The main conditions for the occurrence of pests and diseases in greenhouses are temperature, humidity, source of bacteria, disease resistance of varieties, and cultivation measures. The ecological control of greenhouse vegetables is through the control of the above ecological factors, so as to reduce the amount of chemical pesticides and eliminate pollution residues. As a result, people eat more safely and the pests are controlled. The ecological control measures for Solanaceae, melons, gray mold, and diseases are briefly described as follows:
1. The regulation of temperature conditions. The low temperature in the greenhouse is the main reason for the occurrence of eggplant and melon gray mold. In practice, high-twin double-film cover is used, and a ventilation window is left every 3 meters in the booth. The grass curtains are opened early in the morning and the curtains are closed in the afternoon. The temperature exceeds 30 °C in a timely manner. When the average temperature in winter and spring is lower than 15°C, close the vents to achieve better insulation effect.
2. Regulation of light conditions. Insufficient light temperature is difficult to guarantee, aging of the film, poor light transmission, and dust droplets all affect the light. Tests determined that the use of non-drip film can increase light about 20%. When building a shed, it is required that the shed be shifted to about 10 degrees to the west in order to increase the temperature of the shed.
3. Regulation of moisture conditions. Excessive humidity in the shed is also an important factor in causing disease. For this reason, when the relative humidity in the morning shed exceeds 90%, the air should be released 20 to 30 minutes in a timely manner. Practice has proved that with double membrane coverage, watering under membrane, timely release of air, the relative humidity in the shed at 3 pm is 62%; the double membrane coverage, 58% of the membrane under drip irrigation, the relative humidity in the control booth is 87%. .
4. Regulation of gas conditions. The carbon dioxide concentration in greenhouses is too low, which affects the photosynthesis of vegetables, weak growth potential, and reduces disease resistance. For some of the sheds with higher management levels, organic fertilizers are required to increase carbon dioxide, or after seeing fruits, the addition of carbon dioxide gas fertilizer from the uncovering of the straw curtain to the noon will significantly enhance the growth of fruits and enhance Disease resistance.
We are the one of three leading factory in China, specialized in manufacturing laser distance module since 2004. Bilateral laser distance measurer is one of mutifunctional laser distance device. JRT multifunctional laser measuring device functions include area,distance,length,volume,continuous measurement,addition and subtraction, measuring unit: ft/m/inch. More functions can be customerized. And the laser measuring meter have distance 30/40/60/80/100/150m for chosing. This bilateral degin is our 40m middle laser distance transducer 703A laser measuring meter.
OEM service:
* usb chargable
* voice
* IP54 rating
* Colorful case
Laser Range Finder Measurer,80M Laser Distance Meter,Distance Meter 80M,Laser Distance Meters
Chengdu JRT Meter Technology Co., Ltd , https://www.rangesensors.com