Hoplolaimus columbus
Contents
Rev 11/30/2012
Hoplolaimus columbus |
Contents |
Rev 11/30/2012 |
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| Columbia Lance Nematode |
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Classification |
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Hosts |
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Morphology and Anatomy |
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Life Cycle |
| Return to Hoplolaimus Menu |
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Economic Importance |
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Damage |
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Distribution |
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Management |
| Return to Hoplolaimidae Menu |
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Feeding |
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References |
| Go to Nemaplex Home Page |
Synonyms:
None.
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Adults are 0.75-1.0 mm long. Female:
Male:
[Ref: CIH Descriptions of Plant-parasitic Nematodes, Set 6, No. 81 (1976)]
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Hoplolaimus columbus has been reported from several different countries around the world, including infestations in Pakistan, India, and the United States. In the U.S., H. columbus is limited mainly to the southeastern part of the country, reported in North Carolina, South Carolina, Georgia, Alabama, and Louisiana. It is reported most frequently from the coastal plains of Georgia, North Carolina, and South Carolina. 50% of the cotton acreage of South Carolina is infested and, of that acreage, 38% is above threshold levels (greater than 500 per pint of soil). In sandy loam soils, on favorable hosts, it often replaces Meloidogyne incognita as the predominant species.
While the reports from Alabama and Louisiana are isolated, many experts anticipate H. columbus will continue to spread throughout the cotton belt.
Sandy and sandy loam soils seem to be the preferred habitat.
[Source: www.cottonexperts.com, Manual of Agricultural Nematology]
Hoplolaimus columbus causes significant damage to cotton and soybeans where it occurs in the southeastern US.
Hoplolaimus
columbus in cotton roots
Ecto- and endoparasitic on soybeans and cotton; causes discolored cortical cells in root maturation zone.
Does not penetrate endodermis in cotton, but does in some soybean varieties where it penetrates endodermis, pericycle, and phloem.
On cotton it feeds as a migratory endoparasite, penetrating the cortex but not the endodermis. H. columbus often feeds on the root tips of young cotton plants, altering root growth patterns.
[Source: “Plant Parasitic Nematodes Attacking Cotton in the United States”]
The two most important hosts in the United States are cotton and soybeans. Corn and wheat are also hosts, but the nematode is not yet reported from areas of intensive production of these crops.
Watermelons, cucumbers, okra, and cantaloupe are all poor hosts and tolerant of the nematode. In these cases the nematodes will survive on their roots, but yield is not affected.
Weed hosts include henbit, nutsedge, cowpeas, crimson clover, pigweed, sicklepod, and showy crotolaria.
Other hosts include sugarcane, bananas, lima beans, snap beans, bermudagrass, zoysia, millet, and St. Augustine grass.
[Source: http://pubs.caes.uga.edu, Plant Parasitic Nematodes of Subtropical and Tropical Agriculture]
For an extensive list of host plant species and their susceptibility, copy the name
Hoplolaimus columbus
select Nemabase and paste the name in the Genus and species box
Reproduction is by parthenogenesis and males are extremely rare.
The life cycle on cotton and soybeans is 45-49 days.
The diovarial reproductive system is fully developed after the fourth molt, and occupies about 61% of the body length.
H. columbus females deposit eggs individually, not in masses. However, 20-50 eggs may be deposited in a local area.
The nematode has a high capacity to survive adverse conditions and a very high overwintering rate. It can tolerate extremely high desiccation and osmotic stress.
All motile stages are infective.
H. columbus is reported to survive in dry soil for up to five years
[Ref: CIH Descriptions of Plant-parasitic Nematodes, Set 6, No. 81 (1976) and H. Ferris.]
Lewis, Smith, and Powell (1974) demonstrated pathogenicity on soybean and cotton. Astudillo & Birchfield (1980) observed that H. columbus was present throughout the roots of sugarcane, damaged parenchyma, caused cell necrosis, and resulted in coarse, depleted root systems. However, root and shoot weights and leaf lengths were not affected.
Infected soybeans are dwarfed, wilted, chlorotic and/or bear only a few pods.
In cotton, the nematode feeds on the root tips of young plants, altering root growth patterns. The taproot maybe stunted and secondary branching may increase in the upper four inches of soil. This restricts the uptake of water and nutrients causing stunting and mild chlorosis. Affected cotton plants show symptoms of nutrient deficiency, including purple leaves, shedding of squares, and small bolls.
The damage to cotton roots makes the plant very susceptible to Rhizoctonia solani.
The nematode also may cause lesions on roots and discolor cortical cells in the root maturation zone.
Populations increase to levels as high as 4,000 per 100cc soil.
[Nematode Pests of Crops]
Cultural Practices:
Crop rotations with non-host crops or non-host cover crops is effective.
Since there are many weed hosts and the nematode can survive in dry soil for several years, fallowing a field to reduce the pest may be ineffective.
A shallow hardpan often restricts roots to upper 6 inches of soil and reduces plant tolerance. Subsoiling and fumigation increases yield dramatically (Bird et al., 1974). Subsoiling and destruction of restrictive soil layers allows greater access to water and nutrients and can offset nematode damage.
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
Hoplolaimus columbus
select Nemabase Resistance Search and paste the name in the Genus and species box
Nematicides:
Fumigants are effective and can result in a 5-fold increase in yield of cotton. Nematicides such as Telone have been most effective way to decrease population levels.
[Source: Plant Nematodes and Their Control]
CIH Descriptions of Plant-parasitic Nematodes, Set 6, No. 81 (1976)
CIH Descriptions of Plant-parasitic Nematodes, Set 6, No. 81 (1976)
Bhatti et al, Nematode Pests of Crops, 1992. CBS Publishers, Bhola Nath Nagar, Shahdara
Decker, Heinz. Plant Nematodes and Their Control, 1981. Loglos Publishers, Moscow
Luc, Michel et al., Plant Parasitic Nematodes in Subtropical and Tropical Agriculture, Second Edition. 2005. CABI Publishing, Wllingford, UK
http://apsnet.org/pd/pdfs/2003/1208-01F.pdf. “Plant Parasitic Nematodes Attacking Cotton in the United States”, by Koenning et al. Visited Friday, November 26, 2005
http://plpnemweb.ucdavis.edu/nemaplex/nemaplex.htm. Nemaplex. Hoplolaimus columbus. Visited Monday, November 21, 2005
http://www.cottonexperts.com/=file:Industry%20News/1060992211903010d012553d26063229/file. Nematodes: A belt-wide Threat. Visited Friday, November 26, 2005
http://pubs.caes.uga.edu/caespubs/pubcd/B904.htm. Plant Susceptibility to Major Nematodes in Georgia. Visited Friday, November 26, 2005.
