Tomatoes With Late Blight Resistance
Late blight was worse on Long Island, NY, in 2011 than it was in the notoriously difficult 2009 season, thanks to the wet weather. From a small source, the pathogen quickly spread throughout the region, causing a huge epidemic, says Meg McGrath, an associate professor in the department of Plant Pathology and Plant-Microbe Biology at Cornell University.
“Not knowing when and where late blight might occur and knowing by the time you see it, it often is too late to manage, makes it a very difficult disease,” says McGrath. “But now growers will be more informed as a result of monitoring, pathogen strain identification, and other activities of a new national project, http://usablight.org.”
To help growers in their fight against late blight on tomatoes, a couple of seed companies are now selling varieties that are resistant to the disease. “These varieties have excellent resistance to the current late blight strains,” says McGrath.
The varieties in question are marketed by Seedway and Johnny’s Selected Seeds. Seedway is currently distributing Mountain Magic, a Campari type, and Plum Regal. Produced by Bejo Seeds, both varieties were developed by Randy Gardner at North Carolina State University. The third tomato is a slicer called Defiant available from Johnny’s Selected Seeds.
In spite of the fact these varieties show a high level of resistance, McGrath adds that it is always a good idea to use an integrated management approach when combating late blight. “You don’t always know when the pathogen has changed,” she warned.