Featured Research

from universities, journals, and other organizations

Bt Corn Variety Study Shows No Adverse Effect On Black Swallowtail Caterpillars

Date:
June 9, 2000
Source:
University Of Illinois At Urbana-Champaign
Summary:
A Bt corn variety grown widely in East Central Illinois in 1999 had no adverse effect on black swallowtail caterpillars that thrive in weeds alongside cornfields, according to both field and laboratory studies at the University of Illinois.

CHAMPAIGN, Ill. -- A Bt corn variety grown widely in East Central Illinois in 1999 had no adverse effect on black swallowtail caterpillars that thrive in weeds alongside cornfields, according to both field and laboratory studies at the University of Illinois.

Related Articles


The study -- published online Tuesday (June 6) by the Proceedings of the National Academy of Science -- differs sharply from a May 1999 Nature report in which Cornell University researchers, citing laboratory tests, reported that genetically modified Bt corn slowed the growth and led to early deaths of Monarch caterpillars.

Black swallowtail larvae, the UI researchers noted, are just as likely as are monarch caterpillars to encounter corn pollen in the field during a key developmental time between late June and mid-August. "Yet under actual field conditions, no mortality directly or indirectly attributable to ingestion of endotoxin-containing corn pollen could be detected," they wrote.

In field tests, researchers grew Pioneer variety 34R07, which contains Monsanto event 810 -- a particular genetic configuration of corn carrying the gene that encodes the Bacillus thuringiesis toxin fatal to European corn borers, which ravage corn crops in some parts of North America. Pollen from the Bt corn was carefully monitored and measured at a variety of locations ranging from 1/2 meter to 7 meters from the cornfield.

"We found that many caterpillars died, but not, as far as we could tell, due to anything connected to the corn or the corn pollen," said May Berenbaum, head of the UI entomology department. "There was no correlation between mortality and distance from the cornfield or between mortality and pollen load."

Some of the deaths were directly attributed to predation by spiders, carnivorous insects and other environmental factors, the researchers said. Black swallowtail females can lay up to 800 eggs during their two-week lifetime; overall life expectancies for caterpillars in the field invariably are low.

"We also measured the weights of the surviving caterpillars, and we found no negative pattern suggesting a problem in their growth and development," said UI entomologist Arthur R. Zangerl.

In the laboratory, the researchers exposed more caterpillars to Bt corn pollen from the plants in the field, as well as pollen from non-modified but genetically similar corn plants. The endotoxin from the same Bt corn again had no effect on survivorship of the caterpillars, nor did the pollen from non-modified corn. Pollen from another transformed variety, Novartis Max 454, however, did cause mortality in the laboratory. Antibody assays of the Novartis event showed that it contained 40 times as much endotoxin on average than did the 810 variety.

"This is not the green light for all forms of genetically modified organisms," Berenbaum said. "In this study, we examined only one GMO event -- just one genotype of Bt corn -- in the field. This report does, however, suggest that there are ways to reduce the risk to non-target organisms at the very least by event selection."

The UI Environmental Council, a campus organization devoted to environmental research, education and service, funded the study with a grant to C. Lydia Wraight, an undergraduate entomology student who worked with Zangerl, Berenbaum and graduate student Mark Carroll.


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Bt Corn Variety Study Shows No Adverse Effect On Black Swallowtail Caterpillars." ScienceDaily. ScienceDaily, 9 June 2000. <www.sciencedaily.com/releases/2000/06/000607074238.htm>.
University Of Illinois At Urbana-Champaign. (2000, June 9). Bt Corn Variety Study Shows No Adverse Effect On Black Swallowtail Caterpillars. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2000/06/000607074238.htm
University Of Illinois At Urbana-Champaign. "Bt Corn Variety Study Shows No Adverse Effect On Black Swallowtail Caterpillars." ScienceDaily. www.sciencedaily.com/releases/2000/06/000607074238.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com
Raw: Baby Okapi Born at Houston Zoo

Raw: Baby Okapi Born at Houston Zoo

AP (Nov. 20, 2014) The Houston Zoo released video of a male baby okapi. Okapis, also known as the "forest giraffe", are native to the Democratic Republic of the Congo in Central Africa. Video is mute from source. (Nov. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins