Spray Rates, Droplet Size Make A Difference In Combating Corn Earworm

An ariel study conducted by Agricultural Research Service (ARS) scientists indicates that spray rates and droplet size can make a big difference in insecticide control of corn earworm in sweet corn.

ARS scientist Bradley Fritz, an agricultural engineer at the Southern Plains Agricultural Research Center in College Station, TX, found in an aerial study that spray rates and droplet sizes can make a big difference in whether insecticides that control corn earworms are reaching the target.

Fritz and his ARS colleagues sprayed test plots three times with insecticides approved for organic operations and then collected silks from ears of corn growing on the plots to assess how much spray actually reached the targeted silks. He sprayed some plots with 400-micron droplets and some with 220-micron droplets. The insecticides were mixed with water at label — recommended levels and sprayed at rates of either 5 gallons or 9 gallons per acre.

The results, which are published in the International Agricultural Engineering Journal, indicated that higher spray rates with larger droplets worked best to make sure the insecticide reached the corn silks.

For more information, go to www.ars.usda.gov/is/pr/2010/100412.htm

Source: ARS news release