The fall season can be tricky because of staggered plantings, continued warm temperatures that encourage disease, hungry insects leaving harborage in summer weeds to attack young tomato plants, and rapidly changing weather conditions with winds that can blow in unwanted pests. Planning ahead to manage expected pest issues before they hurt crop establishment is the optimal offensive strategy.
Whitefly Watch in Tomatoes
Previously light whitefly populations can catch growers off guard. Tomato transplants should be scouted for silverleaf whitefly signs, especially around areas that weren’t able to be completely cleaned up at the end of the season. Adult whiteflies are the main insect-control concern in the early season, since they can transmit pathogens. Later in the season, nymphs can cause problems by damaging leaves, causing irregular ripening and reducing interior fruit quality.
Growers who detect whitefly populations near treatment threshold should take action to limit feeding time and reduce the risk of transmission of diseases such as tomato yellow leaf curl virus. Controlling whitefly populations also promotes early crop vigor, which supports an abundant harvest.
These programs for tomato insect control promote fruit quality and uniformity:
- DuPont™ Verimark® insect control powered by Cyazypyr® in a tray drench or transplant water treatment (13.5 ounces per acre) improves crop establishment by reducing virus incidence when used as part of a virus management program. Verimark® should be used along with a whitefly adulticide as needed and followed with a neonicotinoid three to five weeks later. To manage insect resistance when Verimark® is used at planting, an IRAC group 28 insecticide should not be used for approximately 60 days after application.
- If additional treatments are needed to manage insect pests at the end of the season, a foliar application of DuPont™ Coragen® insect control powered by Rynaxypyr® or DuPont™ Exirel® insect control powered by Cyazypyr® should be used, following label directions.
- If growers have no concerns about the performance they are getting with their current virus management programs, they may want to stick with Coragen® for whitefly nymph suppression along with an effective adult whitefly control program. The recommendation is to start the season with a neonicotinoid, followed by two applications of Coragen® five and seven weeks later.
More than one at-plant or two drip chemigation or soil injection applications of Verimark® per crop should not be used. Verimark®, Exirel® and Coragen® are Group 28 insecticides, so they should be alternated with other modes of action to help manage and avoid resistance development.
Comprehensive Management Steps
Other cultural practices that help reduce disease losses in tomatoes are listed in this set of reminders from theUniversity of Florida IFAS Extension:
- Use plastic mulch and staking to control fruit rots and reduce losses.
- Plant disease-free transplants or certified pathogen-free seed.
- Get rid of volunteer plants.
- Rotate crops.
- Increase soil pH.
- Set planting dates based on weather-related disease risk.
- Avoid extra thinning, pruning and other handling.
- Skip overhead irrigation.
- Eliminate weeds around fields in season and off-season.
The information provided on this website is for reference only. Always refer to the product labels for complete details and directions for use.
DuPont™ Coragen®, Exirel® and Verimark® are not available in all states. See your local DuPont sales representative or retailer for details on availability.