Extension Report

Baldwin County Extension Office

302A Byrne Street

Bay Minette, AL  36507

Telephone (251) 937-7176 or

928-0860/943-5611 ext. 2222

FAX (251) 937-7285

Dr. Ayanava Majumdar

Extension Entomologist & State Sustainable Agriculture Coordinator

Auburn University

January 12, 2010

New Insect Control Options for Profitable Vegetable Production

Happy New Year to readers! Commercial vegetables are produced on about 5000 acres in Alabama and  are valued over $17 million dollars (2008 Federal data). Alabama producers grow 34 vegetables and the state ranks twelfth in tomato production nationally. Insects are a major pest of vegetables and cost-effective insect management can be best achieved by adopting integrated pest management (IPM) tactics and developing an IPM plan specific to your farm. The first step in an IPM plan should be to scout the crops at weekly intervals after transplanting in order to detect early insect outbreaks. Remember, insect control is easier when caterpillars are at a small stage and feeding on the upper foliage. Older caterpillars are not only difficult to kill due to their size but pest could hide inside the crop canopy where insecticides cannot reach. Growers should utilize IPM insect pheromone traps for monitoring pests throughout the season; modern pheromone traps are cost effective, durable and available for monitoring many insect species. ACES conducted an insect survey in 2009 using traps and project results can be found at www.aces.edu/go/85.

The second step in IPM plan is to correctly identify the insect pest because incorrect identification can lead to wrong treatment decisions (visit  www.aces.edu/go/87 or refer to Extension publications for pest identification). The third step in IPM plan is to determine the need of chemical intervention using decision-making tools like economic thresholds. If you primarily depend on synthetic insecticides, then you may be interested in knowing a bit more about the new generation insecticides for commercial vegetable production. Mention of names does not mean endorsement of those products.

Insecticide  mode of action: Typically, conventional pyrethroid and organophosphorus insecticides are nerve poisons that have to come in contact with insects to be effective. These insecticides have short molecular structure, wide-spectrum of activity against pests, and cause nontarget effects. In contrast, some of the  new products are long chain molecules with high target specificity and safety to beneficial arthropods. These new products are activated by enzyme systems in insects after absorption through the skin or ingestion.

New insecticidal products: Spinetoram (Radiant 1SC, a new form of spinosyn by Dow AgroSciences) has excellent activity against caterpillars such as thrips, corn earwom, European corn borer, imported cabbageworm, diamondback moth, etc. Spinosyn insecticides have short pre-harvest interval (1 to 3 days) and can be applied safely on many vegetables, but there are some insecticide resistance concerns. Spirotetramat (Movento 2SC by Bayer CropScience) can be applied in the form of foliar spray and chemigation. It has excellent activity against sucking pests like aphids and whiteflies. Spiromesifen (Oberon 2SC by Bayer CropScience) belongs to the same family of products as Spirotetramat and has similar mode of action (i.e., metabolic disruption). Oberon is registered in Alabama for use against mites and has some activity against whiteflies. Flubendiamide (Synapse 24WG or Belt SC by Bayer CropScience) is a feeding inhibitor. It can be applied as foliar spray or chemigation and is very effective against corn earworm, European corn borer, fall and beet armyworms, loopers, and other caterpillars. Rynaxypyr (Coragen 1.67SC by DuPont and other products) is a new type of nerve poison which impacts insect muscles causing convulsions and death. Rynaxypyr acts rapidly in insects and has very good activity against the Colorado potato beetle and caterpillars in young stages. It appears to be safe for parasitoids, predators, and pollinators based on the label information. Pymetrozine (Fulfill 50 WDG by Syngenta) is a selective feeding inhibitor active against aphids infesting a variety of vegetables and row crops. It can be applied with ground equipment and chemigation at low rates. Methoxyfenozide (Intrepid 2F by Dow AgroSciences) is an insect growth regulator that provides excellent control of armyworm and cabbageworm. This insecticide may be applied at low rates for controlling small caterpillars. Emamectin benzoate (Proclaim 5WDG by Syngenta) is an avermectin product that has both contact and stomach activity against beet armyworm, imported cabbageworm, and the like. Timing of applications and appropriate dosage is very critical for some new products (e.g., the antifeedants with target specificity). Refer to a copy of the 2010 Southeastern Vegetable Crop Handbook for more details at aces.edu/dept/com-veg.

Commercial vegetable producers now have a wide array of control options that, unfortunately, homeowners and gardeners do not have. New products may or may not be available at the local Co-op; so contact a pesticide dealer or an industry representative about product availability and cost. Producers should check insecticide registrations, application rates, and safety issues before using them. The IPM insect monitoring project mentioned earlier is going to continue in 2010 and growers can receive results in many ways. Information from IPM entomology projects is sent out weekly in different forms to reach large audience; this approach is called the IPM-CORE, short for “IPM Communication Resource” system which was established in 2009. By signing up for IPM-CORE , vegetable as well as row-crop producers can get weekly Pest Alerts via email (send your email request to bugdoctor@auburn.edu to register today) or you can visit www.aces.edu/go/85 to download reports. Pest Alerts also can be sent to growers via phone text service (email your phone number to bugdoctor@auburn.edu). Alternatively, growers can call the Alabama IPM hotline at 1-800-446-0375 for listening to 2-minute updates on insect pest activity reports.

Email address: azm0024@auburn.edu

Phone: 937-7176 or 943-5611, ext. 2222

The Alabama Cooperative Extension System (Alabama A&M and Auburn Universities) in cooperation with the U.S. Department of Agriculture is an equal opportunity educator and employer.