Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biocontrol Option for Soybean Aphid Tested

12.12.2008
A program supported by university researchers, farmers and soybean groups is introducing tiny parasitic insects to control soybean aphids in South Dakota and neighboring states.

South Dakota State University soybean research and Extension entomologist Kelley Tilmon said there have been 10 releases of the insect, Binodoxys communis, at points in eastern South Dakota since the program won federal and state approval to proceed in 2007.

Tilmon is part of a group of 14 scientists from five north central states and the U.S. Department of Agriculture who are overseeing the Binodoxys communis release in South Dakota and the larger region.

“The thing to understand about these releases is that they’re not mass releases of insects like butterflies at a wedding,” Tilmon said. “Rather, these are small inoculations at various points with the hope that over time, a population will become established in that area and ultimately spread from there to soybean fields throughout the state.”

In the long term, Tilmon said, the insects could make it necessary to use pesticides less often to control soybean aphid, an insect from Asia that was first discovered in the U.S. in 2000.

“Soybean aphid is actually seldom a pest in Asia, largely because there is a large suite of natural enemies that are particularly adapted to prey upon the soybean aphid,” Tilmon said.

“This is a very common pattern: When an herbivorous insect — something that’s going to be a crop pest — gets in accidentally, it usually gets in without the natural enemies that help control it in its land of origin, and as a consequence, usually becomes a much larger pest in the new range than in its native range.”

One solution, Tilmon said, is to try to restore that balance by what’s called “classical biological control.” In this case, scientists performed research in the soybean aphid’s native range, evaluated enemies of the pest insect and selected some for further study.

University of Minnesota entomology professor George Heimpel said scientists brought several parasitoids back to a federally-approved quarantine lab at the University of Minnesota, specially designed to prevent accidental release.

The parasitoids pose no threat to humans or pets, but scientists wanted to evaluate whether they would harm other aphids besides the soybean aphid.

At the Minnesota quarantine lab, researchers selected one that preys almost exclusively on soybean aphid. Scientists filed an application with the U.S. Department of Agriculture in January 2006 for permission to release the parasitoid.

Permission was granted in April 2007, after two experts from the U.S., two from Canada and two from Mexico gave approval.

Tilmon said because Binodoxys communis is a soybean aphid specialist, it’s not likely to cause problems for other non-pest insects. In addition, the parasitoid doesn’t stray far from the habitat of its host insect, making it unlikely to become a nuisance for humans.

“These parasitoids are wasp relatives,” said Tilmon.

“They’re in the same family as wasps, but they’re not wasps in the sense that we think of large, stinging creatures. These are really more the size of gnats,” she described.

“I measured one once and it’s about the size of a comma at the end of a sentence in your typical printed text. They are biologically incapable of stinging people.”

As part of its reproduction cycle, Tilmon said the female Binodoxys communis deposits an egg inside a living aphid. The egg hatches into a larva that feeds inside the aphid. The aphid eventually dies and forms a protective shell or “mummy” around the developing parasitoid pupa. The adult parasitoid then exits, leaving the mummified aphid shell behind.

Tilmon cautioned that only about half of the parasitoid introduction attempts over the decades have resulted in successful establishments. Even if the Binodoxys introduction is successful, it won’t mean that producers need to stop monitoring for soybean aphid and using pesticides to control aphid, but it may mean they’ll need to spray less often. And if Binodoxys gets established, whatever biological control it provides will be free; producers won’t have to pay year after year for it.

The South Dakota Soybean Research & Promotion Council helps fund Tilmon’s ongoing work.

"For soybean farmers, I think it will be very helpful to have more options to control soybean aphids,” said Astoria producer David Iverson, chairman of the South Dakota Soybean Research & Promotion Council.

“Currently farmers can control aphids with pesticides,” he said.

“To have the aphid population reduced with natural predators would be great for soybean producers and good for the environment as well. We are fortunate to have Kelley Tilmon doing this type of research.”

In addition, the North Central Soybean Research Program and the Iowa Soybean Association use checkoff dollars to support the biological control project against soybean aphid. The NCSRP was recently nominated for the International IPM Achievement Award for supporting this regional project, which has resulted in releases in seven states.

In South Dakota, it’s a collaborate effort involving not only SDSU research, but also the South Dakota Cooperative Extension Service and South Dakota farmers. “Seven out of our 10 release sites were done with the cooperation of Extension educators in their respective counties, and they were done with the cooperation of soybean producers on their farms,” Tilmon said.

“The soybean producers donated the space to set up the release points and have helped to get this project going.”

“It’s really nice that this project has involved not just the university, but also the grassroots of the soybean producers in the state.”

As a result of her research and Extension work on several fronts, Tilmon won the Sherwood and Elizabeth Berg Faculty Award for 2007, given to an SDSU faculty member in the early stages of a career.

Tilmon used the award to help fund her travel to attend the International Congress of Entomology in Durban, South Africa, in 2008. The congress meets every four years in a different part of the world. Tilmon presented work on the Binodoxys communis project at the conference.

Heimpel notes that the University of Minnesota’s quarantine lab and a USDA-sponsored quarantine lab in Delaware are studying two other parasitoids for possible release against soybean aphid.

SDSU soybean research entomologist Kelley Tilmon scouts for soybean aphid eggs on a host plant, buckthorn, in early spring.

http://agbiocom.sdstate.edu/photos/Tilmon1666.jpg

SDSU soybean research and Extension entomologist Kelley Tilmon raises the parasitoid Binodoxys communis in an SDSU greenhouse for release in South Dakota soybean fields. The parasitoids are natural enemies of soybean aphids.

http://agbiocom.sdstate.edu/photos/Tilmon0682.jpg

Jeanne Jones Manzer | Newswise Science News
Further information:
http://www.sdstate.edu

More articles from Agricultural and Forestry Science:

nachricht Alkaline soil, sensible sensor
03.08.2017 | American Society of Agronomy

nachricht New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Molecular volume control

22.08.2017 | Life Sciences

When fish swim in the holodeck

22.08.2017 | Life Sciences

Biochemical 'fingerprints' reveal diabetes progression

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>