Study On Automatic Control Technology For Irrigation Of Cucumber In Greenhouse Based On The Sap Flow

This paper pointed out many disadvantages of experience-based artificially irrigation which is applied in the greenhouses, and study automatic real-time control technology for irrigation in intelligent greenhouse, based on the experience with cucumber. Main works as follows:1. Based on the field experiment, the author analysed the varying character of cucumber transpiration rate with different temperature, humidity and light, and the water potential of the cucumber. The author qualitatively analysed the SPAC with the water potential. At last author established the cucumber transpiration rate diagnose model on the basis of the varying regular of the sap flow with different soil moisture handle. The author analysed the varying character of the sap flow, investigated the positive correlation between the transpiration and the slap flow.2. With collecting the environment factors inside of the greenhouse during given cultivation stage and calculating the irrigation amount of the cucumber, the author established the relational function between the temperature, humidity, light and the irrigation amount with the method of regress analysis.3. Based on the testing data, the author established the model base, database and rules during decision. The system is programmed by Visual basic 6.0. It has a friendly interface. For example, the system can give the theory value of irrigation when the temperature, humidity and light are inputted.