Quality characteristics of Glyphosate-Tolerant canola cultivars containing a Glyphosate acetyltransferase transgene (Event DP-Ø73496-4)

Abstract

Canola (Brassica napus L.) was transformed with an insert that expresses the GAT4621 protein, conferring tolerance to the nonselective herbicidal ingredient glyphosate. Event DP-Ø73496-4 (trade name Optimum GLY Canola) was introgressed into additional female inbred genetic backgrounds and hybrid seed lots were created to evaluate canola quality characteristics for cultivar registration in Canada. Field trials were conducted in 2012 and 2013 across several locations in appropriate maturity zones for the cultivars. Results indicated no difference for key canola quality parameters across genetic backgrounds and locations. The oil content (at 8.5% moisture) for Optimum GLY canola cultivars in these trials ranged from 40.6 to 50.3% and was within the industry range (35.6-51.2%) for samples graded Canola, No. 1 Canada from 2012 and 2013. The international standard for erucic acid in canola is <2% total fatty acids. The range of erucic acid values observed in Optimum GLY canola cultivars was lower at 0.01 to 0.14% total fatty acids. The glucosinolate content of the Optimum GLY canola cultivars ranged from 2.7 to 15.9 μmol g−1 on a whole-seed basis (at 8.5% moisture) and was comparable with the industry range (3.0-26.0 μmol g−1) for samples graded Canola, No. 1 Canada from 2012 and 2013. These findings are consistent with regulatory study results and submissions made globally in support of authorization for canola containing event DP-Ø73496-4. Optimum GLY canola is within established ranges for key industry composition parameters and will maintain canola quality standards.