Primary Resources: Florida DPI Circulars (pest alerts), CIH datasheets, CAB Crop Protection Compendium, CAB data base, EPPO Fact Sheets, regulatory lists from other countries (Asian countries in particular), an outdated APHIS list of nematodes of regulatory significance, a list of foreign nematodes prepared by Zafar Handoo, and the expertise of nematologists in the Working Group with representative experience from different regions of the USA and also from South America, Europe, and Asia.

Key selection and ranking criteria: absence from or limited distribution of the nematode in the US; known economic damage caused by the nematode; host range; and the distribution and economic importance of the nematode’s hosts in the US.  Secondary factors considered are: introduction potential and impact on exports.  It was decided that introduction potential should be of secondary importance because pathways can change over time.  Introduction and establishment potential would need to be investigated further in a complete pest risk assessment (PRA) completed by APHIS. The selections and rankings done by the group are based on the assumption that present regulations stay in place (e.g., regulating the entry of soil). 

Note The rankings for nematodes on the list (high, moderate, and low) are suggested guidelines or priority ratings for APHIS to develop a timeframe for conducting complete pest risk assessments (PRA). A low priority ranking should not be interpreted as being equivalent to a low risk for US agriculture or that minimal effort should be made to exclude these nematodes. Complete pest risk assessments are needed for all of the nematodes on the list, but this task requires resources and time beyond the scope of the current project. About one fourth of the candidate nematodes suggested for the list were given a very low priority ranking based on the Working Group consensus that either there are few pathways for their introduction into the US or because currently there is limited evidence that these nematodes damage economically important crops. By group consensus these nematodes (Table 3) were not included on the list.