Hoplolaimus galeatus

 

Contents

 

Rev 06/13/2022

Lance Nematode  Classification Hosts
Morphology and Anatomy Life Cycle
Return to Hoplolaimus Menu Economic Importance Damage
Distribution Management
Return to Hoplolaimidae Menu Feeding  References
    Go to Nemaplex Main Menu   Go to Dictionary of Terminology


   


Classification:

        Tylenchina
        Tylenchoidea
         Hoplolaimidae
          Hoplolaiminae

     Hoplolaimus galeatus (Cobb, 1913) Thorne, 1935 

    Synonyms:
      Nemonchus galeatus Cobb, 1913
      Hoplolaimus coronatus Cobb, 1923
      Hoplolaimus tylenchiformis Andrassy, 1958
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Morphology and Anatomy:


A-F = female; G,H = male
Anterior region of (A) H. magnistylus, (B) H. galeatus, (C) H. concvaudajuvencus, (D) H. stephanus
Photomicrographs from Holguin et al (2015).

Female:

  • Cephalic region offset usually with 5 annules, forming an low cone generally with flattened sides.  Basal annule with 32-36 longitudinal striations seen in face view.  Cephalic framework yellowish, massive, differing in details between sexes.  

  • Stylet knobs with anteriorly directed processes; tulip-shaped..  

  • Esophageal glands with 3 nuclei.  

  • Hemizonid about 2 annules long, situated just anterior to excretory pore which is near level of esophago-intestinal valve.  

  • Hemizonion about 5 annules posterior to pore, caudalid about 8 annules anterior to anus.  

  • Ovaries outstretched, spermathecae round to oval.  Epiptygma single or double, usually conspicuous.  

  • Intestine overlapping rectum and usually extending into tail. 

  • Tail rounded, with 10-16 annules.  

  • Lateral field with 4 incisures, usually areolated, but occasionally only partly so.

Male:

  • Cephalic region higher and less conoid than female, hemispherical with convex sides.  Similar to female in other respects.

  • Spicules 40-52 µm long, slightly arcuate. 

  • Gubernaculum with titillae; gubernaculum may be bent distally in some specimens.  


[Ref: CIH Descriptions of Plant-parasitic Nematodes, Set 2, No. 24 (1973)]

 

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

 

 
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Distribution:

Widely distributed in the U.S., especially on woody or graminaceous plants.

Hoplolaimus galeatud may be spread over long- and short-distance spread is through movement of nematode-contaminated soil, infected transplants or nursery stock, run-off and irrigation water, cultivation tools, and equipment, and any human activity that can move soils from infested to noninfested sites (Chitambar et al., 2018).

 

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Economic Importance:

A-rated pest in California, USA.

 

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Feeding:

Primarily endoparasites.  Often the anterior end, or sometimes its entire body, is embedded in roots.inside the roots. Dead outer layers of roots may be sloughed off. layers to slough away.

Feeding occurs in root cortex of both lateral and mycorrhizal short roots, where the nematode causes considerable damage in its migration parallel to the long axis.  

In roots of cotton, nematode prefers feeding in phloem.

Damage to vascular tissue is more extensive than to cortex, abnormal division of phloem parenchyma or tylose production in the xylem sometimes occurring in response.

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Hosts:

Huge and varied host range, including cotton, pine, oak, sycamore, wheat, carnation, cranberry, grasses, sugarcane, clover, vetch, grape, peach; highly pathogenic on turfgrass in Florida.

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

Few aspects of biology and life-history have been investigated.  

Population increase has been studied on cotton (Krusberg & Sasser, 1956), cranberry (Bird & Jenkins, 1964), and bermuda grass (Di Edwardo, 1963).

Population dynamics has been investigated in other grasses and legumes (McGlohon et al., 1961), red pine seedbeds following chemical treatment (Sutherland & Adams, 1966), and cotton following Paspalum notatum (Rodriguez-Kabana & Pearson, 1972).

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Damage:

Hoplolaimus galeatus damage (right) to roots of St. Augustine's grass (University of Florida photograph).

Note loss of feeder roots.

Hoplolaimus galeatus damage on St. Augustine's grass (University of Florida photograph)

Hoplolaimus galeatus damage on Bermuda grass (University of Florida photograph)

In general, damage from root feeding in grasses may appear as yellowing, dead, or unproductive grass areas. Drought or nutrient deficitcan look similar and will exacerbate the damage effect.. A comprehensive examination of the roots of a lance nematode-infested lawns will typically reveal extensive root damage. Root tips appear to be dead, and there is an absence of small feeder roots (Crow and Branner, 2001; Scheck, 2022)..

 

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Management:

Fumigants - pre-plant treatment of plant rows with 1,3-Dichloropropene (1,3-D) produced taller pine trees after 5 years than trees growing in untreated rows.  

Treatment with Nemacur gave 3 months' field control on bermuda grass.  

Population can be reduced, but not eliminated, if infested soils are left fallow for 16 months.

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:

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.

CIH Descriptions of Plant-parasitic Nematodes, Set 2, No. 24 (1973).

Crow, W. T. and Brammer, A. S. 2001. Featured Creatures: Lance Nematode. FDA CS/DPI

Holguin, C.M., J.A. Baeza. J.D. Mueller and P. Agudelo. 2015.  High genetic diversity and geographic subdivision of three lance nematode species (Hoplolaimus spp.) in the United States. Ecology and Evolution (2015) 2929-2944.

H. Ferris

Scheck, H.J. 2022. California Pest Rating Proposal for Hoplolaimus galeatus (Cobb, 1913) Filipjev & Schuurmans Stekh Lance nematode. CDFA Sacramento, California, USA.

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Copyright © 1999 by Howard Ferris.
Revised: June 13, 2022.