Late Blight: Centuries-Old Pathogen with Deadly Impacts

Web Adminpotato, Research, Tomatoes, Top Posts

Late blight is a deadly, chronic pathogen that occurs annually in potato and tomato crops. Pam Roberts, a professor of plant pathology at the University of Florida, dubbed it a “disease of distinction” during her presentation at the 2018 Citrus Expo.

According to Roberts, there is a variety of factors that can contribute to a late blight infection. Once a plant is infected, the results can be detrimental if the disease goes untreated.

Late blight has occurred worldwide throughout history.  In fact, it was a key player in the Irish Potato Famine, which contributed to mass starvation in Ireland. There are many unanswered questions about this disease, even though it has been around for centuries.

Roberts says that researchers have been looking toward genotyping to answer some questions about late blight. “If we know the population through genotyping, it gives us a clue about which host it likes, and it gives us a clue to insensitivity or resistance to certain fungicides,” she says.

Researchers are able to sense aggressiveness through genotyping as well. “Some of the genotypes we saw in 2005 were very aggressive and difficult to control. If we saw that one pop up again, then we could put out an alert,” she explains.

In terms of management, Roberts says commercial growers have seen a lot of improvement in their choices of fungicides. “They’re highly effective and very good,” she says.

Roberts adds that growers may see some new tomato varieties that are resistant to the disease coming down the pipeline soon. “Host resistance is the most effective control method,” she explained.

Decision support systems can aid growers in coming up with management methods in their production systems, Roberts says. Cornell developed a decision support system for late blight that helps with fungicide timing for the most effective control.

Hear more from Roberts:

For more information on late blight, click here to view Roberts’ Citrus Expo presentation.

About the Author

Dan Cooper

Share this Post