Field Performance of GM Potatoes With LB Resistance Gene

The potato and tomato late blight (LB), caused by the fungus Phytophora infestans, remains one of the most costly and destructive plant disease worldwide. Control of late blight mostly relies on applications of fungicides. Recently, the late blight resistance gene, RB, was identified. Scientists from the University of Wisconsin-Madison and the United States Agricultural Research Service (USDA-ARS) have successfully introduced the resistance gene to commonly cultivated potato varieties. A new paper published by the journal Plant Disease presented the results of a two-year field trial on the efficacy of the transgenic potato lines in combating the late blight pathogen.

All the potato lines containing the RB gene exhibited stronger foliar resistance compared to their non-transgenic counterparts. RB-containing tubers, however, failed to exhibit increased resistance to the blight pathogen. The scientists hypothesized that the loss of resistance is likely due to the instability of the RB proteins in the tubers. Regardless, the presence of the transgene did not affect tuber size and yield.

 The paper is available at http://apsjournals.apsnet.org/doi/abs/10.1094/PDIS-92-3-0339