Farmers, Gardeners can Help Root Out a New Nematode that Spreads Aggressively in Vegetable Crops

How can you help stop a plant pest?

As they check their fields and gardens this summer, growers are the first line of defense in preventing the spread of a microscopic worm threatening vegetable crops in the Southeast, including sweet potatoes.

The guava root-knot nematode — Meloidogyne enterolobii or M.e., for short — spreads aggressively and causes more severe damage than other nematode species, says Paula Agudelo, a Clemson University expert on plant diseases and their management. M.e. causes abnormal root growth, creating galls on root crops such as sweet potatoes, and it can infect many other crops, including watermelon, tomato, pepper, carrot, squash, cucumber, soybean, cotton and tobacco.

“M.e. can cause big crop losses and pose a risk to exports,” Agudelo says. “It is critical for commercial growers and home gardeners to learn what M.e. looks like so that they can prevent and manage the problem.”

M.e. has been found in 13 counties in North Carolina and one in South Carolina since 2019, triggering quarantines and regulations on out-of-state shipments of sweet potato seed and slips. South Carolina, Florida and Puerto Rico have confirmed cases, and monitoring is underway in Louisiana and Georgia, though it hasn’t been found there yet.

Clemson University is part of a multistate FINDMe team, along with scientists from North Carolina State University, the University of Florida, the University of Georgia, and the U.S. Department of Agriculture’s Agricultural Research Service. The U.S. SweetPotato Council, South Carolina Watermelon Association, and Georgia Fruit and Vegetable Growers Association are partners.