Root-knot nematodes - Meloidogyne sp./spp.
EEffective: April 11, 2011 - December 31, 2013
Taxonomic Position:
Tylenchida : Heteroderidae
Pest Type:
Nematodes
Pest Code (NAPIS):
NEOBCAA
No manual – See Host Matrix |
These Approved Methods are appropriate for:
Pest is vectored by:
This pest is is not known to be a vector and it is not vectored by any organism.
Survey
Approved Method(s):
Method |
Instructions |
NAPIS Survey Method |
Soil Sample |
Send sample to nematology diagnostic lab where nematodes will be extracted and identified. |
3012 - General Soil Sample
|
Tissue Sample |
Collect abnormally swollen roots and send to a nematology diagnostic lab where damage and galled roots will be assessed. |
3011 - General Tissue Sample
|
Signs:
Nematode egg masses are often visible on the surface of galls.
Symptoms:
Root-knot nematodes (RKNs) symptoms are similar to those caused by nutrient or water deficiency, including stunting, wilting, and chlorosis of leaves. Small root galls and lateral proliferation of roots is also observed with most species. For citrus RKNs, yellowing of leaves, premature flower drop, early ripening and fruit drop, and reduced fruit quality and yield are observed. Citrus roots infected by root-knot nematodes show swollen rot tips and axes.
Key Diagnostics
ID/Diagnostic: Morphological
Assessment of root galls will indicate a possible root knot nematode infection.
Morphological: The length of at least 20 second-stage juveniles, the head and stylet morphology of males, and the nature perineal patterns of females from samples.
Mistaken Identities:
Other Meloidogyne species (M. arenaria, M. hapla, M. incognita, and M. javanica)
Notes:
The occurrence of RKNs on weeds is common in citrus groves. Soil samples from these groves are often positive for root-knot nematode because they originate from weed hosts. Careful examination and separation of roots in the samples provides certainty of the origin of nematode infestation.