Common spray methods

Commonly used pesticide application methods include spraying, dusting, spreading, pouring, dripping, injection, smearing, dipping, seed dressing, poison bait, fumigation, etc. The focus here is on the spray method. The spray method is a relatively common application method, that is, a certain amount of pesticide and an appropriate amount of water are mixed into a liquid medicine, and the liquid medicine is sprayed into mist droplets with a spray device. This method is suitable for pesticide formulations such as emulsifiable concentrate, water, wettable powder, soluble powder and colloidal suspension.

It can be used for stem and leaf treatment as well as soil treatment.

1. Commonly used spray methods

According to the amount of liquid sprayed per mu (667 square meters), spray methods are often divided into several categories such as high-volume spray, medium-volume spray, low-volume spray, very low-volume spray and ultra-low-volume spray.

1. High volume spray

High-volume spray, also known as coarse spray, mostly uses 16-type backpack type manual sprayer and 36-type motorized sprayer for application. The spraying liquid volume per mu (667 square meters) exceeds 40 liters, mostly 50~75 liters, and the pesticide is diluted with water. , the liquid concentration is less than 1000

mg/kg, the median diameter of droplets is 400~1000 microns, and it is a targeted spray method. High-volume spray is suitable for controlling plant base pests and weeds in agricultural areas with abundant water sources, and for soil treatment to control weeds. Loss of more, resulting in soil and water pollution.

2. Medium volume spray

Also known as constant spray, it is sprayed with the Gongnong 16 backpack type manual sprayer and the 552-C shoulder-mounted manual sprayer. The nozzle diameter of the nozzle is 1.3~1.6 mm, and the liquid is diluted with water. The concentration is 1000 mg/kg Above, the spray volume per mu (667 square meters) is 12.5~50 liters, and the median diameter of the droplets is 250~400 microns, which is also a targeted spray. Medium volume spray is also used in watery areas, and the utilization rate of pesticides is higher than that of high volume spray. Low volume spray, also known as fine spray or mist. Use Gongnong 16 type and 552-C type sprayers, and the nozzles equipped with 0.7~1.0 mm nozzle aperture are fine sprays. Using the Dongfanghong 18 type motorized sprayer to spray the liquid medicine into mist with high-speed airflow is often called mist. The low-volume spray is diluted with water, the concentration of the liquid is 0.8~3%, the amount of liquid sprayed per mu (667 square meters) is 2.5~12.5 liters, and the median diameter of the droplets is 150~250 microns. It is a targeted spray and The spray method combined with drift spray can avoid the bouncing and rolling phenomenon caused by large droplets, and the droplets have good dispersion among plants, which can achieve the effective droplet coverage density standard heat for controlling diseases and insects. And through the plant's systemic absorption, infiltration, and plant's own functions such as respiration, transpiration, and physiological water spitting, the pesticides play a role in redistribution. Low-volume spray is suitable for preventing and controlling foliar pests and diseases of crops, and has the advantages of good control effect and saving pesticides, but it is not suitable for chemical weeding. Due to the high concentration of pesticides used, this spray method cannot be used for highly toxic pesticides.

3. Very low volume spray

Also known as micro spray, it uses Dongfanghong 18 type motorized sprayer, with water or oil as the carrier, the pesticide concentration is 3~10%, the spray volume per mu (667 square meters) is 0.5~2.5 liters, and the droplet diameter is 80 ~150 microns, is a drift-cumulative spray. It is suitable for large-scale control of diseases and insect pests in areas with little water, but is not suitable for chemical weeding in farmland. Micro-spray has the advantages of being resistant to rain erosion and long-lasting, but it is greatly affected by climate, and the loss of droplet drift is large.

4. Ultra-low volume spray Ultra-low volume spray

The micro-spray is called Dongfanghong 18 type motorized sprayer plus ultra-low-capacity nozzle spray, with oil or water as the carrier, the pesticide concentration reaches 10~60%, and the spray volume per mu (667 square meters) is 0.15~0.5 liters , the median diameter of the droplets is 15~75 microns, and it is also a drift accumulation spray. It is suitable for areas with little water to prevent and control outbreaks of pests and diseases, and cannot be used for chemical weeding in farmland. It has the advantages of high work efficiency, saving pesticides, timely prevention and control, and no water use, but the operation technology is strict, the mist droplets are greatly affected by the airflow, and improper application will cause phytotoxicity.