Unsegmented roundworms

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• Unsegmented roundworms
• Long slender
• Microscopic size .08mm to 7m
• Different kinds
• Most are beneficial, feeding on bacteria, fungi,
  or other microscopic organisms.
  
• Some are used as biological control organisms to
  help manage insect pests.
  
• There are also a group that feed on plants called
  plant-parasitic.
  
• Life Cycle Egg-L1-L2-L3-L4-Adult

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How Plant-Parasitic Nematodes Damage Plants

• As they feed
• They damage the root system.
• Reduce the ability for the plant to obtain water
  nutrients from the soil.
  
• They do the damaging with a stylet that acts like
  a needle.

Tomato Plant damaged by Nematodes
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Testing To See How Many Nematodes Are In The Soil

• 100cc soil of sample -Samples from Logan Oklahoma
  
  
• Southeast 2 lesion (Pratylenchus), 2 stunt
  (Tylenchorhynchus)
  
• Southwest 1 spiral (Helicotylenchus)
• Northwest 108 lesion
• Northeast 22 lesion, 6 dagger (Xiphinema)
• Arena 0

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Nematode Specialist

• Dr.Terry Wheeler
• Professor Nematology
• Works at Texas Agriculture Experiment Station in
  Lubbock, TX
  
• Came to Greta Schuster's Soil Water
  Conservation class
  
• Taught the class did a lab on nematodes
• Found out to have the test run it would be a 12
  fee for each soil sample
  
• Best time to test for nematodes are in the fall
• We had ours samples tested in the spring, so that
  is why our numbers where low
  

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Facts About Nematodes

• 100cc of soil may contain several thousands.
• Most soil nematodes are beneficial in the
  decomposition of organic matter.
  
• Most inhabit the thin film of moisture around the
  soil particles.
  
• The rhizosphere soil around small plant roots
  root hairs are particularly rich habitat for many
  kinds.
  

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Pratylenchus (lesion)(PRAT)-uh-LENK-us

• Greek pratum, a meadow, tylos, a knob on a club,
  enchos, a spear.
  
• Root-lesion nematodes - due to the entry into the
  plant root.
  
• 7 different species from New Zealand
• Nearly 400 plant species

• Create holes into the root cells crawl inside.
• Weak shallow root system with dead areas.
• Economic importance yes damage a wide range
  of plants.
  

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Pratylenchus Life Cycle

• Migratory endoparasites
• are motile nematodes which may feed on external
  surfaces of roots but generally burrow into the
  root to feed on internal root cells
  
• Vary from 1-2 months

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Tylenchorhynchus (Stunt)Tie-LENK-oh-Rink-us

• Greek tylos, a knob on a club, enchos, a spear,
  rhynchos, a beak or snout
  
• Stunt nematode reduction on host vigour their
  feeding causes
  
• 267 species
• Economic importance - minor

• Climate temperate to subtropical
• Feed mainly on surface tissue migratory
  ectoparsite
  
• Feed for short periods of time
• Causes reduced growth discoloration

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Tylenchorhynchus Life Cycle

• Migratory ectoparasites
• are motile (able to move by themselves)
  nematodes, which feed on the external surface
  cells of roots
  
• 31-38 day (egg-egg)

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You Are My Soil
You are my soil My only soil You keep me vital
night and day This much I know, friend you do
support me please dont erode my lifes soil away
.
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Helicotylenchus (Spiral) (HEE)-lih-koe-tie-LENK-u
s

• Greek helikos anything twisted or wound, tylos, a
  knob on a club, enchos, a spear
  
• Spiral nematode due to the form the heat killed
  nematode takes
  
• Damage to plants extensive
• 12 species from New Zealand

• Climate temperate to tropical
• Economic importance is limited but wide host
  range
  

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Helicotylenchus Life Cycle

• Migratory Ectoparasites
• Average cycle is 30-45 days

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Xiphinema (Dagger)(ZIFF)-uh-NEEM-uh

• Greek xiphos, sword, nema, thread
• Dagger nematodes due to the shape length of
  their stylet
  
• There are more than 50 species
• Economic importance - they can cause damage to a
  rage of plants can transmit plant viruses
  

• Feeds at or near the root tips
• Cessation of root growth caused by less than 12
  hours of feeding
  
• Cause slight gall necrosis

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Xiphinema Life cycle

• Migratory ectoparasites
• Very long life cycle several months to 2 years

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Management Strategies

• Host Planting Resistance
• Solarization heat from the sun
• Chemicals no nematicides labeled for use in a
  home gardens
  
• Flooding only with a hard-pan or clay layer
• Organic Matter (compost, manure, etc.) can
  prevent nematode damage
  
• Planting nematode activities slows when
  temperatures drop, so plant during cool months.
  

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Works Cited

• http//www.cals.ncsu.edu8050/pgg/dan_webpage/Nema
  todes
  
• http//creatures.ifas.ufl.edu/nematode/soil.htm
• http//edis.ifas.ufl.edu/BODY_NG005
• http//www.inra.fr/Internet/produits/HYPPZ/RAVAGEU
  R/6prapon.htmcyc
  
• http//ltpwww.gsfc.nasa.gov/globe/songs/songs.htm
  
• http//www.lucidcentral.com/keys/nematodes/html
• http//mgd.nacse.org/hyperSQL/squiggles/nematodes1
  .html
  
• http//mgd.nacse.org/hyperSQL/squiggles/other/prat
  levels2.htm
  
• http//mint.ippc.orst.edu/nemacylclehtm