Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Determine Temperature-Driven Rootworm Forecast

09.06.2005


Western corn rootworm can chew through as much as $1 billion yearly due to lost production and treatment costs across the corn belt.



But two Texas Agricultural Experiment Station entomologists think they can reduce these losses with a new model to predict and better target the pests.

The model developed by Dr. Jerry Michels, Experiment Station entomologist in Bushland, and Dr. Marvin Harris, Experiment Station entomologist in College Station, is based on temperature and number of adults emerged.


While crop rotation is the best way to control the corn rootworm, many corn growers don’t have that option. So producers spray. Timing of the spray is critical, Michels said.

As much as 25 percent of the yield loss is from the adults clipping the silks, but the greater damage is done by the larvae, chewing off the roots of the corn and causing it to fall over, he said. As much as 75 percent of the crop can fall over.

"The idea behind this is to control more adults before the fall, so the number of eggs and resulting larvae the next spring will be lessened," Michels said.

He started collecting data on adult western corn rootworm emergence in 1996. Nine years of catching adult beetles in traps and comparing the data with temperature data from the North Plains potential evapotranspiration network helped the researchers determine emergence patterns.

"The emergence pattern of the beetles is quite variable for a given year," Michels said. "However, because it is temperature-driven, the model is flexible and can account for differences in emergence due to normal, cool or hot years."

This flexibility can improve Western corn rootworm management decisions by showing when an insecticide application will do the most good, Michels said.

The model has been incorporated into the North Plains PET weather station network. Daily model output can be accessed by going to http://amarillo2.tamu.edu/nppet/station.htm, the weather station network site. Select a station, then go to faxes and then to the date.

The recommendation is for producers to wait until they see about 50 percent emergence, he said. Because residual of most of the chemicals is a week to two weeks, a producer would miss a large part of the population by spraying too early, Michels said.

"We can control adults and if we get rid of enough of them, it will lessen the impact," Michels said. "If we can have a model to tell our producers when we have about 50 percent adult emergence, the producer can make an application at that time."

Over the years, he said, the model is showing 50 percent emergence can come anytime from July 13 to Aug. 15.

"If it is a hot year, emergence will be earlier than a cool year," Michels said. "So rather than saying we need to spray on July 15, some years it might need to be delayed."

"We feel this is a robust model," Harris said. "We think of this physiological model as providing us a bus schedule.

"When we have the bus schedule saying 25 percent of the adults will be out and active, we can go to the field and meet that bus and actually census the number of adult beetles there," he said.

A field census of beetles represents about one-fourth of what is actually there, Harris said.

"If the number is significant enough, we institute management. It lets us orient in time to make management decisions," he said. "When we incorporate this to overall management, we will limit pesticide usage to when it is needed."

Dr. Jerry Michels | EurekAlert!
Further information:
http://www.tamu.edu

More articles from Agricultural and Forestry Science:

nachricht Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>