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A-F = female; G,H = male
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.
Esophageal glands with 3 nuclei.
Hemizonion about 5 annules posterior to pore, caudalid about 8 annules anterior to anus.
Intestine overlapping rectum and usually extending into tail.
Tail rounded, with 10-16 annules.
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.
Widely distributed in the U.S., especially on woody or graminaceous plants.
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 root cortex of cotton, nematode prefers 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
Cotton, pine, oak, sycamore, wheat, carnation, cranberry, grasses, sugarcane, clover, vetch, grape, peach; highly pathogenic on turfgrass in Florida.
For an extensive list of host plant species and their susceptibility, copy the name
select Nemabase and paste the name in the Genus and species box
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).
Hoplolaimus galeatus damage (right) to roots of St. Augustine's grass (University of Florida photograph).
Note loss of feeder roots.
Infected cotton plants grown under conditions of limited moisture are susceptible to stunting, yellowing, and defoliation.
In cotton, the nematode feeds primarily endoparasitically causing considerable cortical damage during penetration.
Infected pine seedlings are devoid of healthy lateral roots and mycorrhizae. High nematode population levels can reduce root weight of Pinus clausa by 54% (Ruehle, 1972). Pine seedlings can suffer 50% mortality.
In sycamore, high inoculum levels caused extensive root necrosis and marked decrease in fresh weight.
After 75 days, peach seedlings growing in soil infected with Fusarium oxysporum and H. galeatus were markedly smaller than controls or combinations of fungus and other nematode species tested (Wehunt & Weaver, 1972).
Hoplolaimus galeatus damage on St. Augustine's grass (University of Florida photograph)
Hoplolaimus galeatus damage on Bermuda grass (University of Florida photograph)
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 a list of plant species or cultivars (if any) reported to be immune or to have some level of resistance to this nematode species, copy the name
select Nemabase Resistance Search and paste the name in the Genus and species box
CIH Descriptions of Plant-parasitic Nematodes, Set 2, No. 24 (1973)]