Pending Canadian approval of its new herbicide-tolerant rice, BASF Corp. has pulled back on a commercial launch of Clearfield rice this year. Instead, it will have a "measured" introduction in which selected growers will conduct on-farm demonstrations.

All rice coming from those fields will be directed to three participating storage facilities and segregated until the Canadian government approves the trait.

Despite the small setback, D. Chad LeBlanc, BASF rice market manager, says the company plans a full commercial launch of two Clearfield varieties in 2002. The imidazolinone-tolerant varieties allow growers to control red rice and other grasses without killing the rice crop.

The Canadian Food and Drug Act requires companies with any new heritable plant trait to first receive approval from Health Canada. The country doesn’t differentiate between traits derived from genetic engineering or through conventional breeding.

Canada also is the only country in the world to require approval of all heritable plant traits.

BASF has already gone through the Canadian review process successfully five times with imidazolinone-tolerant canola, wheat and corn. And LeBlanc says he’s confident the Canadians will also approve Clearfield rice.

BASF made the decision to scale back when it looked like the Canadian government might not approve the trait before this year’s harvest. LeBlanc says BASF officials didn’t want to jeopardize U.S. rice imports into Canada and are taking a "responsible approach."

"We didn’t want to get into a situation where we had grain that had to be identity preserved and we had to guarantee that it wouldn’t end up in Canada," LeBlanc says. "The situation around Starlink has raised the issue 300 fold."

Conventional breeding techniques

Clearfield rice was not developed from genetic engineering. Instead, the herbicide tolerance was a naturally occurring trait discovered by LSU researcher Tim Croughan, and the varieties been developed through conventional breeding techniques.

BASF and Louisiana State University's Ag Center are working together to develop the Clearfield system. Of the three varieties that LSU rice breeder Steve Linscombe had in seed expansion last year, BASF and LSU have decided to move forward with two--CL 121 and CL 141. Although each is a unique variety, CL 121 has some Cocodrie parentage, and CL 141 has some Maybelle parentage. In trials, Linscombe says the two had the highest yield potential as well as the best milling yield potential.

Horizon Ag LLC of Memphis, Tenn., will market the seed and ensure growers follow strict stewardship recommendations designed to minimize herbicide resistance and chances of outcrossing with red rice.

Originally, Horizon Ag had seed for about 100,000 acres of commercial production in addition to registered seed for 10,000 to 15,000 acres of certified seed production. The seed production will continue as planned.

LeBlanc says it's not yet been determined how many acres will be devoted to on-farm demonstrations this summer, but it won’t be nearly as much as originally planned for the commercial introduction.

The Environmental Protection Agency has granted temporary food tolerances for two years for Newpath herbicide, as the imazethapyr product is being marketed. That enables states to issue Section 24 C special local needs registrations. American Cyanamid, which BASF acquired last year, submitted registration materials for Newpath to the EPA last summer.

Based on field trials, researchers recommend growers apply a pre-plant soil-applied followed by a post application of the herbicide. The temporary tolerance allows growers to use 8 ounces total during the season.

BASF, working with Horizon Ag, is currently selecting growers in Louisiana, Texas and Arkansas who will conduct the small-field demonstrations. The rice must be shipped to Rice Belt Warehouse in Texas, Elton Rice Inc.'s dryers in Louisiana or Riceland Foods in Arkansas.

BASF also is continuing to evaluate CFX 18, which appears to be significantly more tolerant of imidazolinone herbicides than current Clearfield varieties. The trait was also discovered by LSU's Croughan.

After seed expansion this winter in Puerto Rico, BASF plans to look at it further in Mid-South field trials this summer. If the new variety performs well this season, BASF and LSU could possibly release it for registered seed production for 2002.