth of the soil under the four volumetric water content there was a correlation between, but compared to SF20, the monitoring of the depth of the adjacent the correlation coefficient between not high, especially between 40cm and 80cm depth of the correlation coefficient is only 0.461, far below the SF20 treatment depth of 40cm and 80cm between the correlation coefficient 0.890. In order to observe this root zoon, it is recommended to address the root 60cm of soil moisture sensors under the SF40 treatment. There were good correlations amongthree soil moisture sensors planted area, while the root of 20cm and 20cm deep ditch volumetric water content is higher than the correlation coefficient between the root of 20cm and 20cm under the ridge of the correlation coefficient. SF40 horizontal position on each soil moisture correlation between the volumes of water content is similar with the SF20. From the perspective of reducing costs, soil moisture sensors can be reduced under the irrigation.(3) In SF20 and SF40 treatments,soil volumetric water contents of 0-10 cm affected significantly by irrigation. 80cm depth of soil volumetric water content in SF20 decreased during the growing period, which indicated water could not infiltrate to 80 cm; 80cm depth of soil volumetric water content in SF40 remained stable, which indicated that water could infiltrate to 80 cm under controlling irrigation using 40 cm sensor placement.(4) In the field test, different depth of soil under control irrigation treatment intensity of surface evaporation expressed as CK> SF20> SF40. Different treatments under the grape LAI and cumulative evaporation between soil surfaces showed an inverse trend.. Because of the longer irrigation period, water can infiltrate to deep soil which led to lower soil evaporation compared to CK, which had more water in soil surface.(5) Under field climate and soil conditions, the WUE of SF40 was 6.04 kg/m3, SF20 was 5.37kg/m3, CK was 4.58 kg/m3. SF40's higher than the other two treatments, SF20 of the yields slightly higher than the CK, the three deal with the output of SF40 up to 60.8 t/hm2, SF20 for 51.6t/hm2, CK is 49.5 t/hm2. Blades: SF40> SF20≈CK; leaf area: SF40> SF20> CK during the hole growth period. Net photosynthetic rate of the size of SF40> SF20> CK. SF40 above indicators is higher than 20cm depth control processing and control, while the sugar content is slightly lower when compared with the other two dealing with, but close to 20%; three processing sugar SF20 of 21.6%, SF40, 19.5 %, CK 20.5%. SF20 and SF40 are better than those in CK. Sensor from depth of 40cm was the best in controlling grape irrigation in the field.
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