Nematodes are the most numerous multi-cellular animals on earth. A few harm plants, and WSU researchers are working with Washington growers on naturally produced chemicals to control these nematodes.
N.A. Cobb, the father of modern nematology, wrote in 1915: “If all the matter in the universe except the nematodes were swept away, our world would still be dimly recognizable, and if, as disembodied spirits, we could then investigate it, we should find its mountains, hills, vales, rivers, lakes and oceans represented by a film of nematodes.”
Plant-parasitic nematodes cause economic losses to the agricultural industry locally and worldwide. It is estimated that plant-parasitic nematodes are responsible for losses of approximately $80 billion annually.
Nematodes also can cause export and quarantine issues with serious economic implications to agriculture.

Ekaterini Riga

Assistant professor and extension nematologist Ekaterini Riga, WSU Prosser, and her research team are developing long-term solutions to manage plant-parasitic nematodes that will benefit the agricultural industry without negatively affecting the environment.
“Only a small percentage of all nematodes are plant-parasitic and harmful,” Riga explained. “Most nematodes are considered beneficial to soil and plant health, but their biology and roles are not well understood yet.”
Riga’s team is using naturally produced chemicals from plants and other organisms to control plant-parasitic nematodes.
Chemicals produced from Brassica plants, such as mustards, are called biofumigants and are able to control parasitic nematodes with minimal impact on the beneficial free-living nematodes and environment. Brassica-produced biofumigants can reduce plant-parasitic nematodes in a wide range of vegetable and small-berry fruit crops, including wine grapes.
“The partnerships WSU has with the wine grape and vegetable industries are vitally important to our program’s efforts,” said Riga. “We are constantly testing new methods to find sustainable pest solutions that will benefit our state’s agricultural economy.”