Tylenchus		Contents		Rev 12/21/2024
		Classification		Hosts
		Morphology and Anatomy		Life Cycle
Return to Tylenchus Menu		Economic Importance		Damage
		Distribution		Management
Return to Tylenchidae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

 

   Chromadorea
       Rhabditida
       Tylenchina
        Tylenchoidea 

Tylenchidae 

Aerotylenchus (Fotedar & Handoo, 1979) [Areotylenchus in Fortuner, 1984] 

Etymology:

• From the Greek: tylos = knob, enchos = spear

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Morphology and Anatomy:

Members of the genus Tylenchus re characterized by having a striated lip region, vulva situated far back posterior to the mid body with the anterior ovary outstretched and post uterine branch short with elongate to filiform tails. The stylet is well developed with strong developed basal knobs (Thorne, 1962).

Key to the genera of the family Tylenchidae

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Distribution:

Commonly occurring in most soils. Feed on algae, mosses, lichens and plant roots. As an example: Soil nematodes were studied in three spruce forests in the Czech Republic from 1988 to 1991. A total of 74 species occurred, most belonged to the orders Tylenchida, Rhabditida and Dorylaimida. The most abundant nematodes were the mycophytophagous species of the family Tylenchidae followed by bacteriophages, especially by those in the order Rhabditida.

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Economic Importance:

Probably fairly small. Most reports are about occurrence and abundance rather than documenting any effects on growth. 

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Feeding:

Ectoparasites of plant roots, root hairs, algae, etc. 

Most species of the genus are algal, fungal, and moss feeders (Yeates et al., 1993) or associated with grasses, shrubs, and tree roots (Yeates et al., 1993; Ciobanu et al., 2003; Kantor et al., 2023).

Yeates et al. (1993a) described Tylenchus as plant feeders (algal, lichen (algal or fungal component), or moss feeders that feed by piercing), or hyphal feeders.

Yeates et al. (1993b):  classified Tylenchus spp. as "plant associated", indicating that they were found in the rhizospheres of plants.

Wood (1973) observed seceral Tylenchus spp. feeding and reproducing on fungi in tissue culture, but not on seedling roots.

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Hosts:

• Ferris et al. (1996):  Tylenchus davainei could not be cultured on the fungus Rhizoctonia.
•  Gowen (1970):  Tylenchus emarginatus ( = Cephalenchus emarginatus) fed and reproduced on sitka spruce seedlings growing in water agar without obviously damaging them.
•  Micoletzky (1925):  Tylenchus spp. more or less regularly feed on algae.
•  Sutherland (1967):  Tylenchus emarginatus ( = Cephalenchus emarginatus) fed and reproduced as a migratory ectoparasite on the roots of seven species of conifer (Picea abies, P. glauca, P. mariana, P. rubens, Pinus banksiana, P. sylvestris, P. resinosa), but the nematode was unable to feed or reproduce on ten species of soil-borne fungi (Cylindrocarpon radicicola, Cylindrocladium scoparium, Rhizoctonia solani, Trichoderma lignorum, Zygorhynchus moelleri, Chaetomium sp., Fusarium sp., Pestolotia sp., Pythium sp., Sporobolomyces sp.).
• Thorne (1961):  Tylenchus spp. frequently are among the most numerous nemas found in soil from the rhizosphere of plants. However, they have not been observed as either ectoparasites or endoparasites. Their small, strong spears indicate they probaly feed on either root hairs or fungal mycelia.  
• Wood (1971):  Tylenchus maiakus (nomen nuda) was observed feeding and reproducing on seedlings.  Tylenchus rikus (nomen nuda) was observed feeding and reproducing on fungi.  Tylenchus sp. was observed feeding on fungi and mosses.

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Life Cycle:

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Damage:

Relatively slight, small stylets penetrating only thin cell walls.

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Management:

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References:

Ferris, H., Venette, R.C., Lau, S.S. (1996), Dynamics of nematode communities in tomatoes grown in convential and organic farming systems, and their impact on soil fertility, Applied Soil Ecology, 3, 161-175

Bert, W. and Geraert, E. 2000. Nematode species of the order Tylenchida, new to the Belgian nematofauna with additional morphological data. Belgian Journal of Zoology 130:47-57.

Ciobanu, M., Geraert, E., and Popovici, I. 2003. The genus Tylenchus Bastian, 1865 in Romania (Nematoda: Tylenchidae). Nematologia Mediterranea 31:47�54

Geraert & Raski (1987)  Rev. Nematol. 10(2):143-161.

Geraert, E. 2008. The Tylenchidae of the world: Identification of the family Tylenchidae (Nematoda). Ghent, Belgium: Academia Press.

Gowen, S.R. (1970), Observations on the fecundity and longevity of Tylenchus emarginatus on sitka spruce seedlings at different temperatures, Nematologica, 13, 267-272

Hanel, Ladislav. 1996. Comparison of soil nematode communities in three spruce forests Boubin Mount, Czech Republic. Biologia (Bratislava) 51. 

Kantor, M.R., Handoo, Z.A., Subbotin, S.A., Mowery, J.D., Hult, M.N., Rogers, S., Skantar, A.M. 2023. Molecular and morphological characterization of Tylenchus zeae n. sp. (Nematoda: Tylenchida) from Corn (Zea mays) in South Carolina. J. Nematology 55: | DOI: 10.2478/jofnem-2023-0003

Micoletzky, H. (1925), Die freilebenden Süsswasser- und Moornematoden Dänemarks nebst Anhang über Amöbesporidien und andere Parasiten bei freilebenen Nematoden, D. Kgl. Danske Vidensk. Selsk. Skrifter, Naurvidensk. og Mathem., ser 8, 10, 57-310

Sutherland, J.R. (1967), Parasitism of Tylenchus emarginatus on conifer seedling roots and some observations on the biology of the nematode, Nematologica, 13, 191-196

Thorne, G. (1961), Tylenchinae, chapter 5 in: Principles of Nematology, McGraw-Hill Book Company Inc., New York - Toronto - London, 553 pp.

Thorne, G., 1962. Principles of nematology. Soil Science 93(1):70

Wood, F.H. (1971), Studies on the biology of soil-dwelling nematodes from tussock grassland, Ph.D. thesis, University of Canterbury, New Zealand, 286 pp.

Wood, F.H. 1973. Nematode feeding relationships: Feeding relationships of soil-dwelling nematodes. Soil Riol. Biochem. 5: 593-601.

Yeates, G.W., Bongers, T., Goede, R.G.M. de, Freckman, D.W., Georgieva, S.S. (1993a), Feeding habits in soil nematode families and genera - an outline for soil ecologists, Journal of Nematology, 25 (3): 315-331

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Copyright © 1999 by Howard Ferris.
Revised: December 21, 2024.