| The key to the development of modern agriculture depends on water saving. Water saving irrigation is not only the technological problem, but also the basic problem that relates to the development of modern agriculture. It also concretely embodies principles of the reality of the sustainable development strategy of using water resources and management from extensive mode to intensive mode. With the quick development of agriculture information technology, many information technologies, such as the sensor and automation technology, had been widely applied in the field of the precise agriculture. These technologies in practice provide a feasible way for monitoring soil water in reality. We should make a better irrigation schedule on the basis of the agriculture technology, besides real-time monitor of soil water. The cotton irrigation is impacted not only by the plant and soil in the cotton fields, but also by the weather factor and so on. Therefore, the aim of water saving can be really realized by studying on irrigation schedule in the future.On the basis of the research on the theory of introducing the cotton irrigation schedule and the information agriculture technologies that relate to real-time monitor of soil water, real-time monitor of soil water information in the partial area has been realized by the use of TS-2 mode silicon piezoresistive sensor. At the same time, according to the irrigation experiment, we have made a summary of the lowest soil water potential in the stages of cotton growth and the irrigation schedule on the variety of hybridization cotton——Biao za A1.The main results are recounted as follows:1) Use the TS-2 mode silicon piezoresistive sensor to real-time measure soil water potential in the different depth range of 0～20cm or 20～40cm in the soil; Send the data signal to the computer by four-channel water potential transmitter. After the data signal is accepted by the computer, dynamic monitor of soil water potential will be successfully realized by the monitor system software. According to the irrigation situation in the northern of Xinjiang province in china at present, piezoresistive sensors are arranged in the depth of 20cm or 40cm in the soil. At the same time, determine soil moisture characteristic curve equations of the difference soil layers. The farmers can judge soil relative water content according to dynamic soil water potential in the different soil layers by soil moisture characteristic curve equations, so that they can directly master soil water information.2) According to the relation equations between soil water potential in the different layers and predawn leaf water potential of the top fourth leaf of cotton, on the basis of the research on the critical predawn leaf water potential value of requirement water during the cotton growth stages, conclusions are made as follows: In the pre-flowering stage, flowering and boll-setting stage and open boll stage of the cotton growth, the lowest soil water potential value in the 0～20cm soil layer is -34.9KPa, -40.2KPa and -45.0KPa respectively; the lowest soil water potential value in the 20～40cm soil layer is -43.3KPa,-49.1KPa and -54.0KPa respectively.3) When the yield of ginned cotton is the highest, the quota of irrigation amount should be 447.47mm. Computing water saving economy according to water price of 0.15 CNY/m3 and the ginned cotton price of 14.01 CNY/Kg, the irrigation upper limit is 447.16mm. According to the cost of planted area, the irrigation lower limit is 447.47mm; According to the cost of irrigation water, currently, regarding the water price of 0.15 CNY/m3 and the plant cotton cost of 12443.7 CNY/hm2, the irrigation lower limit is 445.88mm. When water use efficient is the highest, the amount of cotton irrigation is 254.49mm.4) When the yield of the ginned cotton is the highest, the total amount of evapotranspiration is 601.23mm; when water use efficiency is the highest, the total amount of evapotranspiration is 537.50mm. The reasonable total amount of evapotranspiration under membrane drip irrigation should be change in the range from 537.50mm to 601.23mm during the whole cotton growth period.
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