Issue
Select issue to view:
Search
Other Options
View article as PDF
(right-click on above link to save as a file).
Download free viewer...
View all articles in the June, 1997 issue
Cover Photo Gallery
View our covers back to 1998
Order back issues
Newsfeed
View headlines from our latest issue with your news reader:
Mite Management
When hot, dry weather in the Northeast set off a mite explosion this season, some apple growers in Virginia, New Jersey and Delaware wished they had a new weapon to use against the mites.
By late August, they received that weapon. It was Pyramite, a new broadspectrum apple miticide/insecticide from BASF Agricultural Products, Research Triangle Park, N.C. Pyramite received Section 18 emergency use registration from the EPA on Aug. 23. The Section 18 expired Sept. 30.
An application for full registration of Pyramite was submitted to the EPA in December 1995 and remains pending. Usage is being sought for all principal apple varieties. Pyridaben, the active ingredient in Pyramite, currently is sold in more than 20 countries worldwide for control of mites and other important insects on a variety of fruits and vegetables.
Good Timing
The EPA's late August timing for Pyramite's Section 18 was just in time for at least one Delaware apple grower, whose mite problem was getting out of control. Carlton Fifer of Fifer Orchards, Wyoming, Del., was the first grower to try Pyramite. He used it on 5 acres of his large, mature Rome Beauty trees.
Joanne Whalen, extension IPM specialist from the University of Delaware, found all stages of European red mites (Panonychus ulmi) in Fifer's trees during pre-treatment scouting. Her count of five mites per leaf jumped to 15-20 mites per leaf in just a few days. She also found an occasional two-spotted spider mite (Tetranychus urticae) and the presence of lady beetle and predatory mite beneficials that were not making a significant impact on the mites.
Assisting Fifer with the initial spraying was Bill Sciarappa, a New Jerseybased BASF technical representative. Sciarappa and Fifer sprayed the mites using a standard air-blast sprayer calibrated at 100 gallons per acre, mixed with 6.6 ounces of Pyramite per acre. The watersoluble packages minimized mixer/loader exposure and left nothing to dispose. Weather conditions were good, Sciarappa said, and they received very good cover with the spray.
Immediate Impact
Within 18 hours of spraying, a visible reduction in mite population was evident. Dick Coburn, a growerconsultant from Biglerville, Pa., said he thought that Pyramite provided 100 percent control.
"No question about it," he said. "It is a spectacular miticide from what I saw. It is an excellent material. "
Whalen agreed when she couldn't find signs of resurgence a few weeks later. "It is the absolute product of choice for summer mite control," she said. Sciarappa said research shows that these results were typical of Pyramite, which has provided between 40 to 50 days of control.
Product Background
Greg Roman, BASF market manager, said pyramite is from the chemical family Pyridazinone. The active ingredient pyridaben provides long-term residual control of all major mite pests in apples. Specifically, Pyramite provides excellent control of European red mites, two-spotted spider mites, McDaniel mites and those resistant to other products.
Although all stages of a mite's life cycle are affected by Pyramite, the immature motile stages are more susceptible than others. After testing Pyramite on Fifer's orchard, Sciarappa thought that the product
also might have affected ovicidal activity, because the mites' eggs didn't seem to hatch. However, this has not been proven in the laboratory.
BASF reports that the effectiveness of Pyramite is best evaluated seven to 10 days after application. Because of its long-lasting activity, a more accurate picture of mite control will be visible after this time.
Pyramite may be applied as a curative treatment in early through late-season applications and should be applied when mite populations are building. Thorough coverage is essential for effective control. Activity is not affected by variations in temperature. Preventatives, such as ovicides, may or may not be necessary. The unique mode of action of Pyramite is particularly effective in the management ofresistant pests. It works as a mitochondrial electron transport inhibitor to block cellular respiration, causing the pests to lose coordination and eventually collapse.
Avoiding Resistance
Using this miticide in rotation with products of different classes will help prevent resistance to Pyramite and break the cycle of resistence to other products. Some of the other modes of action that can be rotated with Pyramite include: Pyrethroids, a nerve cell membrane destabilizer; Abamectin, inhibiting nerve transmissions by affecting GABA-dependent chloride ion channels; soap and oil, damaging membranes and the waxy layer of the exoskeleton of soft-bodied insects with suffocation; growth regulators, inhibiting chitin synthesis or preventing normal development; and Organophosphate and Carbamate, preventing signal transmissions across nerve synapses by inhibiting cholinesterase.
"It's the beginning of a new era, with options to switch chemistry and rotate the old back in," Sciarappa said. "Pyramite is a more flexible, big new tool in managing resistance."
The IPM Angle
Pyramite fits into most integrated pest management programs as it is an environmentally sensitive miticide control. Most beneficial insects tested have shown little or marginal adverse effects from Pyramite applications. If initial knockdown occurs, it is typically followed by a rapid rebounding of the population. The beetle Stethorus is susceptible to Pyramite and will be suppressed if present in the orchard during application. However, populations will rebound. "Pyramite can be used as an important tool in an apple IPM program," Whalen said. "It allows producers to scout for mites and make timely applications resulting in economic returns."
BASF thinks Pyramite fits well into a system of delayed dormant oil treatments, followed by scouting. The company recommends reviewing current IPM program to receive the optimum benefit of this miticide.
By Amanda Williams. Reprinted from The Grower.
Top