Pale cyst nematode - Globodera pallida
Effective: August 18, 2010
Taxonomic Position: Tylenchida : Heteroderidae
Pest Type: Nematodes
Pest Code (NAPIS): NEFBBBC
This pest is a member of the following surveys: Cyst Nematode, Solanaceous Hosts
These Approved Methods are appropriate for: 2024, 2023, 2022, 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011
Survey
Approved Method(s)
Method |
Detail |
NAPIS Survey Method |
Soil Sample |
Send sample to nematology diagnostic lab where nematodes will be extracted and identified (preferred method). |
3012 - General Soil Sample |
Tissue Sample |
Send sample to nematology diagnostic lab where nematodes will be extracted and identified. |
3011 - General Tissue Sample |
Method Notes: Laboratory methods that are acceptable for cyst extraction include sugar centrifugation, USDA cyst extractor, Fenwick can sieving, wet sieving, and elutriation.
Survey Recommendations
The following are recommendations for executing the survey using the approved methods for pest surveillance. The recommendations are developed through literature review and consultation with subject matter experts.
Signs: Mature females and cysts are just visible to the naked eye and can be seen as minute white globes on the root surface.
At the appropriate stage of development, females are prolonged white (slightly cream but no yellow phase) (compare to G. rostochiensis).
Symptoms: Patches of poor growth, chlorosis, and wilting with poor top growth may be seen. Affected plants suffer yield loss, and tubers are smaller.
Key Diagnostic or Identification
Approved Method(s)
ID/Diagnostic: Morphological: Characteristics of second-stage juveniles, females, and cysts (Baldwin and Mundo-Ocampo, 1991).
Molecular: Immunological, protein, and DNA-based techniques are available. RAPD and RFLP analyses are also available.
There are PPQ CPHST-validated conventional PCR (Skantar et al., 2007) and real-time PCR methods available to detect G. pallida, G. rostochiensis, and G. tabacum (Nakhla et al., 2008).
A real-time PCR has been developed by Nakhla et al. (2010) that shortens the time needed. A validated work instruction is available.
Mistaken Identities: Other Globodera species, particularly Globodera rostochiensis and G. tabacum.
In Progress / Literature-based Diagnostics: A multiplex PCR was developed to distinguish G. pallida and G. rostochiensis (Pylypenko et al., 2005).
Madani et al. (2005) developed a real-time PCR assay that will rapidly detect and quantify G. pallida and Heterodera schachtii (beet cyst nematode).
Madani et al. (2008) developed a multiplex real-time PCR that can distinguish G. pallida, G. rostochiensis, and G. tabacum.
Notes: All three species of Globodera (pallida, rostochiensis, and tabacum) occur in the United States. G. pallida is present in Idaho.
Protocols for processing soil samples for PCN are available.
A synergistic relationship between Verticillium wilt (Verticillium dahliae) and G. pallida has been observed with some potato cultivars.
Contact Ashlee Barth for the most up-to-date work instructions.