PCA Nematodes Exam Newest With Complete 100
Questions And Correct Detailed Answers| Brand New
Version!
Describe the relative size of plant feeding nematodes. - ans -Great variability.
Range from 0.25 um to 12 mm in length.
Name five to six life stages of plant-parasitic nematodes. - ans -Egg, juvenile 1, J2,
J3, J4, adult
Shape and size of root-knot nematode - ans -Females are round and lose their
veriform shape as adults, males retain veriform shape
Shape and size of cyst nematode - ans -Adult female is swollen, eggs retained
inside of cyst and cyst is left behind after female dies
Shape and size of lesion nematode - ans -Small, needle-like
Describe how nematode shape affects the choice of extraction method. - ans -
Larger nematodes that are swollen may be observed on the root system, but
smaller nematodes require actual extraction.
Define veriform. - ans -Worm-shaped
Describe the major difference between the veriform stage and other nematode
life stages. - ans -Veriform stages are mobile, swollen stages are not.
Describe the feeding apparatus of plant-parasitic nematodes and how it is used to
feed on plants. - ans -Stylet is used to feed. It pierces the plant, and draws
nutrients from the plant.
List two groups of nematodes by common name that exhibit sexual dimorphism. -
ans -Cyst and root-knot nematodes
,Describe the differences in shape between males and females in nematodes that
exhibit sexual dimorphism. - ans -Males are veriform, whereas females are
swollen.
Describe how nematodes move. - ans -Nematodes move with snake-like
movements in short distances. For long distances, they move with infected
material, water, and equipment.
List the major environmental/ecological factors that influence the time it takes a
nematode to complete its life cycle. - ans -Temperature, moisture, availability of
food from the host.
Identify the host(s) of some non-plant parasitic nematodes. - ans -Animals,
humans, insects
Ectoparasite - ans -Nematode that feeds on the outside of the plant.
Endoparasite - ans -Nematode that feeds on the inside of the plant.
List three ways ectoparasitic and endoparasitic species differ. - ans -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. -
ans -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. -
ans -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. - ans -Pratylenchus vulnus &
Pratylenchus penetrans
List the two economically important cyst nematodes in California by genus and
species. - ans -Heterodera schachtii & Heterodera cruciferae
List five major root-knot nematodes in California by genus and species. - ans -
Meloidogyne Incognita (southern)
M. hapla (northern)
M. javanica (Javanese)
M. arenaria (peanut)
M. chitwoodi (columbia)
M. naasi (barley)
Egg laying habits of ectoparasitic nematodes - ans -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. - ans -Female lays one to two eggs a
day for many days
Egg laying habits of stem and bulb nematodes. - ans -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. - ans -Relatively few eggs laid. 20-30 total
eggs has been observed in one species.
Egg laying habits of citrus nematodes - ans -Egg masses of about 100 eggs are
deposited into a gelatinous matrix.
Questions And Correct Detailed Answers| Brand New
Version!
Describe the relative size of plant feeding nematodes. - ans -Great variability.
Range from 0.25 um to 12 mm in length.
Name five to six life stages of plant-parasitic nematodes. - ans -Egg, juvenile 1, J2,
J3, J4, adult
Shape and size of root-knot nematode - ans -Females are round and lose their
veriform shape as adults, males retain veriform shape
Shape and size of cyst nematode - ans -Adult female is swollen, eggs retained
inside of cyst and cyst is left behind after female dies
Shape and size of lesion nematode - ans -Small, needle-like
Describe how nematode shape affects the choice of extraction method. - ans -
Larger nematodes that are swollen may be observed on the root system, but
smaller nematodes require actual extraction.
Define veriform. - ans -Worm-shaped
Describe the major difference between the veriform stage and other nematode
life stages. - ans -Veriform stages are mobile, swollen stages are not.
Describe the feeding apparatus of plant-parasitic nematodes and how it is used to
feed on plants. - ans -Stylet is used to feed. It pierces the plant, and draws
nutrients from the plant.
List two groups of nematodes by common name that exhibit sexual dimorphism. -
ans -Cyst and root-knot nematodes
,Describe the differences in shape between males and females in nematodes that
exhibit sexual dimorphism. - ans -Males are veriform, whereas females are
swollen.
Describe how nematodes move. - ans -Nematodes move with snake-like
movements in short distances. For long distances, they move with infected
material, water, and equipment.
List the major environmental/ecological factors that influence the time it takes a
nematode to complete its life cycle. - ans -Temperature, moisture, availability of
food from the host.
Identify the host(s) of some non-plant parasitic nematodes. - ans -Animals,
humans, insects
Ectoparasite - ans -Nematode that feeds on the outside of the plant.
Endoparasite - ans -Nematode that feeds on the inside of the plant.
List three ways ectoparasitic and endoparasitic species differ. - ans -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. -
ans -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. -
ans -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. - ans -Pratylenchus vulnus &
Pratylenchus penetrans
List the two economically important cyst nematodes in California by genus and
species. - ans -Heterodera schachtii & Heterodera cruciferae
List five major root-knot nematodes in California by genus and species. - ans -
Meloidogyne Incognita (southern)
M. hapla (northern)
M. javanica (Javanese)
M. arenaria (peanut)
M. chitwoodi (columbia)
M. naasi (barley)
Egg laying habits of ectoparasitic nematodes - ans -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. - ans -Female lays one to two eggs a
day for many days
Egg laying habits of stem and bulb nematodes. - ans -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. - ans -Relatively few eggs laid. 20-30 total
eggs has been observed in one species.
Egg laying habits of citrus nematodes - ans -Egg masses of about 100 eggs are
deposited into a gelatinous matrix.
