North Dakota State University Extension Service has declared a potato psyllid alert in North Dakota and Minnesota potato fields. The pests have been spotted in western and central North Dakota, though the populations have not yet become widespread.
Potato psyllid is the vector for the Liberibacter bacterium that causes Zebra Chip. But psyllids that are not infectious with Zebra Chip Liberibacter can damage potatoes. When they feed, they inject toxins, causing purple leaves, reduced tuber number and size, malformed tubers and chaining tubers.
The most impact can occur when plants have been infected before the tuber set.
To find psyllids, use a sweep net, sticky traps or leaf samples. Sticky traps should be placed at the edge of a field and monitors colonizing adults. If they're found in a field, the Extension recommends using an effective foliar insecticide.
For more information, visit ag.ndsu.edu.