Globodera pallida (Stone) Behrens
A significant nematode disease of potato crops
Click here for the enlargement of |
this photo or for
Name: Globodera pallida (Stone) Behrens
Animalia: Nematoda: Tylenchida: Heteroderidae
Common Names: potato cyst nematode; white potato cyst nematode; pale potato cyst nematode; nematodo quiste blanco de la papa; nématode blanc de la pomme de terre
The potato cyst nematodes, Globodera pallida and Globodera rostochiensis (the golden potato cyst nematode), are major pests of the potato crop in cool-temperate areas, and are recognized as two of the most difficult crop pests to control. They can be spread into new areas as cysts on seed potatoes, nursery stock, soil, flower bulbs, and potatoes.
Issues of Concern: Both species of potato cyst nematode are regulated externally and internally by NAPPO countries and, therefore, are of concern to NAPPO countries. Currently G. rostochiensis is present in isolated areas of Canada (Newfoundland, British Columbia), Mexico, and the U.S. (New York). In contrast, G. pallida is only present in Newfoundland, Canada in North America; therefore, it is a very important pest to keep out of the U.S., Mexico, and unaffected parts of Canada. Also, at present, G. pallida poses more risk because of the lack of commercially available potato cultivars having resistance to this species (Smith et. al, 1997).
Hosts: Confined to Solanaceae. The most important host are potatoes (Solanum spp.), followed by tomatoes (Lycopersicum esculentum) and eggplant (S. melogena).
Europe (Austria, Belgium, Bulgaria, Czech Republic, Cyprus, Faroe Islands, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, England, Wales, Northern Ireland, Scotland, UK Channel Islands), Asia (Cyprus, India, Pakistan), Africa (Algeria, Tunisia), North America (Newfoundland, Canada), Central America (Panama), South America (throughout the high Andean region, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela), Oceania (New Zealand).
Quarantines: G. pallida is of quarantine significance to NAPPO countries. Although the import of soil and potatoes is highly regulated, there is the risk of introduction of G. pallida through smuggling of soil and potatoes or in minute amounts of soil on many different plant and nonplant products entering the country. Introduction could also occur through contaminated soil with imported second-hand vehicles and used agricultural machinery and equipment.
Detection is by finding mature females and cysts, both of which are just visible to the naked eye as minute globular structures (200-500 µm, smaller than a pinhead). Mature females are a white to slightly cream color and are found attached to the root surface (Unlike the mature female of G. rostochiensis, the female of G. pallida does not go through a yellow colored phase). When the females die their skin hardens and turns brown to become a protective cover (cyst) around the eggs inside. The brown cysts can be found attached to the root surface (at the flowering stage of the plant), in soil, or embedded in tubers. When examining plant roots, the soil must be carefully removed as the females and cysts can be readily dislodged. Collect soil clinging to plant material by cutting off dirty roots or the base of bulbs. When soil is not apparent, tap or knock surface dust onto clean paper. Inspection stations can wash plant material over screens without cutting. Extraction of cysts from soil is also recommended. Be alert for soil with nonplant cargoes.
Of note: Each cyst contains on average 500 eggs, and cysts can remain viable for up to 30 years in the absence of any hosts.
Source: Division of Plant Industry, Florida Department of Agriculture; USDA-ARS
Smith, I.M., McNamara, D.G., Scott, P.R., and Holderness, M. (Eds.). 1997. Quarantine Pests for Europe, Second Edition. CAB International, Wallingford, U.K. (in association with EPPO).
USDA-ARS Nematology Lab website
CFIA/ACIA Pest Data Sheet
University of Nebraska-Lincoln Nematology website
INRA Pest Data Sheet
Comité de Sanidad Vegetal del Cono Sur - COSAVE Pest Data Sheet
Warning: The information in this archived item was not confirmed with the appropriate National Plant Protection Organization and is provided solely for informational purposes. Please use this information with caution.