Sprayers are extensively used for agricultural purpose to prevent crops from pests. The most significant goal in the application of agricultural pesticides is to get uniform distribution of the chemicals throughout the harvest foliage. Under dosing may not give the preferred coverage and control required. Overdosing is expensive as it wastes pesticide and increases the potential for groundwater contamination.
Science and technology always help the human beings to improve its life and the base of life starts from food which derive from agriculture. The invention of a sprayer, pesticides, fertilizers, etc. brings revolution in the agriculture/horticulture sector. Specifically the invention of sprayers, enable farmers to get maximum agricultural output. They are used for garden spraying, liquid fertilizing, weed/pest control & plant leaf polishing. There are many kinds of machine-operated sprayers, the most common of which are low-pressure, high-pressure, air-carrier, and fogger types. Based on the concept of high or low pressure, sprayer provides optimum performance with minimum efforts.
There are various nomenclatures of sprayers available in the market depending upon their specification, pressure capacity and area of use. Some popular names of sprayers are: Power Sprayer, Knapsack power sprayer, battery operated sprayer, Misting Pumps. Some sprayers are also designed for domestic uses as Car Washers and Domestic Washers. These are widely used in car garages, big farm houses, hotels for cleaning of lawns, staircases.
The technique used for spray crops is very important to get good coverage. It should be developed to fit the type of equipment that is to be used. With a hand-held gun, a sweeping motion over the foliage will allow the spray material to penetrate and get to the underside of the leaves.
With fixed-fan type units, an airflow pattern needs to be established so that all the plant canopy receives the pesticide; location of the unit contributes to good air flow. Using an air circulation system, enhance the movement and distribution of the fog and mist particles.
The fans should continue to operate for 30-60 minutes after the spraying operation is done.
Observation should be made to ensure that the sprayer is operating properly and that adequate coverage is obtained.
One should keep a log of the spraying operations and the results that were obtained for optimized outcomes. This should include the date, time and location of application; crop and pest; pesticide used; tank mix; and an evaluation of the results obtained.
Adjustments should be made in subsequent applications to try to improve the results.
Proper selection, calibration & operation of spray equipment is significant in achieving optimal pest control, as well as in meeting environment & safety necessities.
One of the famous sprayer application methods is controlled droplet application (CDA)
CDA technology produces uniform droplets using a rotary spray nozzle. In operation, the rotary nozzle accumulates spray solution at the bottom of a spinning cup. The centrifugal force of the cup creates spray droplets, which are forced up multiple grooves on the inside of the cup. From there, the solution reaches the top of the rotary nozzle, and droplets are projected in a circular pattern up to a six-foot (1.8-m) diameter. Droplet diameter is determined by the speed of the cup. CDA is seen as advantageous as less water is required per acre of spray.