A U.S. Department of Agriculture entomologist is using itsy-bitsy forceps to dissect the potato psyllid to find out how it spreads the zebra chip bacterium to potatoes.

Rodney Cooper, who works for the Agricultural Research Service in Wapato, Wash., combines the microfine surgery with a fluorescent microscope to detect fluorescent genetic markers, according to a news release.

After dissecting a psyllid, Cooper subjects its organs and tissues to probes that glow green if the disease is present.

So far, he and his colleagues have observed Liberibacter in four main parts: the gut, hemolymph (similar to blood in insects), bacteriomes (organs where symbiotic bacteria live) and salivary glands.

The goal is to better understand how Liberibacter, the organism responsible for zebra chip, survives in the psyllid, from the time it ingests the bacterium from an infected plant to the time it injects it into a new plant.

The main disease-control method involves insecticides.

But researchers are seeking more sustainable approaches, such as disease-resistant varieties.

Knowledge gained from Cooper's studies also may help target the bacterium directly.

Zebra chip, which is harmless to humans and animals, gets its name from discoloration it causes inside tubers.

Liberibacter disrupts starch metabolism in the tuber, converting it into sugars.

When slices of the infected tuber are subjected to high heat, such as during frying of chips, it caramelizes and causes dark stripes.