Reduction in cotton, peanuts and tobacco acreage in the Southeast in recent years is the primary impetus for increased vegetable production in the region.
One drawback to production has been the high cost and varying success of insect management.
Speaking at the recent South Carolina-Georgia Fruit and Vegetable Growers Meeting, University of Georgia Entomologist Stormy Sparks told growers that 2009 will likely continue to be a challenge for insect management, but that a number of new insecticides will make that chore more manageable.
Sparks stressed that he could not include all the insecticides labeled for use on vegetables, but listed a number of new products that could help vegetable growers in the Southeast make better insect management decisions.
Belay is a new insecticide from Valent that looks particularly good for wireworm control on potatoes. It has a long residual, giving growers more flexibility in managing wireworms and other worm pests of potatoes, Sparks notes. Belay's active ingredient, clothianidin, has longer residual activity and less water solubility than others in the same chemical class, he adds.
Belay’s new potato seed piece label in 2009 joins the soil and foliar uses launched in 2008. Belay's active ingredient, clothianidin, has longer residual activity and less water solubility than others in the same chemical class, often providing 7-14 days longer control of insect pests than some commonly used insecticides.
Belay can be mixed with most fungicides used on vegetables and has good seed safety when used in either seed piece treatment or in-furrow treatments. Seed piece treatment rates are .4-.6 ounces per hundredweight, based on seeding rate of 2,000 pounds per acre. Soil applied rates are 9.6 to 12 ounces per acre and foliar rates are 2-3 ounces per acre.
Endigo is another materal that looks good on Colorado potato beetles, aphids and leafhoppers. Its two active ingredients make it a little different from some other long-time potato insecticides, Sparks says.
Endigo is an enhanced product with two modes of action which combine knockdown and residual activity for sucking and chewing pests.
Endigo has good residual activity and is also an excellent rotational product. Vegetable growers have seen a number of good products fall prey to resistance problems. Like several of the newer vegetable insecticides, Endigo provides an excellent rotational product to organophosphates and carbamates, Sparks notes.
Zeal is a new acaracide that provides good control of two-spotted spider mites. Sparks reminds growers that this material has no activity on adult mites.
Zeal has up to a 30-day residual, but coverage is essential. Its best use, the Georgia specialist says, is probably as a one-time per season application that helps reduce the risk of resistance.
Zeal, which is also known as Secure, comes from a new class of chemistry, diphenyloxazoline. It acts primarily as an ovicide, but has some molt-inhibiting activity against immature mites.
Requiem is a safe green-type product used to control white flies, aphids, thrips and spider mites. Sparks says this new product may have its biggest impact on reducing diseases that are vectored by early season insects on vegetables.
It is a contact material, so good ground coverage is a must. Requiem is very safe, with only a four-day re-entry requirement.
Watermelon growers in particular may want to take a look at this material, Sparks says. It has looked good in trials in reducing vine decline in watermelons, in addition to helping with management of diseases spread by insects.
In addition to its strong fit into IPM programs, Requiem possesses a unique mode of action, unlike any other insecticide on the market, making it ideal for managing resistance, a problem facing growers throughout the United States
Movento has dual systemic activity which moves upward and downward in the plant. Growers must add a surfactant when using this material, Sparks stresses.
It has shown excellent control in tests, according to Sparks. In the first and second instar nymphs in whiteflies, for example, Movento provided 90 percent control. When white flies matured to the third and fourth instars, control dropped by about 50 percent.
Movento utilizes a unique new active ingredient with a new mode of action, Lipid Biosynthesis Inhibitor (LBI), from a newer chemical class, the Tetramic acids. It is active by ingestion against immature insects feeding on treated plants
Synapse is labeled for use on brassica, cucurbits, fruiting and leafy vegetable crops. It has shown great control of caterpillars in tests. In existing infestations of caterpillars, Synapse can halt feeding minutes after it is ingested. In today’s high value vegetable crops, minimizing insect feeding damage can be a critical factor.
In addition to fast knockdown, Synapse has good residual activity. It is a highly targeted pesticide and has minimum effect on beneficials, making it a good choice in IPM programs. It has a slightly different mode of action, which also makes it a good fit in resistance management programs
Coragen is widely labeled for use on a number of vegetable crops. It has shown excellent control of caterpillars. Whitefly control is highly dependent on the use of an adjuvant, according to Sparks.
This material is not a rescue insecticide. In general, if you see damage on the plant, it’s too late to use this material.
Perhaps the best use of Coragen will be on tomatoes. The tomato fruitworm, also known as corn earworm and cotton bollworm, is a primary pest of tomatoes. Many insecticide applications are often needed to obtain adequate, continuous control of this lepidopteran pest. To date, the insecticides of choice have been primarily pyrethroids.
Researchers at Virginia Tech’s Eastern Shore Agricultural Research and Education Center in Painter, Va, tested Coragen along with a number of standard tomato insecticides.
A high rate of Coragen applied once or applied twice, the low rate of Coragen applied three times and a foliar application of Mustang Max plus Spintor provided the best control with no significant differences among them.
On the second harvest, all treatments except the low rate of Coragen applied once had significantly less fruit damage than the untreated check plots.
While the arsenal for insect control in vegetables is growing, there is an ongoing pressure to rotate these materials to avoid resistance. In 2009 growers will have several options for both better control and better resistance management.