Like Pavlov’s Dogs

Like Pavlov's Dogs

As spring begins, apple growers from New York to South Carolina begin to scout for pests. Among those pests is the dogwood borer, a pest that originally attacked ornamental trees but has become increasingly damaging to apple trees. A heavy infestation can girdle the base of the tree trunk, causing death in the worst circumstances.

Over the last several years, a collaborative team of researchers from Virginia Polytechnic Institute and State University, USDA, and North Carolina State University (NCSU) have been delving into the chemical ecology of the male dogwood borer and examining the egg-laying preferences of the female dogwood borer. Their experiments have led them to discoveries that may eventually lead to the control of both males and females: a sex pheromone to lure males away from possible mates, and an attractant that could potentially be used to trap females.

In the 1990s, Virginia Tech plant pathologist Keith Yoder observed that dogwood borer damage at the base of apple trees was commonly misdiagnosed as a disease. When Virginia Tech entomologist Chris Bergh learned about Yoder’s findings, he decided to explore the issue. In collaboration with USDA researchers Tracy Leskey and Aijun Zhang, and NCSU entomologist James Walgenbach, Bergh began his research with one main question: Why were commercial pheromone lures for dogwood borer not consistently effective at attracting the pest to traps?

“We compared several commercial lures, and found that although one particular lure was more effective than the others, it still didn’t appear to accurately reflect the population size,” Bergh said.
The project goal was to create a pheromone that, when used as a lure in traps, could be used to accurately and reliably monitor the presence and abundance of male dogwood borer. In addition, since sex pheromones are presently used in control tactics designed to manage other pest species of moths, the team has investigated two such approaches for dogwood borer. One tactic, called mass trapping, seeks to remove large numbers of males from the population by capturing them in traps baited with pheromone lures. The other approach, called mating disruption, relies on deploying the pheromone in slow-release formulations within the crop, disrupting the ability of males to find females. The end result of both tactics is to reduce mating and the ability of females to lay fertilized eggs on the plant.

Luring Them In

The answer to Bergh’s research question lay in the chemical composition of the pheromone lure. After months of tests, Zhang discovered three pheromone components that, when combined in the proper ratio, attracted more dogwood borers than the most effective commercial pheromone lure, and even more than female dogwood borer moths: (Z,Z)-3,13-octadecadienyl acetate (ODDA); (E,Z)-2,13-ODDA; and (Z,E)-3,13-ODDA. After tests at several sites in Virginia, West Virginia, and North Carolina, the newly developed lures consistently caught significantly more male dogwood borers than any of the commercial products.

“We had higher trap captures than anyone had seen before,” said Bergh.

After recognizing that the commercial lures lacked the exact ingredients of the dogwood borer sex pheromone, the team discovered another problem: one of the chemicals produced a by-product during synthesis that actually repelled dogwood borers from the lure. This by-product was typically present in commercial lures, helping the team understand why current trap captures were lower than the team knew they should be. To create a fool-proof lure, they would have to find a way to synthesize the chemical without producing the contaminating by-product. Bergh’s team is currently experimenting with the chemical synthesis, a project partially funded by a Southern Region IPM grant.

Field trials conducted by researchers at Pennsylvania State University over three years showed that the three-component pheromone formulation reduced dogwood borer populations — and the resulting damage — over time. The success of the Virginia Tech/USDA/NCSU team’s discovery has led to interest in licensing the patent, which would put the new pheromone on the market.

Currently, the chemical Lorsban (chlorpyrifos, Dow AgroSciences) is the only effective control for dogwood borer, but it is due for EPA review in 2009. USDA and Virginia Tech have patented the pheromone blend, and the patent is currently available for commercial licensing. Ultimately, the hope is for the pheromone to be publicly available as an alternative management tool for dogwood borer. Manufacturer interest in formulating the improved pheromone lure for commercial production has made that a more promising possibility, although nothing definite has yet developed.

“In terms of the application of this, we are still in the research and development phase,” said Bergh. “But we are getting there at a rapid rate.”

Leave a Reply

Fruits Stories
Washington Capitol building
Citrus
April 21, 2017
Alliance Stepping Up Efforts to Protect Specialty Crops
The Specialty Crop Farm Bill Alliance has kicked off its efforts to communicate to Congress its priority needs for the Read More
Apples & Pears
April 21, 2017
Interpera Congress Heads to Pacific Northwest in June
International pear conference comes to the U.S. for the first time. Read More
glass of red wine
Grapes
April 20, 2017
Would You Be Willing to Pay More for Organic Wine?
While consumers might be ready to fork over more for organic produce, study says the feeling isn't quite the same when it comes to the adult beverage. Read More
UF/IFAS scientist Jonathan Crane inspects avocado trees in South Florida
Crop Protection
April 20, 2017
Beetle Battle Burgeoning for South Florida Avocado Growers
Scientists identify more species of pests that vector deadly fungus. Read More
farm labor pic for web
Citrus
April 20, 2017
Farm Labor Is in Crisis
To have a great crop potentially rot in the field because workers can’t be sourced is probably worse than a weather event taking out production. Read More
Grapes
April 19, 2017
Donnell Brown Named President of National Grape & Wine Initiative
New president brings experience in wine industry communications. Read More
Apples & Pears
April 19, 2017
Young Apple Growers Meet with Lawmakers
Apple leaders from across the country discuss ag issues such as labor, trade, and research. Read More
Barnes Farm cabbage field in Hastings, FL
Citrus
April 18, 2017
Florida Growers Seeking Inspiration Need Not Look Far
The firsthand experience of speaking with farmers and actually seeing all the hard work, knowledge, ingenuity, and people behind where our food comes from is invaluable. Read More
Farm Management
April 18, 2017
Survey Says New York Growers Lost More than 70% of Crop Last Year
Growers say they suffered more than 50% crop losses in Western New York. Read More
Apples & Pears
April 18, 2017
Researchers Say it is Time to Scout for Apple Diseases
With bloom underway, the risk for fire blight and scab are high. Read More
Fruits
April 17, 2017
How Fruit Growers Use Biocontrols [Infographic]
The editors at American Fruit Grower and Western Fruit Grower were curious about how biocontrols are impacting the industry. So we took a look at our 2017 State of the Fruit Industry Survey to see what patterns are emerging. Here's what we learned. Read More
drought management; irrigation; water management
Citrus
April 17, 2017
Florida Flush with Water Shortage Warnings
Conservation practices preached throughout the state as exceptionally dry pattern persists.  Read More
Citrus
April 17, 2017
Natural Enemies for Asian Citrus Psyllid
The eventual spread of Huanglongbing (HLB), or citrus greening, to commercial groves in California seems inevitable. But the devastation seen Read More
Specialty vegetable farm market display
Citrus
April 14, 2017
How Florida Growers Are Agritaining and Gaining
Come one, come all — big and small — there are multiple ways to benefit from Agritourism. Read More
The Hill family of Southern Hill Farms in Florida
Berries
April 13, 2017
Florida Farming Family Staying on Top of the Blueberry Game
The Hill family of Southern Hill Farms continues to up their efforts to diversify business and stay out ahead of a competitive market. Read More
The Latest
Citrus
April 24, 2017
Who Will Be Florida’s next Woman of the …
Nomination period now open for longstanding recognition from FDACS. Read More
Citrus
April 23, 2017
Bio Huma Netics, Inc., and Mesa Verde Re…
Strategic alliance between the two companies is designed to offer customers greater access to products. Read More
Citrus
April 21, 2017
Alliance Stepping Up Efforts to Protect …
The Specialty Crop Farm Bill Alliance has kicked off its efforts to communicate to Congress its priority needs for the Read More
Crop Protection
April 20, 2017
Beetle Battle Burgeoning for South Flori…
Scientists identify more species of pests that vector deadly fungus. Read More
Citrus
April 20, 2017
Farm Labor Is in Crisis
To have a great crop potentially rot in the field because workers can’t be sourced is probably worse than a weather event taking out production. Read More
Citrus
April 18, 2017
Florida Growers Seeking Inspiration Need…
The firsthand experience of speaking with farmers and actually seeing all the hard work, knowledge, ingenuity, and people behind where our food comes from is invaluable. Read More
Farm Management
April 18, 2017
Survey Says New York Growers Lost More t…
Growers say they suffered more than 50% crop losses in Western New York. Read More
Fruits
April 17, 2017
How Fruit Growers Use Biocontrols [Infog…
The editors at American Fruit Grower and Western Fruit Grower were curious about how biocontrols are impacting the industry. So we took a look at our 2017 State of the Fruit Industry Survey to see what patterns are emerging. Here's what we learned. Read More
Citrus
April 17, 2017
Florida Flush with Water Shortage Warnin…
Conservation practices preached throughout the state as exceptionally dry pattern persists.  Read More
Citrus
April 17, 2017
Natural Enemies for Asian Citrus Psyllid
The eventual spread of Huanglongbing (HLB), or citrus greening, to commercial groves in California seems inevitable. But the devastation seen Read More
Citrus
April 14, 2017
How Florida Growers Are Agritaining and …
Come one, come all — big and small — there are multiple ways to benefit from Agritourism. Read More
Farm Management
April 12, 2017
How California’s No-Drought Status…
Find out which previous orders are rescinded as a result of the drought being declared over — and which ones are not. Read More
Fruits
April 12, 2017
An Organic Showcase Debuts at the 2017 U…
The Expo will feature more than 40 "innovative organic products." Read More
Citrus
April 10, 2017
BASF Licenses CRISPR-Cas9 Technology for…
Genome-editing from Broad Institute has potential to be a more precise tool to improve ag products. Read More
Citrus
April 6, 2017
Mild or Wild? Here Is Your 2017 Atlantic…
Possible return of El Niño climate phase could sap strength out of any stormy scenarios. Read More
Citrus
April 5, 2017
Chlorpyrifos’ Ban Reversed: Resear…
Last week, EPA declined to ban the pesticide, which had been recommended for removal during the Obama administration. Read More
Equipment
April 4, 2017
What’s New in Tractors for Vegetab…
Take a look at these new models and retrofit opitons ideal for specialty crop growing. Read More
Citrus
March 31, 2017
FMC to Acquire Portion of DuPont Crop Pr…
Deal makes FMC the fifth largest agriculture chemical company, valued at $3.8 billion annually. Read More