Rev 12/16/2024
Chromadorea Rhabditida Tylenchina Tylenchoidea Pratylenchidae Pratylenchinae
Pratylenchus crenatus Loof, 1960
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:
North America (California, Canada), Europe, Japan, South America (Brazil, Venezuela), South Africa.
C-rated pest in California Nematode Pest Rating System (Formerly D-rated based on inadequate consideration of biology and plant damage potential).(Scheck, 2023)
Migratory endoparasite. Feeds, reproduces, and moves intracellularly within root tissues; often in cortical cells. Feeds from neighboring cells as it migrates through tissues.
Wide host range; often found inceraeals and grasses.
Population levels of P. crenatus increased at different rates on wheat, maize, buckwheat, common rape, common persicaria, common agrimony, horseweed and soaproot. The best host was horseweed and the worst was wheat. Body size parameters of the nematode differed among hosts (Urek, 1999).
Turf (golf courses) in Ontario, Canada. Also from fruit trees in Canada (Yu, 2008).
Tobacco in Japan.
Corn.
Reproduction probably parthenogenic; males are rare (Karssen and Bolk, 2000). May complete the entire lifge cycle within root tisseues or migrate in and out of roots.can occur parthenogenically with only females. Six life stages are recognized, the egg, four juvenile stage and the adult (usually female adult). First-stage juveniles develop within the egg and molt to the second-stage juvenilerior to hatching Each stage transitions to the next via a molt of the cuticle. All post-hatch stages are vermiform, motile and feed on plant cells.
The life cycle may be 45-65 days and influenced by temperature, moisture and probably by plant host status..
Pratylenchus crenatus survives the winter in infected roots or soil as eggs, juveniles, or adults. During spring, when plant growth is active, eggs hatch to commence the life cycle within roots or in rhizosphere soil (Scheck, 2023).
Ecophysiological Parameters:
Lesion nematodes cause a variety of symptoms in plants, including stunted roots and reddish-brown or black lesions along the roots caused by cell death or host defence responses. These lesions may appear in small spots at the early stages of infection, but expand as the nematodes migrate within roots.
As the nematodes migrate from cell to cell within roots they feed on neighboring cells which causes cell breakdown and formation of cavities.
As with many root-damaging organisms, aboveground symptoms are very specific or diagnostic. Plants may appear stunted and chlorotic, nutrient deficient, lack vigor, have reduced tillering, reduced grain yield and grain quality (Chitambar et al., 2018). The Interaction of lesion nematodes with pathogenic soil-borne fungi, including Verticillium, Rhizoctonia, and Fusarium, can result in more severe disease complexes (Back et al., 2002)..
Host Plant Resistance, Non-hosts and Crop Rotation alternatives:
Avoid spread! Endoparasitic nematodes are easily spread in rooted planting m,aterial, either from nurseries or by sharing of rootings of ornamentals or woody seedlings between gardeners or landscape designers. They are easily moved and intorduced in contaminated soil, poorly sanitized farm equipment, contaminated planting stock, such as tubers or seedlings, nursery stock, such as bare root trees, and irrigation water. The spread of lesion nematodes within fields is often accelerated by tillage and other cultural practices that move and spread soil (Davis and MacGuidwin, 2000).
Back, M.A., Haydock, P.P.J. and Jenkinson, P., 2002. Disease complexes involving plant parasitic nematodes and soilborne pathogens. Plant Pathology, 51:683-697.
Chitambar, J. J., Westerdahl, B. B., and Subbotin, S. A. 2018. Plant Parasitic Nematodes in California Agriculture. In Subbotin, S., Chitambar J., (eds) Plant Parasitic Nematodes in Sustainable Agriculture of North America. Sustainability in Plant and Crop Protection. Springer, Cham.
Davis, E. L., and MacGuidwin, A. E. 2000. Lesion nematode disease. Plant Health Instructor DOI: 10.1094/PHI2000-1030-02.
Karssen, G. and Bolk, R.J., 2000. An additional character useful for the identification of Pratylenchus crenatus Loof, 1960 (Nematoda: Pratylenchidae). Nematology, 2:.695-697.
Klinkenberg, C.H. 1963. Observations On the Feeding Habits of Rotylenchus uniformis, Pratylenchus crenatus, P. penetrans, Tylenchorhynchus dubius and Hemicycliophora similis. Nematologica 9:502-506.
Loof, P. A. A. 1960. Taxonomic studies on the genus Pratylenchus (Nematoda). T. Pl. ziekten, 66: 29-90.
Scheck, H.J. 2023. California Pest Rating Proposal for Pratylenchus crenatus Loof 1960 Root lesion nematode: Current Pest Rating: D, Proposed Pest Rating: C. California Department of Food and Agriculture, Sacramento, California, USA.
Urek, G. 1999. The effect of host plants on the biopotential and the morphometric characteristics of Pratylenchus crenatus Loof, 1960. Acta Phytopathologica et Entomologica Hungarica. 34: 253-262.
Yu, Q. 2008. Species of Pratylenchus (Nematoda: Pratylenchidae) in Canada: description, distribution, and identification. Canadian J. Plant Pathology 30:477-485.