Last year a fungus was found to perhaps be effective; this year scientists say there "could be a turning point."
The latest tests on ways to kill the spotted lanternfly are showing promise.
This summer, the Center for the Agricultural Sciences and a Sustainable Environment at Penn State Berks became ground zero for research of organic and conventional methods to eradicate the destructive pest.
After discovering last year that two kinds of fungi might do significant damage to the Asian spotted lanternfly population, further testing is bearing fruit.
A common North American fungus could be the key to the downfall of the winged invader. Early findings from studies underway at the center at Penn State Berks by scientists from Penn State Berks and Cornell University, Ithaca, N.Y., are lending hope to the fight against what has been described as the worst invasive pest to hit the U.S. since the gypsy moth.
The center at Penn State Berks is in the heart of Pennsylvania's quarantine zone and is one of the primary research sites studying methods of controlling the lanternfly through a Pennsylvania Department of Agriculture grant.
Grape vines that they put lanterflies on, and then treated with fungus. They have bags on them to keep the lanternflies from moving from plant to plant. (Reading Eagle: Ben Hasty)
Researchers from Penn State approached Dr. Michael Fidanza, professor of plant and soil science and director of the agricultural sciences center at Penn State Berks, about using the site for research over the summer.
Fidanza agreed to provide use of a 3-acre tract of land and equipment for the study. In addition, Dr. David Sanford, associate professor of ornamental horticulture at Penn State Berks, allowed the team to use his research lab and part of the shade house.
The team includes researchers from Penn State Berks, Penn State's College of Agriculture Sciences, the Penn State County Extension and Cornell.
Study fueled hope
The team's latest research was inspired by a Cornell-led study that showed that two fungi, Batkoa major and Beauveria bassiana, were decimating spotted lanternflies in the woods of Berks County, near the Pagoda and in Antietam Lake Park in Lower Alsace Township last year.
Found naturally in soil, Batkoa major and Beauveria bassiana are native fungi that cause disease in insects but are harmless to humans. Beauveria is already an ingredient in some Enivronmental Protection Agency-approved biopesticides that are environmentally friendly and usually affect only the target pest and related organisms, said Penn State scientist Nina Jenkins, senior research associate in entomology.
Jenkins was instrumental in the creation of Aprehend, an EPA-registered biopesticide developed at Penn State that has revolutionized bed bug control.
When an insect encounters these fungi, it picks up fungal spores, which germinate and colonize the body, killing the insect in days.
A telltale sign of fungal infection is a white fuzz that emerges from the cadaver days after contact. That fuzz, in turn, contains more spores that can infect other insects, Jenkins wrote in a statement.
Because the spotted lanternfly is an introduced species and not closely related to any native insects, finding predators or parasites that will feed on it is much more difficult.
At the center, much of the groundwork is done by John Rost, lab supervisor for biology and horticulture, along with two graduate students from Penn State University Park campus. They are joined a few times a week by other members of the research team.
Native to Asia, the spotted lanternfly was first discovered in the U.S. in 2014 in Berks County. Since then, it has spread to 13 other counties in Pennsylvania and has been found in New Jersey, Virginia, Maryland and Delaware.
The lanternfly threatens Pennsylvania's grape, tree fruit, hardwood and nursery industries, which collectively are worth about $18 billion to the state's economy, a Penn State statement said.
“We heard from Korea that they like peaches, but we have seen them in lower numbers on peaches here,” said David Biddinger, tree fruit research entomologist at Penn State. “The biggest problem for agriculture has been grapes. They really like grapes. If they hit the same vines two years in a row, the vines die.”
In July, scientists set research plots where dense populations of spotted lanternfly nymphs were observed. The plots had a control group and an experimental group, each 50 feet wide by 30 feet deep; all contained the tree of heaven — the insect's preferred host — and other species that are attractive food sources, including walnut and bittersweet, a Penn State statement said.
Using hydraulic sprayers that reach up to 30 feet, the control sections were treated with water. The experimental tracts were sprayed with a commercial biopesticide containing the Beauveria fungus in water.
Trays collected falling insects. Mortality levels between the water control plot and the adjacent Beauveria plot were compared. Tree leaf samples were collected and taken to a laboratory to see how long the fungus would last.
Dead spotted lanternflies and any nontarget insects collected are being tested at Penn State Berks to determine if the biopesticide caused their demise and, if so, to what degree.
Scientists want to minimize the risk to beneficial insects such as bees.
John Rost, a research technician with Penn State Berks, with containers of lanternflies that on which they did field tests of the fungus. (Reading Eagle: Ben Hasty)
“Could be turning point”
While they are still poring over data, the scientists were encouraged to see that, two weeks after spraying, the number of live lanternflies in the fungus-treated areas was about half as many as those in the control areas. They now are replicating their experiments, this time on mature lanternflies, which will be more challenging because adults tend to congregate higher on the tree. If results continue to be positive, future exploration would focus on the development of formulations of several biopesticide products proven to be effective on the spotted lanternfly, which perhaps could be used for aerial spraying of large tracts of land.
“We are cautiously optimistic,” Biddinger said. “More needs to be studied, but if this research pans out, it could be a turning point. Time will tell.”
The destructive spotted lanternfly was first discovered in the U.S. in Berks County.
It may have hitched a ride in a shipping container.
It has been detected in 14 counties: Berks, Bucks, Carbon, Chester, Dauphin, Delaware, Lancaster, Lebanon, Lehigh, Monroe, Montgomery, Northampton, Philadelphia, Schuylkill.
By Beth Brelje