Weed Science Meet Looks At Risk Of Runaway Crops

Creating super varieties through genetic modification and introducing new crops could open a Pandora’s box of problems, according to some leading weed scientists.

Farmers have long battled introduced crops such as kochia – a drought-tolerant, prolific forage that is now one of the most abundant weeds in North America.

“The invasion by crops is not a new phenomenon,” University of Alberta scientist Linda Hall told attendees at the Canadian Weed Science Society’s recent annual meeting.

Three potential threats were raised at the conference – introduction of novel traits to combat abiotic stresses, such as drought or excess moisture, or to offer improved nitrogen use efficiency; importing foreign species for uses such as biofuel product ion; and plant molecular farming of existing crops for industrial, non-food and non-feed applications.

Novel traits such as drought tolerance have obvious benefits, but weed scientists worry they might “jump the fence” and cause unforeseen problems.

“We have no history of drought-tolerant canola. So how do we go about assessing the risk potential?” asked Hall.

Industry is calling for “clear lines on the road” as they seek to bring novel plant traits and “molecular farming” into agricultural production, said Hall, but in many cases, innovation is outpacing public policy.


FRIEND OR FOE:Potentially useful plants can also become weeds.

Since 2009, 61 plants with novel traits have been authorized for unconfined environmental release, said Gini Ardiel-Hall of the plant biotechnology risk assessment unit of the Canadian Food Inspection Agency.

The situation is becoming more compl icated as globalization, changing markets, and climate change push innovation in agriculture, including the introduction of new species and molecular farming.

One example of the latter is genetically modified safflower, which is being developed to produce insulin. One of the most popular new crops is camelina, which although previously considered a weed, is predicted to reach 10 million acres sown in North America by 2013, mainly for use as a biofuel. Then there’s castor bean, which has potential as a non-petroleum- based fuel or lubricant but contains the deadly poison ricin.

These types of crops have exposed gaps within the existing regulatory structure, said Ardiel-Hall.

The CFIA has no regulatory system for large-scale planting of newly introduced crops or plant molecular farming, although existing loopholes may be covered by overlapping rules for imports used as food or feed. As a result, there is currently no commercial production of molecular farming crops that require segregation.

“There is a clear need for a regulatory pathway for developers,” she added.

Some scient ists are looking to Australia as a potent ial model . That country has enjoyed some notable successes, such as eradicating kochia, which quickly spread as a weed after being introduced as a forage crop. The Australians have developed a weed risk assessment model which looks at history of weediness, climatic mapping and specific traits.

Some scientists have used that model to warn that camelina is a potentially invasive pest for Montana’s rangelands, noted Hugh Beckie, a research scientist at AAFC Saskatoon specializing in herbicide-resistant plants.

However, the Australian model is criticized by some for being “paper based” and too of ten leading to inconclusive results.

“Do we need an alternative or complementary tool to assess weediness?” asked Beckie.

One solution put forward at the conference by an American researcher was a “demographic analysis” which looks at the ability of a plant to reproduce under the environmental conditions of its new home.

But entrepreneurs such as Jack Grushcow of Vancouver-based Linnaeus Plant Sciences fear that nervous scientists and regulators will block innovation.

Novel crops could help the environment by producing fuel and lubricants from non-petroleum sources and some specialized production could see farmers earning as much as $1.50 per pound instead of 10 or 12 cents, he said.

“Many of you may look at a new crop and say, ‘Great, another potential weed,’ but I want you to understand what the impact is for the environment, jobs, and the development of petroleum substitutes, and give you good reasons to seriously consider why some of these new crops need to move forward,” said Grushcow.

daniel. winters @ fbcpublishing.com

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