The Canadian flax industry is continuing efforts to rid the countryside of a genetically modified variety, but officials conceded last week they may never know how CDC Triffid proliferated in the flax supply.
According to Flax Council of Canada president Barry Hall, the council was confident in the late 1990s that all stocks of CDC Triffid had been removed from the pedigreed seed system.
He said the council contacted Value Added Seeds (VAS) in late 1997 and asked the company’s seed grower members to voluntarily remove the variety from their pedigreed seed stocks.
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Value Added Seeds was the company licensed to multiply and sell CDC Triffid to commercial flax growers.
In the spring of 1998, when pedigreed seed supplies were poised to enter the commercial marketplace, 65 to 70 seed growers in Alberta, Saskatchewan and Manitoba were thought to have an estimated 4,000 tonnes of foundation, select and certified Triffid in their seed inventories.
“It took a lot of talking and a lot of convincing, but at the end of the day, we had excellent co-operation from the company and the growers,” Hall said last week.
“To the best of our knowledge, the seed lots were destroyed…. The council on behalf of its members … were quite confident that we had stepped up and dealt with the potential problem and were quite accurate in saying that there had never been commercial production of CDC Triffid.”
However, disposal of pedigreed Triffid may not have been as thorough as the council had hoped.
In an article that appeared in the Western Producer in February 1998, Value Added Seeds president John Allen estimated that 90 percent of Triffid seed would be shipped to flax crushers.
He said some VAS seed growers were holding onto Triffid supplies in hopes that the EU would soon approve the genetically modified variety.
Triffid seed retained by seed growers would be marked with grain confetti, the article suggested.
Dale Adolphe, executive director of the Canadian Seed Growers Association, said last week he was unaware that pedigreed seed growers had withheld any CDC Triffid.
“To be honest, that’s the first time that I’ve heard that,” Adolphe said.
“But I would say that if it were true, we should find hot spots in the commercial deliveries. There should be hot spots around any seed supplies that were kept.
“My understanding of the testing that’s been done on commercial flax (in 2009 and 2010) is that everything is below 0.1 percent … (and the positive tests) are spread across the entire growing area.… I don’t think there’s been anything in the testing regime to this point that would indicate that what John Allen said back in (1998) is true.”
Adolphe said the CSGA began reviewing seed grower records in late 2009 when questions began to arise about the potential sources of CDC Triffid contamination.
He said the CSGA contacted one-third of seed growers who produced CDC Triffid and determined that Triffid supplies that had been removed from the pedigreed seed system were shipped to a variety of destinations.
Most seed was sent to a crushing facility in Altona, Man., he said.
Some Triffid produced in Alberta was shipped to a crusher in Montana and other supplies went to other American crush plants.
The flax council said tests conducted since Dec.1, 2009, on 2,500 samples of commercial flax have uncovered widespread contamination of Canada’s commercial flax supplies at levels below 0.1 percent.
Nine percent of samples submitted, or roughly 225 samples, have tested positive for traces of GM material.
“Triffid is very, very widespread (and) there is no specific geographic area,” Hall said.
Retention of CDC Triffid supplies in the late 1990s is not the only possible source of contamination.
Producers who participated in a flax industry conference call last week suggested volunteer flax plants in commercial growers’ fields and in seed growers’ plots are another potential source.
Gordon Rowland, a flax breeder from the University of Saskatchewan’s Crop Development Centre, said the volunteer rate in flax is low and the possibility of contamination through volunteers is remote.
Other growers suggested cleanout procedures used by pedigreed seed producers do not offer a foolproof guarantee that all flax seeds have been removed from augers, drills, combines, sieves and seed cleaning equipment.
Even if seed growers thought they had disposed of all Triffid supplies, seeds stuck in augers, storage bins or seed cleaning equipment could have been transferred unknowingly to other flax varieties.
Adding to the confusion is the fact that two other seed varieties developed at the U of S – CDC Normandy and CDC Mons – have also tested positive for traces of GM material.
Tests conducted on breeder seed for those varieties uncovered trace levels of GM material in December 2009.
SeCan and FP Genetics, the companies licensed to sell the varieties, have contacted all seed growers who produced them and have taken steps to remove all remaining seed supplies from the pedigreed seed system.
Dorothy Murrell, managing director of the Crop Development Centre, said Normandy and Mons represented less than one percent of western Canadian flax production in 2009.
However, at the height of its popularity in the late 1990s, Normandy commanded 14 percent of the Canadian market, she said.
In 1998, Canadian flax growers produced almost 1.1 million tonnes of flax.
Based on Murrell’s figure, Normandy production could be estimated at roughly 155,000 tonnes.
She said the CDC continues to test other lots of breeder seed from Normandy and Mons in hopes of determining whether contamination was limited to a few specific lots of breeder seed or whether it occurred across the variety.
Murrell said the CDC is still not sure how breeder seed would have become contaminated.
However, she said the genome of a self-pollinated crop such as flax would remain intact in subsequent generations of production, which suggests that if GM material is present in the genome of breeder seed, it would also be detectable in subsequent generations of pedigreed and commercial seed.
“We’re puzzled ,as is the entire industry at large, over this whole situation,” Murrell said.
Murrell said it is still unclear whether breeder seed from the two contaminated CDC varieties were used in the pedigree of other flax varieties developed at the U of S.
Results of subsequent DNA tests conducted on CDC breeder seed will be shared with the flax council and will not be considered confidential by the CDC, she added.
