Biotech Updates

OxO Maize Confirmed More Resistant to Corn Borer

May 4, 2007

The genetically modified maize containing the wheat oxalate oxidase (OxO) gene was found to be more resistant to European corn borers (ECB). The result from the recent study by a group of researchers in Ottawa, Canada confirms earlier findings about the OxO maize.

The OxO maize lines have phenolic concentrations that are significantly higher than non transgenics. In addition, the transcription of a 13-lipoxygenase gene, coding for a key enzyme involved in the regulation of secondary metabolism, is likewise higher.

The researchers believe that the high levels of soluble phenolic acids, in particular ferulic acid, contributed to the insect resistance of the OxO maize. They have found an inverse relationship between ferulic acid concentration and the ECB larval growth rate. Field testing showed that leaf consumption and stalk-tunneling damage caused by ECB were significantly reduced by 28-34 and 37-39%, respectively, on all of the OxO lines that the researchers tested.

The paper published by the Journal of Agricultural and Food Chemistry can be accessed by subscribers at http://dx.doi.org/10.1021/jf063030f.