PCA - Nematodes!!
List the major environmental/ecological factors that influence the time it takes a nematode to
complete its life cycle. - ✔✔Temperature, moisture, availability of food from the host.
Identify the host(s) of some non-plant parasitic nematodes. - ✔✔Animals, humans, insects
Ectoparasite - ✔✔Nematode that feeds on the outside of the plant.
Endoparasite - ✔✔Nematode that feeds on the inside of the plant.
List three ways ectoparasitic and endoparasitic species differ. - ✔✔Ectoparasites move to
different plants.
Endoparasites move inside the plant tissue.
Ectoparastites are sampled from the soil, endoparasites are sampled from the plant.
Identify by genus and common name the major ectoparasitic nematode groups. -
✔✔Xiphinema spp. - Dagger
Belonolaimus spp. - Sting
Trichodorus spp. - Stubby-root
Longidorus spp. - Needle
Paratylenchus spp. - Pin
Criconemoides & Mesocriconema spp. - Ring
Helicotylenchus & Rotylenchus spp. - Spiral
Tylenchorhynchus spp. - Stunt
Identify by genus and common name the major endoparasitic nematode groups. -
✔✔Meloidogyne spp. - Root-knot
,Heterodera & Globodera spp. - Cyst
Pratylenchus spp. - Lesion
Radopholus spp. - Burrowing
Rotylenchulus reniformis - reniform
List the two most economically important species of root-lesion nematodes on perennial crops
in California by genus and species. - ✔✔Pratylenchus vulnus & Pratylenchus penetrans
List the two economically important cyst nematodes in California by genus and species. -
✔✔Heterodera schachtii & Heterodera cruciferae
List five major root-knot nematodes in California by genus and species. - ✔✔Meloidogyne
Incognita (southern)
M. hapla (northern)
M. javanica (Javanese)
M. arenaria (peanut)
M. chitwoodi (columbia)
M. naasi (barley)
Egg laying habits of ectoparasitic nematodes - ✔✔Eggs are laid singly in the soil around the
roots, and females may lay up to 2,800 eggs
Egg laying habits of root-lesion nematodes. - ✔✔Female lays one to two eggs a day for many
days
Egg laying habits of stem and bulb nematodes. - ✔✔After fertilization by a male, a female
lays up to 10 eggs a day within host tissue and up to 500 eggs in a lifetime.
, Egg laying habits of foliar nematodes. - ✔✔Relatively few eggs laid. 20-30 total eggs has
been observed in one species.
Egg laying habits of citrus nematodes - ✔✔Egg masses of about 100 eggs are deposited into
a gelatinous matrix.
Egg laying habits of root-knot nematodes. - ✔✔Eggs are laid in a gelatinous matrix at
posterior end of the body, which may be within the root partially or completely. Low survival.
Sedentary ectoparasite - ✔✔Nematodes that feed on the outside of the plant in one location
for most of their life cycle.
Ex: Ring Nematode (Criconemella, Macroposthhonia)
Migratory ectoparasite - ✔✔Nematodes that feed on the outside of the plant, but will move
to different locations in their life cycle.
Ex: Dagger Nematode (Xiphinema spp.)
Migratory endoparasite - ✔✔Nematodes that feed within the plant and will move
throughout the plant tissue in their life cycle.
Ex: Lesion nematodes (Pratylenchus spp.)
Sedentary endoparasites - ✔✔Nematodes that feed within the plant in one location for most
of their life cycle.
Ex: Cyst nematodes (Heterodera spp.; Globodera spp.)
List the major environmental/ecological factors that influence the time it takes a nematode to
complete its life cycle. - ✔✔Temperature, moisture, availability of food from the host.
Identify the host(s) of some non-plant parasitic nematodes. - ✔✔Animals, humans, insects
Ectoparasite - ✔✔Nematode that feeds on the outside of the plant.
Endoparasite - ✔✔Nematode that feeds on the inside of the plant.
List three ways ectoparasitic and endoparasitic species differ. - ✔✔Ectoparasites move to
different plants.
Endoparasites move inside the plant tissue.
Ectoparastites are sampled from the soil, endoparasites are sampled from the plant.
Identify by genus and common name the major ectoparasitic nematode groups. -
✔✔Xiphinema spp. - Dagger
Belonolaimus spp. - Sting
Trichodorus spp. - Stubby-root
Longidorus spp. - Needle
Paratylenchus spp. - Pin
Criconemoides & Mesocriconema spp. - Ring
Helicotylenchus & Rotylenchus spp. - Spiral
Tylenchorhynchus spp. - Stunt
Identify by genus and common name the major endoparasitic nematode groups. -
✔✔Meloidogyne spp. - Root-knot
,Heterodera & Globodera spp. - Cyst
Pratylenchus spp. - Lesion
Radopholus spp. - Burrowing
Rotylenchulus reniformis - reniform
List the two most economically important species of root-lesion nematodes on perennial crops
in California by genus and species. - ✔✔Pratylenchus vulnus & Pratylenchus penetrans
List the two economically important cyst nematodes in California by genus and species. -
✔✔Heterodera schachtii & Heterodera cruciferae
List five major root-knot nematodes in California by genus and species. - ✔✔Meloidogyne
Incognita (southern)
M. hapla (northern)
M. javanica (Javanese)
M. arenaria (peanut)
M. chitwoodi (columbia)
M. naasi (barley)
Egg laying habits of ectoparasitic nematodes - ✔✔Eggs are laid singly in the soil around the
roots, and females may lay up to 2,800 eggs
Egg laying habits of root-lesion nematodes. - ✔✔Female lays one to two eggs a day for many
days
Egg laying habits of stem and bulb nematodes. - ✔✔After fertilization by a male, a female
lays up to 10 eggs a day within host tissue and up to 500 eggs in a lifetime.
, Egg laying habits of foliar nematodes. - ✔✔Relatively few eggs laid. 20-30 total eggs has
been observed in one species.
Egg laying habits of citrus nematodes - ✔✔Egg masses of about 100 eggs are deposited into
a gelatinous matrix.
Egg laying habits of root-knot nematodes. - ✔✔Eggs are laid in a gelatinous matrix at
posterior end of the body, which may be within the root partially or completely. Low survival.
Sedentary ectoparasite - ✔✔Nematodes that feed on the outside of the plant in one location
for most of their life cycle.
Ex: Ring Nematode (Criconemella, Macroposthhonia)
Migratory ectoparasite - ✔✔Nematodes that feed on the outside of the plant, but will move
to different locations in their life cycle.
Ex: Dagger Nematode (Xiphinema spp.)
Migratory endoparasite - ✔✔Nematodes that feed within the plant and will move
throughout the plant tissue in their life cycle.
Ex: Lesion nematodes (Pratylenchus spp.)
Sedentary endoparasites - ✔✔Nematodes that feed within the plant in one location for most
of their life cycle.
Ex: Cyst nematodes (Heterodera spp.; Globodera spp.)
