NCDA&CS Quarantine Guava Knot Nematode

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NCDA&CS declares an internal quarantine for all North Carolina

counties for the Guava knot nematode

RALEIGH — The North Carolina Department of Agriculture and Consumer Services has established an interior quarantine for all 100 counties for the Guava root knot nematode, Meloidogyne enterolobii. Under the quarantine, regulated articles are prohibited from movement to non-quarantined states unless they meet the conditions specifically outlined in the official declaration. The quarantine is effective immediately and does not affect the movement of fresh market potatoes.

Currently, the only other state where Guava root knot nematode is known to occur is Florida. This nematode has been reported from China, Vietnam, Mexico, Brazil, Switzerland, Kenya, and Nigeria.

Guava root knot nematode is a serious pest of sweet potatoes, and can also infect cotton, soybeans, tobacco, potatoes, tomatoes, peppers, watermelons and other agricultural crops. It is unknown how the Guava root knot nematode entered the US, however it has been identified in eight North Carolina counties. The pest impacts both crop quality and yield, and damage is similar to other root knot nematodes (Meloidogyne spp.) which are the most common and destructive plant-parasitic nematode group worldwide, according to Dr. Weimin Ye, nematode assay section chief of the NCDA&CS’s Agronomic Services Division.

Regulated articles include:

  • The Guava root knot nematode, Meloidogyne enterolobii, in any living stage of development;
  • Sweet potato seed or sweet potato plants with or without roots produced in the state;
  • Soil and equipment determined to pose a risk of moving Meloidogyne enterolobii outside the quarantine area;
  • Any article, product, or means of conveyance when it is determined by the Plant Pest administrator to present a risk of spread of Meloidogyne enterolobii.

Soil and root samples can be tested for Guava root knot nematode through the NCDA&CS Agronomic Services Division. This pest is moved through soil and infested roots. Sanitation is key to preventing the spread of this pest and can be achieved by removing all soil from tractors, equipment, shoes, etc. with hot water (<176°F) when moving from field to field.

For questions regarding this quarantine, contact Joy Goforth, plant pest administrator at 919-707-3753 or