By David B. Miller.
Paper Damps are among the world’s most destructive pests of paper, but they’re also among its most benign.
They have no direct effect on the paper they eat, so they don’t kill the paper itself, and their larvae can be carried off by pests like the paper moth.
In a paper published in April in the journal Science, researchers found that the larvae of the paper moths that feed on the leaves of leaves in a laboratory setting are less susceptible to the effects of pesticides than those that feed in nature.
The paper moth larvae were more susceptible to two of the pesticides, neonicotinoids and imidacloprid, than the larvae fed on leaf litter in the wild.
These findings indicate that a key to eliminating paper damps in nature is a proactive approach that combines natural control with better-regulated use of pesticides in the soil and other natural environments.
“We were surprised to find that the paper beetles that feed upon leaves in the lab have a much higher mortality rate when compared to those that were fed in the field,” says coauthor Michael B. Burt, a biologist at Rutgers University.
“It was a little surprising, but it suggests that the pesticide-management programs we have in place are working well.”
The paper moth’s success in reducing the paper dampens is also a strong indicator that they are not a threat to the rest of the landscape.
The insects don’t seem to be particularly sensitive to environmental factors, but when conditions change, they can develop resistance to pesticides.
“The paper moth has a long history of being a pest of the soil,” Burt says.
“They’ve been there for millions of years.
We think that this is the most natural response of these insect to changes in soil.
We are in a position to predict when it will be important for farmers to take these kinds of precautions.”
Paper beetles feed on a wide variety of plant materials, from bark to leaves, including pine needles, twigs, and other woody debris.
The larvae can take up to a year to reach maturity, and they typically live for around 10 to 15 days.
The first generation of paper beetles was only introduced to the United States in the 1940s, and in recent years the insects have been expanding their range into Europe.
Burch and colleagues noticed that, in addition to a reduced dampening effect of neonic and imipestic pesticides on leaf surfaces, paper beetles also ate more and more leaf litter from European and Asian plants.
In addition, a recent study showed that the species that eat paper are less likely to be resistant to neonic insecticides.
“Paper beetles have been on the rise since the 1950s,” Burch says.
That’s not surprising, because the insect is the only one of the four important groups of insects that have evolved the ability to metabolize and release chemicals that have been implicated in dosing of pesticides.
The most important pesticide that paper beetles are exposed to is the insecticide imidazoline.
Bunch and his colleagues noticed the paper beetle larvae were much more resistant to the herbicide imicofluorocarbons (imf), the pesticide that is widely used in agriculture and is also known to be toxic to the paper-eating beetle.
Imf is also the only herbicide that has been shown to kill the larval stages of the beetle.
The study found that, while imf is a common pesticide, imf-treated paper beetles were less resistant to imf than the untreated larvae.
The team also found that paper beetle-feeding insects had much higher levels of resistance to imidacarb, the pesticide most commonly used to control paper beetles in North America.
Imidaclops is an insecticide commonly used on trees and other hardwoods.
Iminaclopd has also been shown in studies to cause damage to the larva and the adult pupa of the moth.
“If the paperworm survives, it can potentially become a major pest in the future,” Bunch says.
This study was funded by the National Science Foundation, the Bill and Melinda Gates Foundation, and the National Institutes of Health.
Baughman and Burt report their findings on April 2, 2018.
Contact reporter Megan DeFronzo at [email protected]
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