Meloidogyne partityla

Meloidogyne partityla	Contents	Rev 05/18/2026
Pecan Root-Knot Nematode	Classification	Hosts
	Morphology and Anatomy	Life Cycle
Return to Meloidogyne Menu	Economic Importance	Damage
	Distribution	Management
Return to Meloidogynidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

     Chromadorea
       Rhabditida
       Tylenchina
        Tylenchoidea
          Meloidogynidae
           Meloidogyninae

Meloidogyne partityla Kleynhans, 1986

Pecan Root-Knot Nematode

Review general characteristics of the genus Meloidogyne.

Morphology and Anatomy:

Female:

Male:

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Distribution:

Reported only from South Africa and USA. In USA it is reported from Texas, New Mexico, Arizona, Oklahoma and Florida, primarily on roots of pecan trees (Carya illinoinensis).

Economic Importance:

Pecan tree seedlings are stressed and grow poorly. Seedlings have dead shoots in canopy. Yield decline reported for mature trees in New Mexico.

A-rated pest in California Nematode Pest Rating System (Martin, 2026)

Feeding:

Sedentary endoparasite.

Feeding site establishment and development typical of genus.

Known hosts are pecan, Carya illinoensis, hickory, oak and walnut trees (Starr et al., 2006). Host range appears to be narrow, atypical for this genus. Besides pecan, hosts are mainly woody perennials: Carya ovata (shagbark hickory), Juglans regia (English walnut), J. hindsii (California black walnut), Quercus laurifolia (laurel oak), Q. nigra (water oak), and Q. stellata (post oak) (Kleynhans et al.,1986; Brito et al., 2016; Khanal et al., 2016).

Reported non-hosts include beans, peas, cowpea, tomato, peach and weeping lovegrass (Marais and Heyns, 1990).

For an extensive host range list for this species, click

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Life Cycle:

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters

Chromosome number 2n=40-42. The large number, and variability of chromosome number, are typical of species reproducing by obligate mitotic parthenogenesis. (Marais and Kruger, 1991; Triantaphyllou, 1985; Subbotin et al., 2021).

Sedentary endoparasites.

Female body ruptures root cortex and may protrude with the egg mass on the root surface.

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Damage:

Both major roots and young roots have prominent galling. Seedlings stressed with dead shoots (Brito et al., 2006; 2016)..

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Management:

Easily distributed and spread with infected root material. A two-year host free rotation is suggested for tree nurseries (Brito et al. 2006)..

The most likely method os intorduction of M. partityla to new areas is through the transportation of infested or contaminated planting materials. Nematodes can easily be carried by infested seedlings. Additionally, the movement of non-host plants intended for planting, like seedling transplants or nursery stock, as well as non-host plant products such as bulbs, tubers, corms, and rhizomes, can contribute to the spread of M. partityla if they are contaminated with soil infested by the nematodes. Also the nematode can be spread through the movement of bulk soil.

Within a field, the nematode can be sapread by irrigation and soil adhering to equipment (Chitambar et al., 2018; Martin, 2026).

Host Plant Resistance, Non-hosts and Crop Rotation alternatives:

For plants reported to have some level of resistance to this species, click

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References:

Brito, J.A., R. Kaur, D.W. Dickson, J.R. Rich and L.A. Halsey. 2006. The pecan root-knot nematode, Meloidogyne partityla Kleynhans, 1986. Nematology Circular 222. Florida Dept Ag. and Cons. Serv.

Brito, J.A., Smith, T.E., Achinelly, M.F., Monteiro, T.S.A. and Dickson, D.W., 2016. First report of Meloidogyne partityla infecting water oak (Quercus nigra) in Florida. Plant Disease, 100(6), p.1246.

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.

Khanal, C., Szalanski, A.L. and Robbins, R.T., 2016. First report of Meloidogyne partityla parasitizing pecan in Arkansas and confirmation of Quercus stellata as a host. Nematropica, 46(1), pp.1-7.

Kleynhans, K.P.N., 1986. Meloidogyne partityla sp. nov. from pecan nut [Carya illinoensis (Wangenh.) C. Kpch) in the Transvaal Lowveld (Nematoda: Meloidogynidae). Phytophylactica, 18(3), pp.103-106.

Marais, M. and J. Heyns. 1990. Host plant tests with Meloidogyne partityla Kleynhans, 1986. Phytophylactica 22:161-162.

Marais, M. and Kruger, J..C.de W. 1991. The cytogenetics of some South African root-knot nematodes (Heteroderidae: Nematoda). Phytophylactica 23:265-272.

Martin, H.J. 2026. California Pest Rating Proposal for Meloidogyne partityla Kleynhans, 1986 Pecan root-knot nematode. California Dapartment of Food and Agriculture, Sacramento, California, USA

Starr, J.L., E.K. Tomaszewski, M. Mundo-Ocampo and J.G. Baldwin, 1995. Meloidogyne partityla on pecan: isozyme phenotypes and other hosts. J. Nematology 28:565-568.

Subbotin, S.A. Palomares-Rius, J.E., Castillo, P. 2021. Systematics of Root-knot Nematodes (Nematoda: Meloidogynidae). Nematology Monographs and Perspectives Vol 14: D.J. Hunt and R.N. Perry (eds) Brill, Leiden, The Netherlands 857p.

Triantaphyllou, A.C. 1985. Gametogenesis and the chromosomes of Meloidogune nataliei: not typical of other root-knot nematodes. J. Nematology 17:1-5.

Triantaphyllou, A.C. 1985. Cytogenetics, cytotaxonomy and phylogeny of root-knot nematodes. In Sasser, J.N. & Carter, C.C. (eds) An Advanced Treatiswe on Meloidogyne.Vol 1. Biology and Control.N.C. State Universty Graphics, Raleigh, N.C. USA.