Research Of Soil Moisture Sensors Reasonable Buried Location In Real-time Control Irrigation System Of Greenhouse Cucumbers

Based on real-time control of irrigation system, the question of the soil moisture sensor embedded reasonable position for greenhouse cucumber. Use cucumber’bomei 626’as test variety. Six treatments of sensors were set according to combining with the horizontal distance of sensor from the water dropper and vertical buried depth. Each treatment using the same irrigation water limit, according to the sensor measures the soil moisture guidance control irrigation, the growth indexes, photosynthetic indexes, irrigation indexes, yield and quality indicators were analyzed under different treatments of summer and spring cucumber, determine the reasonable laying position of soil moisture sensor. The results are as follows:1. The reasonable buried position of soil moisture sensor on real-time control irrigation system of planting the summer cucumber, the research result shows:(1) The cucumber morphological index of plant height, stem diameter, internode length and leaf area is superior to other treatments and the cucumber root flourish, vigorous growth of stem and leaf, plant growing well, when the sensor buried in the horizontal distance of 15 cm or 10 cm from the water dropper, the vertical buried depth of 10 cm from the water dropper.(2) When the horizontal distance of 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper, cucumber net photosynthetic rate cumulative value, quality and yield are higher than other treatments, meanwhile the irrigation amount is less than others. The irrigation water production rate is 33.56 kg·m-3 highest than other treatments.(3) When the sensor buried in the horizontal distance of 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper, the soil moisture have a greater coefficient of variation, it can sensitive indicator water dynamics and have high stability. This location is suitable for buried soil moisture sensor.2. The reasonable buried position of soil moisture sensor on real-time control irrigation system of planting the spring grafted cucumber, the research result shows:(1) The grafted cucumber plants stem diameter and leaf area are better than others, and the underground root system flourish, stems and leaves grow strong, plant morphology index is better than other treatments, when the sensor buried in the horizontal distance of 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper.(2) When the sensor buried in the horizontal distance of 15 cm or 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper, grafted cucumber chlorophyll content and net photosynthetic rate is higher than others, and total root length of cucumber, total root surface area and root total volume are significantly higher than other treatments. When the sensor buried in the horizontal distance of 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper, the cucumber yield is higher and less irrigation amount, the irrigation water production rate is 38.34 kg·m-3, and the soluble sugar content, soluble solids content and the highest ratio of sugar to acid are the highest, the organic acids content is the lowest, cucumber quality is the best.(3) Linear correlation analysis showed that the sensor buried in the horizontal distance of 10 cm from the water dropper, the vertical buried depth of 10 cm from the water dropper has the highest linear correlation with other treatments, it can represent the soil moisture content values of other treatments.Based on the result of the spring and summer cucumber showed that, when the sensor buried in the horizontal distance of 10 cm from the water dropper and the vertical buried depth of 10 cm from the water dropper, can direct irrigation, not only saving water, but also have high yield.