Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Corn earworm moths get a lift from the wind

15.01.2004


Most corn earworms cannot survive the cold of a Northeastern winter, but each summer this sweet corn pest arrives back in the cornfields of the northeastern United States more quickly than most people believe is possible. Now, a team of Penn State meteorologists thinks it knows how the small moths travel long distances so quickly, and perhaps can predict where and when they will appear next.



"For years, researchers have assumed that the moths travel in parcels of air," says Matthew Welshans, undergraduate in meteorology and undergraduate research assistant at Penn State’s Environment Institute. "Few had actually tested this assumption, and no one tried to predict where or when the moths would land and earworms would appear in the Northeastern states."

Working with Dr. Shelby Fleischer, professor of entomology; Paul Knight, Penn State meteorologist; and Dr. Douglas A. Miller, assistant professor of geography, Welshans investigated the potential paths of corn earworm moths and other pests such as armyworm if they rode the wind as they spread northward during the spring and summer.


"We found a discernible trend that the corn earworm travels at some height and is impacted by the direction of the air currents," he told attendees of the 84th annual meeting of the American Meteorological Conference today (Jan. 14). "Depending on the time of day, the travel height could be from 500 meters (1640 feet) to a kilometer (3274 feet)."

The corn earworm larva is a major pest of sweet corn that destroys the top of the corn cob. While they will eat both field and sweet corn, a little damage to tops of field corn is irrelevant, while a chewed-up ear of sweet corn is not marketable.

"The northeastern United States accounts for more than 100,000 acres of sweet corn, or about a third of the total crop in the U.S.," Welshans said. "The crop was valued at more than $147 million in 2000."

The corn earworm moth lays its eggs on the corn silk but will lay them on other parts of the plant if the silk is not available. The eggs hatch in 2 to 10 days into small larvae that eat down the corn silk into the kernels at the tip of the ear. Because corn earworms are cannibalistic, usually only one or two larvae make it to the tender kernels. Eventually they drop to the ground and burrow in to pupate and emerge from the ground as moths. In the south, the earworms can have three generations per season with the last pupae wintering over before emerging to restart the cycle. In the north, assuming ground temperatures are normally cold, the winter-pupated insects freeze in the ground.

"Each year, in Pennsylvania, new corn earworms must fly into the area and repopulate," says Welshans. "But, the population grows much faster and greater than a slow move northward."

The researchers used a real-time tracking program called PestWatch that already exists in the Northeast. PestWatch uses blacklight traps that capture male and female moths and pheromone traps that capture male corn earworm moths. Individual volunteers count the insects in the traps once a week and report back to the PestWatch researchers at Penn State. The annual spread of the pest is put online so that farmers can see where insects are showing up (www.pestwatch.psu.edu).

Using this real pattern of insect population, along with a model developed by the National Oceanic and Atmospheric Administration to show wind patterns and a weather forecasting model to predict weather patterns, the researchers compared the actual pattern of insect appearances to that predicted by the wind and weather models.

"We want to be able to forecast when and were the moths, and subsequent larvae, will show up so that we can target the insects," says Welshans. "Then farmers can tailor the insecticides to reduce the amounts used or change their harvest or culling efforts."

With the two models and up-to-date information on where moths are, the Penn State researchers can not only track the insects but can also look backward at their paths to see where they are coming from and forward, to see where they will hit next.

"We are currently working on a flash program to animate the trajectories and integrate the PestWatch data so we can see the paths forward or backward," says Welshans. "Hopefully, this will be on-line for summer 2004."

One problem with the model is that volunteers only check the traps once a week so information tends to lag behind actual movement of the moths. However, because the various volunteers check their traps on different days of the week, using that to fill the time lag might be possible.

A’ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu/
http://www.pestwatch.psu.edu

More articles from Agricultural and Forestry Science:

nachricht Faba fix for corn's nitrogen need
11.04.2018 | American Society of Agronomy

nachricht Wheat research discovery yields genetic secrets that could shape future crops
09.04.2018 | John Innes Centre

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>