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Consumers Prefer Genetically Engineered Sweet Corn and Potatoes in GM Labelling Study

11.sep.01, Food Safety Network Press Release, Food Safety Network Press Release

HILLSBURGH, ON -- For the second year in a row, customers at Birkbank Farms in Hillsburgh, Ontario can choose between genetically engineered (GE) and conventional varieties of sweet corn and potatoes: and once again, they're choosing GE by a margin of at least 3:2.

"This year, many of my customers are specifically asking for the Bt sweet corn because they like the idea that the corn is produced without insecticides," said farmer Jeff Wilson, the owner and operator of Birkbank Farms. "But more of them are concerned about whether the corn is bi-coloured than whether it is GE, with many asking for the non-existent peaches-and-cream variety, or for one colour."

"This year, many of my customers are specifically asking for the Bt sweet  corn because they like the idea that the corn is produced without insecticides," said farmer Jeff Wilson

Although the farm project offers consumer choice based on crop production methods, Dr. Douglas Powell, an assistant professor and scientific director of the Food Safety Network at the University of Guelph cautioned that the voluntary labeling of a whole food like sweet corn is vastly different from the mandatory labeling of an ingredient in a processed food, especially when the label is designed to alarm rather than inform.

"Mandatory labelling is not about creating choice at all," stated Powell. "It's about targeting products, creating retailer nervousness and customer fears and ultimately removing choice from the marketplace. It's happened in many European countries and Australia, where retailers have rushed to remove genetically modified ingredients from products rather than label. And in Ontario, major retailers have refused to carry labeled, genetically engineered sweet corn for fear of controversy."

At the Birkbank Farm market, the sweet corn and potatoes have been harvested and segregated, and are now available , fully labeled with additional information on Bt crops and the insecticides used. Last year, Wilson found that his customers preferred the Bt sweet corn over the conventional variety by a margin of 3:2. Sales are being tracked again this year and so far the trend is the same, with 325 dozen of the Bt sweet corn sold compared to 230 dozen conventional since sales began on Aug. 24, 2001. Last year, Wilson found it too difficult to track sales of 10 lb bags of potatoes because potatoes are sorted primarily by size, and will not track sales this year.

According to Wilson, the genetically engineered Bt sweet corn and potatoes he started using last year have provided an effective pest management option that allowed him to reduce insecticide use while producing the high quality vegetables his customers demand.

"This was a challenging summer for managing pests," said Wilson. "The three straight weeks of 30 degree C weather reduced my options for controlling the worms on the sweet corn. The Bt crops allowed me to focus more time on irrigation rather than spraying and the message I got from my customers last year -- and again this year -- was that they like the fact the Bt crops reduce sprays."

This year, Wilson once again found that the Bt sweet corn required no insecticides and the Bt potatoes provided effective management of the Colorado potato beetle, the number one pest of Ontario potatoes. The conventional corn was sprayed twice with insecticides and the potatoes were sprayed with an insecticide called Admire. All of the products used have been approved for safety by Canadian regulators and were used according to recommended guidelines to ensure safety.

The results from last year's study have been submitted to a scientific journal for publication. From an economic perspective , Wilson last year found an advantage only in the first planting of Bt sweet corn, which coincided with peak insect pressure. However, this does not take into account other advantages, such as the reduced risk to himself and his workers from drifting spray, and the time savings which allowed him to concentrate more time in other areas of his farm operation. Segregation and labeling involved in the marketing component of the project were also time consuming activities, the cost of which should also be taken into account when determining economic considerations of planting Bt crop varieties, if such marketing initiatives are planned.

Samples of the sweet corn are available, free, on weekends from 12 p.m to 5 p.m, through the remainder of September. Since the project began last spring, the farm has been completely open to the public with a 4 km self-guided walking trail so customers can stroll through the fields and see for themselves some of the challenges Wilson faces as a farmer.

The crops are part of a continuing farm-to-fork study with the University of Guelph that began in June 2000. The project compares different pest management technologies and consumer reaction.

A web site containing numerous background documents, last year's results, weekly updates on the crops' development, and consumer buying patterns, can be found at:

A series of videos chronicling the production of Bt sweet corn this year from planting to consumption is available at:

A backgrounder on the Bt sweet corn is available below.

This research was supported by the Council for Biotechnology Information, and the Ontario Ministry of Agriculture, Food and Rural Affairs,

Related Files

Filename File Type File Size Date
bt_backgrounder.pdfPDF File67.46 KB29.Sep.11