Guava Root Knot Nematode

The resurgence of a pest, Guava root knot nematode (GRKN), known a few years ago to only occur in Florida and North Carolina (NC), has resulted in impacts to South Carolina (SC) nursery stock and sweet potato imports and exports.  GRKN was detected in Darlington County fields during a routine survey by Clemson University’s Department of Plant Industry (DPI) in September 2017.

The following shows how each state has responded to this resurgence and how it impacts exports and imports in South Carolina:

  • North Carolina – internally quarantined the entire state of NC.  Sweet potato planting stock is not allowed to be exported from NC without inspection, sampling, and certification for freedom from GRKN.  Impacts to SC growers might include a reduction in available sweet potato planting stock and an increase in the cost of this planting stock.

  • Louisiana – externally quarantined the entire state of SC.  Their quarantine includes prohibition of imports of fresh market sweet potatoes and sweet potato seeds and slips from SC. Further restrictions impact nursery stock, soil, and equipment movement from the entire state of SC. All SC nursery stock or equipment entering the state of Louisiana must have a DPI-issued certificate indicating the sample is free of GRKN.

  • Mississippi – externally quarantined Darlington County, SC. Their quarantine includes regulation of sweet potatoes and sweet potato seeds and slips from SC. Further restrictions impact nursery stock, soil, and equipment movement from the entire state of SC. All SC nursery stock or equipment entering the state of Mississippi must have a DPI-issued certificate indicating the sample is free of GRKN.  

  • Arkansas – externally quarantined Darlington County, SC.  Their quarantine includes regulation of sweet potatoes and sweet potato seeds and slips from SC. Further restrictions impact nursery stock, soil, and equipment movement from the entire state of SC. All SC nursery stock or equipment entering the state of Arkansas must have a DPI-issued certificate indicating the sample is free of GRKN.

This page is routinely updated as states alter and/or add quarantines for GRKN. Please check back often for quarantine changes.