NEWS200208AGAIRUPDATEMAGAZINE

Electrostatic spay technology has been shown to improve significantly spray deposition on the top and bottom surfaces of leaves, reduce drift and run-off, reduce the quantity of water needed, and in some cases reduce the pesticide required to do the job. Electrostatic spray technology has been used successfully for years in improving insect control and defoliation in cotton. Dr. J.B. Carlton and associates with the USDA-ARS in College Station, TX, developed the technology which is now being used effectively by Speck Thornton, owner of Independent Dusting Service, Inc. in El Campo to apply herbicides, insecticides and defoliants to over 100,000 acres of cotton and rice.

How does it work? An electrode surrounds each nozzle and induces a static electric charge to the spray droplets as they emerge from the nozzle. The electrostatically charged spray droplets are attracted to the surfaces of leaf tissue. This results is much improved, more uniform coverage of the foliage. Spray volumes can be reduced from the conventional 10-gallon per acre or 5-gallon per acre rates to as low as 1- or 2-gallons per acre with the electrostatic system. On June 6, I participated in a field demonstration in Wharton county where a spray dye was applied aerially to a rice crop at about the 2- to 4- inch particle stage with a conventional spray rig at 10 gallons and 5 gallons per acre, and with the electrostatic system at only one gallon per acre. I was impressed by the apparent improved, more uniform coverage of the rice foliage on both surfaces of the leaves with the electrostatic spray system. It would be interesting to see if this improved coverage resulted in improved sheath blight control. It should be at least as effective as the conventional 10-gallon application with similar quantity of fungicide.

Even if disease control is similar between the two application methods, savings in the cost of application can be passed on to the farmer, since application efficiency is much improved and the pilot can spray many more acres with less re-loading. This new technology could be very useful in rice production.