| In order to effectively improve the utilization rate of agricultural water resources and alleviate the water crisis. In this paper, the tomato "seminis 7846" and -"jing 301" were taken as the test materials,and single factor randomized block design of experiment, studied of suitable locations of substrate moisture sensor for real-time controlled irrigation system. Including the composite matrix moisture sensors embedded horizontal distances from the emitter (5 cm, 10 cm, 15 cm) and the vertical distances from the emitter (10 cm, 15 cm) combined after buried, used same water upper and lower limits, the moisture content of the moisture content of different moisture sensors to monitor the water content of the substrate to guide irrigation, was used to analyze the effect of different treatments on growth indicators, photosynthetic indexes, quality, yield, dry matter, irrigation indicators, leaves physical and chemical properties and plant nutrients of tomato. The results are as follows:(1)Effects of site - placement of moisture sensors on greenhouse tomato in summer and autumn:T1 treatment (horizontal distance of 5cm, horizontal distance of 10 cm) deal with the highest light energy capture efficiency of 0.22. T4 treatment (horizontal distance of 10 cm, horizontal distance of 15 cm) had the highest net photosynthetic rate at 11:00, the ratio of sugar to acid was 16.65, and T4 treatment had the best taste. T5 treatment (horizontal distance of 15 cm, horizontal distance of 10 cm) of the highest energy conversion rate of 0.84. T3 treatment (horizontal distance of 10 cm, horizontal distance of 10 cm) had better growth indicators, strong plant growth, more developed root system, a highest root to shoot ratio, the 2nd highest of dry matter. Accumulation of 9:00-17:00 the accumulated values of net photosynthetic rate and transpiration rate were higher, and the fruit Vc content of T3 treatment was 16.21 mg·kg-1, which was significantly higher compared to other treatments. The yield of T3 treatment was 90130.80 kg hm2, the water production efficiency was 18.81 kg·m-3, water production efficiency in T4 treatment was significantly lower than that of T3 treatment, only 16.17 kg·m-3.According to the comprehensive analysis, the matrix moisture sensor 10 cm away from dropping head horizontal distance combined with vertical distance 10 cm apart embedding was appropriate.(2)Effects of site - placement of moisture sensors on greenhouse tomato in spring:T1 treatment (horizontal distance of 5 cm, horizontal distance of 10 cm) had biggest plant nutrient accumulation. T2 treatment (horizontal distance of 5 cm, horizontal distance of 15 cm) had best physical and chemical properties.T4 treatment (horizontal distance of 10 cm, horizontal distance of 15 cm) had highest light energy conversion.T3 treatment (horizontal distance of ]0 cm, horizontal distance of J0 cm)had better growth indicators, more strong root system, a higher root to shoot ratio, the accumulated values of net photosynthetic rate and transpiration rate were the highest at 9:00-17:00, the biggest plant fresh weight. the dry matter accumulation was the highest. But, the fruit Vc content of T3 treatment(horizontal distance of 10 cm, horizontal distance of 10 cm) was 16.21 mg·kg-1, which was significantly higher than that of T2 treatment and T6 treatment(horizontal distance of 15 cm, horizontal distance of 15 cm). The ratio of sugar to acid was 20.02, which was 12.28% and 24.64% higher than that of T1 treatment and T5 treatment respectively. The fruit of T3 treatment had better taste and higher quality.The T3 treatment production up to 59749.2 1kg·hm2, which was significantly better than T2 treatment.And 22.35% and 22.51% higher than T4 treatment and T5 treatment.According to the comprehensive analysis, for greenhouse tomatoes, when using a moisture sensor to monitor the moisture content, the matrix moisture sensor 10 cm away from dropping head horizontal distance combined with vertical distance 10 cm apart embedding was appropriate. |
PDF Full Text Request