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NOTES ON TAXONOMY AND BIOLOGY: This species differs from the golden nematode (Globodera rostochiensis) because females lack the golden phase. They are pale and have a smaller number of cuticular striae (8-20 vs. 16-31) in the perineum . This cyst forming nematode has sedentary endoparasitic habits. Cysts are persistent tanned sacs derived by the female body and contain the eggs. Cysts persist in soil for more than 10 years. Second-stage juveniles (J2) emerge from the cysts, penetrate host roots and establish a specialized feeding site (syncytium) in the stele. Adult swollen females retain the eggs, rupture root cortex and protrude from root surface. At the end of the reproductive phase, females die and become spherical brown cysts. These cysts are circumfenestrate and lack bullae.
GEOGRAPHICAL DISTRIBUTION: Reported from Algeria, Austria, Australia, Belgium, Bolivia Bulgaria, Canada, Chile, Colombia, Costa Rica, Cyprus, Ecuador, Egypt, Faeroe Island, Falkland Islands, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Lebanon, Luxemburg, Malta, Morocco, New Zealand, Norfolk Island, Norway, Pakistan, Panama, Peru, Philippines, Poland, Portugal, Romania, Sierra Leone, Spain, Sri Lanka Sweden, Switzerland, Tajikistan, The Netherlands, The Philippines, Tunisia, Turkey, Ukraine, UK, Venezuela, Yugoslavia. Globodera pallida does not occur in the USA.
HOSTS: Potato (Solanum tuberosum) is the major host. Other hosts include many Solanum species, oca (Oxalis tuberosa), jamestown-weed (Datura stramonium), tomato (Lycopersicon spp.), and Salpiglossis spp.
CROP LOSSES: Under poor nematode management, crop losses induced by G. pallida range 20-70% (Greco, 1988). Presence of potato cyst nematodes in potato producing areas for the international market is prohibited by many countries.
MEANS OF MOVEMENT AND DISPERSAL: Nematodes are dispersed with soil debris and plant material contaminated by the cysts and by infected potato tubers.
RATING: (H) Because of yield loss and adverse regulatory impact caused by this nematode, the risk posed by this pest to the United States is very high.
REFERENCES:
CAB International, 2001. Globodera rostochiensis,
in
Crop protection compendium, global module, 3rd edtion. CAB International:
Wallingford, UK.
Greco, N. 1988. Potato cyst nematodes: Globodera
rostochiensis and G. pallida. Nematology Circular No. 149, Florida
Department of Agriculture and Consuner Services, Division of Plant Industry,
Gainesville, FL, USA.
Marks R. J., and B. B. Brodie. 1998. Potato cyst
nematodes: Biology, distribution and control. Wallingford, UK: CAB International.
Stone, A. R. 1973. Heterodera pallida . CIH
descriptions of plant parasitic nematodes, Set 2, No. 17. St. Albans,
UK: Commonwealth Institute of Helminthology.