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Module 2: Parasitoids and Predators
Module 2: Parasitoids and Predators
144
Agriculture
Undergraduate 4
02/01/2017

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Term
2 classes of effects of paradsitoids on hosts
Definition
-Idiobiont
-Koinobiont
Term
2 families within the order Diptera that are especially well represented by parasitoids
Definition
-Tachinidae
-Sarcophagidae
Term
2 feeding approaches used by insects
Definition
-Chewing
-Sucking
Term
2 forms of development in invertebrates
Definition
-Complete (holometabolous)
-Incomplete (hemimetabolous)
Term
A good example of the use of predators for augmentative biological control
Definition
the use of predatory mites, often phytoseids, for control of mites and thrips in greenhouse pest management
Term
Adelphoparasitism
Definition
Males (from unfertilized eggs) develop as hyperparasitoids of conspecific (or sometimes other species) females; also referred to as heteronomous parasitoids; Aphelinidae

This refers to an odd form of arrhenotoky where males develop as hyperparasitoids on females of their own or another species. These parasitoids are also referred to as heteronomous parasitoids.
Term
Arrhenotokous
Definition
Females arise from fertilized eggs, males from unfertilized

this is the most common form of parthenogenesis
Term
Biological Control
Definition
The action of parasites, predators, or pathogens in maintaining another organism’s population density at a lower average than would occur in their absence
Term
Cleptoparasitoid
Definition
Parasitizes host previously parasitized by another parasitoid species; displaces previous parasitoid
Term
Complete (holometabolous) metamorphosis
Definition
-they have complete development through 4 istages
-have an egg, larval, pupal and adult stage
Term
Cotesia marginiventris
Definition
-Parasitoid of caterpillars
-Responds to plant volatiles
-This is a wasp in the family Braconidae. It has a fairly broad host range within the lepidopteran (moth) family Noctuidae. It attacks young caterpillars, and allows them to continue developing (it is a koinobiont). This parasitoid is native to the United States and is a valuable biological control agent. It is highly responsive to volatile chemical cues, and has been heavily studied for this trait.
Term
Deuterotokous
Definition
this is another form of parthenogenesis

This is rather vague and it’s unclear if it is a separate classification in reality, or merely a more extreme form of arrhenotokous. In this case, males are produced relatively rarely compared to females.
Term
Diphagous
Definition
Male on one host, female on another
Term
Generalists
Definition
feeding on a wide variety of prey
Term
Hyperparasitoid
Definition
Develops in or on life stages of another parasitoid; may be secondary or tertiary parasitoids, and may be facultative or obligate
Term
Idiobiont
Definition
Host ceases to feed, grow or metamorphose after parasitism; or non-growing host stages parasitized; makes do

In this case the parasitoid causes the host to stop feeding and growing. In most cases the parasitoid paralyzes its host and the offspring must use the resources that are available at the time of oviposition.
Term
Incomplete (hemimetabolous) metamorphosis
Definition
-incomplete development through 3 stages
-have only 3 stages, egg, nymphal and adult
Term
Koinobiont
Definition
After parasitism the host continues to feed, grow, and metamorphose to a certain point, when the host is killed

This refers to parasitoids that allow their host to continue to grow after oviposition. In this case, females allocate offspring to hosts not on the basis of what is currently available, but rather on the basis of what they anticipate becoming available during the lifespan of the offspring. At some point then, the offspring themselves will kill the host.
Term
Larval parasitoids
Definition
develop entirely within the host larvae
Term
Monophagous
Definition
Restricted to single species, genus, or family
Term
Oligophagous
Definition
Subjective term; typically means that the parasitoid has a limited host range but is not tightly restricted to just one or a few species
Term
Polyphagous
Definition
Attacks variety of host taxa (usually multiple families or orders)
Term
Predator
Definition
An animal that eats more than one other animal during its life
Term
Solitary parasitoids
Definition
develop individually within the host
Term
Specialists
Definition
focusing on one or a limited number of species
Term
Superparasitism
Definition
Host is infested by more parasitoids of the same species than the host can adequately support, in some cases resulting in total parasitoid death
Term
The five generally accepted steps in the parasitoid foraging behavior paradigm
Definition
1) location of host habitat
2) location of hosts within the habitat
3) acceptance of the host for egg laying
4) the suitability of hosts for development of the parasitoid
5) in some cases the parasitoid has to manipulate the host to make it suitable for offspring development
Term
The landmark example of the use of predators in classical or importation biological control
Definition
the use of the vedalia beetle to control cottony cushion scale, thereby saving the citrus industry at the time.
Term
Thelytokous
Definition
Females arise from unfertilized eggs

this is another form of parthenogenesis, and in this case males are essentially nonexistent, and daughters are produced without fertilization by unmated females

Most cases of this form of sex determination appear to be related to infections of sex modifying bacteria such as Wolbachia.
Term
an example of conservation biocontrol
Definition
Effect of Conservation Strips on the Abundance and Distribution of Natural Enemies and Predation of Agrotis ipsilon (Lepidoptera: Noctuidae) on Golf Course Fairways
Term
an example of how symbiotic bacteria can confer resistance to certain parasitoids
Definition
the pea aphid and its parasitoid Aphidius ervi
Term
an example of physical attacks
Definition
Copidosompsis tanytmemus attacking moth eggs This is a polyembryonic species that typically lays a single egg from which hundreds of larvae eventually develop. But one subset of those larvae becomes a group of defenders that aggressively attack and destroy any other parasitoids that try to develop in the host. These defenders will never become adults, but will spend their entire short lives defending their siblings within the host. This is a particularly interesting system because of its ramifications for genetic control of development. All of the siblings are clones of one another, yet one small group is directed to become defenders, whereas the majority go on to become normal wasps.
Term
an example of the inoculative augmentation approach to biological control
Definition
the use of Encarsia, which are parasitoids of white flies
Term
an example of the inundative augmentation approach to biological control
Definition
Trichogramma wasps are used worldwide on a variety of crops, and some of these include corn, sugarcane, cotton, vegetables, tree fruits, etc. In fact, they are the most widely used egg parasitoid in the world, and about 30 million hectares of land are treated annually with these little wasps.
Term
an example of using inhibitory secretions to reduce the suitability of hosts for subsequent parasitoids
Definition
In a few cases, such as that of the fruit fly parasitoid Leptopilina heterotoma, the developing larvae within the host produce inhibitory secretions that essentially poison their competitors.
Term
an example of using oxygen depletion to reduce the suitability of hosts for subsequent parasitoids
Definition
depleting the oxygen to such a level that competitors suffocate, as is the case of the parasitoid Horogenes chrysostictos against it’s competitor Nemeritis canescens
Term
augmentation
Definition
Augmentation is, as the word suggests refers to adding more individuals of the natural enemy to supplement those already present. Augmentation can be through inoculative releases, where a few individuals are released at a critical time or season; or through inundative releases, where millions of individuals are released.
Term
augmentation is conducted by...
Definition
Farmer/Gardener
Term
classes of parasitoids based on the host stage utilized
Definition
-egg parasitoid
-larval parasitoid
-egg-larval parasitoid
Term
conservation
Definition
Conservation deals with protecting and encouraging the existing natural enemies in an environment, through various means like providing food sources, nesting or breeding spots, and avoiding or reducing chemical interventions.
Term
conservation is conducted by...
Definition
Farmer/Gardener
Term
cost of augmentation
Definition
Subjective to crop
Term
cost of conservation
Definition
Low
Term
cost of importation
Definition
High initial, then low
Term
depiction of parasitoids related to trophic levels
Definition
[image]

We typically have a basal host that is an herbivore. This herbivore is attacked by a primary parasitoid. But primary parasitoids can themselves be attacked by parasitoids which can be referred to as secondary parasitoids. These in turn on occasion may be attacked by another trophic level of parasitoids, which are termed tertiary parasitoids.
Term
ectoparasitoids
Definition
develop on the outside of the host
Term
efficacy of augmentation
Definition
Moderate to high
Term
efficacy of conservation
Definition
Moderate to low
Term
efficacy of importation
Definition
high
Term
egg parasitoids
Definition
lay their eggs inside of host eggs, and complete the development inside the egg
Term
egg-larval parasitoids
Definition
I think this refers to parasitoids capable of spanning multiple life stages
Term
endoparasitoids
Definition
develop on the inside of the host
Term
environmental friendliness of augmentation
Definition
friendly
Term
environmental friendliness of conservation
Definition
friendly
Term
environmental friendliness of importation
Definition
friendly
Term
example of the conservation approach to biological control
Definition
reducing the use of pesticides to allow Cotesia to control beet armyworm
Term
example of the importation approach to biological control
Definition
the encyrtid wasp Apoanagyrus lopezi was introduced from the Americas to Africa to combat Cassava mealybug, which was a severe pest on cassava IT WORKED!
Term
four approaches used with Encarsia as an augmentative biological control agent
Definition
1: “Pest in first” – deliberately release whiteflies
2: “Dribble method” – Start introducing wasps at planting to have wasps in place when pests arrive
3: “Banker plants” – Establish wasps on other plants that already have infestations; allow wasps to move to new infestations
4: Inundative releases: Repeated releases of large numbers of parasitoids
Term
gregarious parasitoids
Definition
develop in groups within a host
Term
how endocrine interactions can be used by parasitoids to regulate hosts
Definition
Parasitoids are also capable of modifying endocrine interactions with the host, affecting the ability of the host to develop, utilize food resources, and in some cases the parasitoid is able to usurp the hosts hormones for its own development. The hormonal interactions between parasitoids in the hosts have not been worked out in great detail as of yet, there are clear indications that these relationships are quite complex.
Term
how parasitoids can use physiological suppression to reduce the suitability of hosts for subsequent parasitoids
Definition
-Oxygen depletion
-Inhibitory secretions
Term
how parasitoids can use viruses for host regulagtion
Definition
Viruses can contribute to specificity or breadth of host range
Term
how sustainable augmentation is
Definition
low
Term
how sustainable conservation is
Definition
high
Term
how sustainable importation is
Definition
high
Term
how the response of the host can help the parasitoid decide on the suitability of the host
Definition
-If the host exhibits a very vigorous defensive response, then the parasitoid gets very excited and recognizes that this is a healthy host and will attack it.
-If the pest response is subdued or nonexistent, and parasitoid use this test will reject the host.
Term
importation
Definition
Importation is also called “classical biological control”. Importation involves introduction of natural enemies from a different locality, or country to a place where they do not occur naturally and this is done to control a pest that might have been accidentally introduced to a new area. This can be a long and cumbersome process. It involves searching for the origin of the pest in question, and then extensive exploration to determine if any natural enemies are present. Then those natural enemies are collected and brought into the required country, where they are placed in quarantine and undergo several rigorous testing procedures to ensure their safety to the environment, before being ultimately released.
Term
importation is conducted by...
Definition
International, Federal, State agencies (later, farmers help)
Term
in augmentation, the natural enemy cones from...
Definition
already there
Term
in conservation, the natural enemy cones from...
Definition
already there
Term
in importation, the natural enemy cones from...
Definition
elsewhere
Term
inundative releases in augmentative biological control
Definition
large numbers of parasitoids are released and this is done in certain conditions, as when the cropping season is too short for the population to develop, or the host (whitely) or the plant are not suitable. This method is most common in ornamental crops.
Term
location of adult parasites
Definition
in/on host
Term
location of adult parasitoids
Definition
Free-living
Term
location of adult predators
Definition
Free-living
Term
location of immature parasites
Definition
In/on host
Term
location of immature parasitoids
Definition
In/on host
Term
location of immature predators
Definition
Free-living
Term
monoembryonic
Definition
a single egg yields a single embryo

this is characteristic of most parasitoids
Term
multiple parasitism regarding parasitoids
Definition
parasitoids of different species successfully completing development within the same host
Term
number of host a parasite has
Definition
1 to a few
Term
number of host a parasitoid has
Definition
1
Term
number of host a predator has
Definition
many
Term
parthenogenesis
Definition
virgin females are capable of reproducing
Term
picture of Cotesia marginiventris
Definition
[image]
Term
pictures of Green Lacewing (Family Chrysopidae)
Definition
[image]
Term
polyembryonic
Definition
multiple embryos are produced by single egg
Term
size of parasite relative to its host
Definition
small
Term
size of parasitoid relative to its host
Definition
large
Term
size of predator relative to its host
Definition
large
Term
some details about Green Lacewing (Family Chrysopidae)
Definition
Our bug of the day is a very important natural enemy in many crop systems. They typically lay individual eggs, but they may also be clumped in some species. Eggs of nearly all species are laid on stalks, presumably to reduce predation risks. The larvae are very active predators of aphids and other soft-bodied insects. The last instar larva spins a small circular cocoon in which it pupates.

Here we have an image of a larva feeding on an aphid on the left, and the adult on the right. These are green lacewings. Adults of many of the common species are not predators, but there are many species that are predatory as larvae and as adults. A few species are available commercially and are used in biological control programs.
Term
some details about the family Mantispidae
Definition
-Mantispidae are fairly specialized on spider egg cases.
-The female lays masses of eggs as shown here on the stem, in the newly hatched larvae make their way to spider a cases.
-They enter the egg case before molting to the next life stage, which has reduced legs.
-They spend their entire immature life in the host egg case.
-The close relationship of Mantispidae with spiders, and specialized larval stages for survival in the host egg case have suggested to some that they should be classified as parasitoids.
-Others have argued that they are essentially specialized predators because each immature mantispid must consume multiple prey to complete its development.
Term
some details about the order Coleoptera
Definition
-contains beetles in the families Meloidae, Carabidae, and Staphylinidae
-Among the beetles there are several families that have representatives with parasitoid lifestyles. One that has been used in biological control programs is a subfamily in the family Carabidae, the subfamily Lebiinae, which includes beetles that are parasitoids of leaf beetles, including the Colorado potato beetle.
-An interesting group of parasitoids is found in the family Meloidae, which are commonly known as the blister beetles.
-The adults of all species are known to be plant feeders, whereas larvae are either parasitic or predaceous. The parasitoids attack ground-nesting bees.
-The eggs are typically laid on the ground, and the larvae are active triungulins that go hunting for hosts, or bait the hosts, as the cluster of triungulins shown here is mimicking a bee and when a male becomes to mate with it, instead finds himself crawling with triungulins that he carries back to the nest.
Term
some details about the order Diptera
Definition
-Flies
-Various families (Tachinidae, Sarcophagidae)
-in Georgia in the southeastern United States in general, in the past few years parasitoids in the family Phoridae have become quite notorious; within this family, several species of fly have been released in the region for biological control of the fire ant; these are the so-called decapitating flies
Term
some details about the order Hymenoptera
Definition
-Bees, ants wasps
-Numerous families
-largest group of parasitoids
-most important group
-contains the largest number of parasitoids
-most important in biological control of the parasitoids, at least numerically
-This is a very large order both taxonomically and biologically, with very diverse organisms that comprise bees, ants, and wasps
Term
some details about the order Neuroptera
Definition
-sometimes included among the parasitoids
-has a single family exhibiting such behavior (Mantispidae)
Term
some details about the order Strepsiptera
Definition
-Twisted-wing parasite
-a small one that is entirely made up of parasitoid, although some are closer to being true parasites
-relatively small order of just a few hundred species, but they are very odd parasitoids
-They attack bees, wasps, various leaf hoppers and plant hoppers, and a few other species
-Females are wingless and live their lives inside the host, typically protruding from the host body as they mature and become fully reproductive
-Adults, on the other hand, emerge from the host with wings and are quite bizarre looking
-The females produce a large number of offspring, in the form of functional larvae rather than eggs. These larvae are referred to as triungulins, and they actively leave the mother’s body and search out new hosts
Term
some details about the parasitoid group Aphelinidae
Definition
-Tiny parasitoids of aphids, whiteflies, scales
-Valuable biological control agents
-Wild biologies
-The Aphelinidae is a family of about 2,000 species of tiny parasitoids that typically attack aphids, whiteflies, and scales. In this role they have been extremely valuable in biological control, as these host groups are also important pests in many systems. Some are also important enemies in eggs of Lepidoptera and Orthoptera, and in eggs, larvae, and pupae of Diptera. They have some very intriguing biologies. There are both ecto- and endoparasitoids in the family. It is in this family where we find the heteronomous parasitoids – those species in which males are hyperparasitoids of females of their own or another aphelinid species. In some species males and females develop on the same species, with males as ectoparasitoids and females are endoparasitoids
Term
some details about the parasitoid group Braconidae
Definition
-Very large and important group with diversity of habits and host ranges
-Another very large family (estimated 60-100,00 species) of parasitoids ( a few phytophagous species), and one that is very important in biological control. Braconids attack a wide range of hosts in the Holometabola (mostly larval stages, but some pupae and adults, as well), but also in the Hemiptera, and hyperparasitism is very rare in this family. Some species are enemies of important natural enemies, such as lady beetles and lacewings. Members of this family spin cocoons at the time of pupation.
-Resemble Ichneumonids (same superfamily)
-Key character is only one recurrent vein in wing
-Distinguishing between Ichneumonids and Braconids is about the veins in the forewings. Whereas Ichneumonidae have two recurrent veins, Braconidae only have one.
Term
some details about the parasitoid group Carabidae
Definition
-Huge family of beetles, parasitoids (Lebiinae) of leaf beetles
-First abdominal sternum divided by hind coxae, and large hind trochanters
-The family Carabidae is a huge group with very diverse biologies, ranging from predation to parasitism to herbivory. One family, the Lebiinae, contains parasitoids of beetles in the family Chrysomelidae (the leaf beetles). Adults of these parasitoid species are predators. Some are useful parasitoids and predators of Chrysomelid pests, such as the Colorado potato beetle and the Altica flea beetle. Carabids can be distinguished by the progressive narrowing from abdomen to thorax to head, and by the large “jelly-bean” like trochanters on the legs, and the subdivision of the first abdominal segment on the underside by the hind coxae.
Term
some details about the parasitoid group Chalcididae
Definition
-Diverse hosts, some hyperparasitoids, superparasitism common
-Chalcidids are interesting parasitoids that attack a wide variety of insect and spider hosts, although most are parasitoids of Lepidoptera. A number of species are hyperparasitoids, and superparasitism in the group is rather common, as females exhibit limited powers of host discrimination. They tend to attack only host larvae or pupae. There are about 2,000 estimated species.
Term
some details about the parasitoid group Charipidae
Definition
-Hyperparasitoids of aphid parasitoids
-Smooth, shiny body,
-Abdomen laterally compressed,
-Very small wasps
-This family is essentially specialized as hyperparasitoids of parasitoids attacking Homopteran pests (aphids and Psylloids), and can be very disruptive to biological control programs against these pests. Their primary targets are Braconidae, Aphelinidae, and Encyrtidae, which we will discuss later.
Term
some details about the parasitoid group Chrysididae
Definition
-Beautiful, metallic colors, often curled into ball when dead
-Body strongly sculptured, sclerotized
-Attack sphecoid and vespoid wasps
-Many are cleptoparasites
-These gorgeous wasps are heavily sclerotized, meaning what? They often curl into a ball when dead or disturbed. This is a defensive response. These wasps are paarsitoids of sphecoid and vespoid wasps, such as paper wasps and mud daubers. These hosts have strong defensive tools, and the Chrysidids, commonly called cuckoo wasps, are heavily armored and when attacked roll into a ball, making themselves impervious to attack. Many species are cleptoparasites, stealing the food that is placed in the host cells by the provisioning mother, and consuming the host larva to boot. Their theft of food for the host larva is why they are called cuckoo wasps, similar to the action of the cuckoo bird.
Term
some details about the parasitoid group Encyrtidae
Definition
-Important parasitoids of scales and other Homopterans
-Some hyperparasitoids, polyembryony
-These small parasitoids have been used in a number of biological control programs against scales and other Homopteran pests, as well other pests, such as gypsy moth. Some species also attack other natural enemies (such as lady beetles and lacewings). Some species are hyperparasitoids. Polyembryony is also found in this group (the Subfamily Copidosomatini), including the looper parasitoid we discussed in the last lecture, where a single egg may yield more than a thousand parasitoids, and a small subset of the larvae are defender morphs that defend their siblings from competitors, but never become adult wasps. All known species are endoparatisoids of various life stages (eggs, larvae, nymphs, pupae). The adults of these wasps are characterized by an abdominal “smile” created by a pulling forward of the abdominal sclerites on the sides.
-Look for the abdominal “smile”
Term
some details about the parasitoid group Eulophidae
Definition
-Very diverse group; Some hyperparasitoids; Some phytophagous
-Look for 4 tarsal segments
-Very diverse family of about 5,000 species that has also been used with success in biological control. Most are primary parasitoids of (often concealed) larvae Lepidoptera, Coleoptera, Diptera, and Hymenoptera (although other orders also are attacked by some species), but some species are phytophagous, and others attack egg stages of their hosts. They have been reared from many hosts worldwide, and have been particularly useful in biological control of leafmining flies.
Term
some details about the parasitoid group Evaniidae
Definition
-Abdomen attached high on thorax
-Roach egg parasitoids/ predators
-Strongly petiolate, triangular abdomen
-Evaniids are fascinating wasps that attack egg cases of cockroaches. They attack the egg cases before they harden, typically laying just one or a few eggs in the egg case. The first larval instar is a true parasitoid, but after it molts, it becomes a predator, consuming most or all of the remaining eggs in the egg case. The adults have long legs for running, and are called ensign wasps because of their rapid up-and-down movement of the abdomen that resembles a signal flag. These wasps are very distinctive, with their abdomens attached high up on the thorax, and a small triangular abdomen attached by a very petiolate propodeum.
Term
some details about the parasitoid group Ichneumonidae
Definition
-Very large and important group with diversity of habits and host ranges: all parasitoids
-This is a huge family of parasitoids, with an estimated 100-200,000 species. The hosts of this family tend to be concentrated on larval and pupal stages of the Holometabola, or those insects with complete development. Some species attack spider egg cases, and some are egg-larval parasitoids. Some species are very important natural enemies of pests, others are hyperparasitoids, and others attack other beneficial species. Some species have extreme morphologies, such as the Megarhyssa shown here, which attacks woodboring beetles. The primitive groups are ectoparasitoids, while endoparasitism dominates in advanced taxa.
-Females often have exserted ovipositors
-Distinguishing character is second recurrent vein in wing
-Ichneumonids have a rather distinctive form, but are similar to another large family, the Braconidae, to which they are related. Differentiating these two species is done be examining the wing veins. Ichneumonidae have two recurrent veins, forming a cell
Term
some details about the parasitoid group Meloidae
Definition
-Blister beetles; often find adults on flowers
-Prothorax narrower than head and abdomen
-Another group of parasitoids among the beetles is the Family Meloidae. These are interesting beetles that can induce blister formation with their defensive secretions. Unlike the Carabidae, the thorax of these beetles is narrower than the head.
-Blister beetle adults are plant feeders (some pests)
-Immature stages (triungulin) attack hosts, such as bees and wasps, or grasshoppers
-I showed you these slides in the last lecture. Blister beetles are herbivorous as adults, and some are serious crop pests. The initial immature stage is referred to as the triungulin, and they actively seek or bait hosts, which are ground-nesting bees.
Term
some details about the parasitoid group Mymaridae
Definition
-Very tiny egg parasitoids
-Especially important against true bugs
-These are extremely tiny egg parasitoids, and the family is estimated to consist of about 1,500 to 2,000 species. All are egg parasitoids, mostly of eggs that are concealed or inserted into plant tissues (Hemiptera), but also some Coleoptera are known hosts. They have been used in some biological control programs, but most host relationships are poorly known.
Term
some details about the parasitoid group Sarcophagidae
Definition
-Large and diverse family, many parasitoids
-Lack subscutellum; often have red on abdomen; most larviporous
-Often have checkerboard pattern on abdomen
-A subset of these flies are parasitoids, mostly on Orthoptera and Lepidoptera. This family has very diverse biologies, including among the parasitoid species. Some species use phonotaxis (sound orienting) to locate their cicada hosts.
Term
some details about the parasitoid group Scelionidae
Definition
-Very tiny egg
parasitoids
-Body heavily sclerotized and usually smooth and shiny
-Valuable group in biological control. Estimated at about 7,000 species in the family. No known hyperparasitoids in the family, and they concentrate on eggs of a variety of insects and spiders. For example, several species are very effective parasitoids of green lacewing eggs, and can seriously hamper use of green lacewings in biological control. Others have been used quite effectively in biological control programs against bug pests and Lepidopteran pests.
Term
some details about the parasitoid group Tachinidae
Definition
-Largest fly family of parasitoids
-Have swollen subscutellum
-Diverse biologies, hosts
-More than 8,000 known species in this family, all of which are parasitoids. They are virtually all endoparasitoids, but some behave more as true parasites. Members of this family have been used successfully in biological control programs. Some species lay eggs in the environment for hosts to consume, some lay deposit triungulin larvae that actively search for hosts, some lay eggs on the outside of hosts that hatch shortly after deposition and the larvae enter the hosts, and some deposit larvae directly into hosts.
Term
some details about the parasitoid group Trichogrammatidae
Definition
-Very tiny egg parasitoids
-Important in biological control
-Estimated 1-2,000 species of tiny parasitoids. All are egg parasitoids of Holometabola and Hemiptera, Orthoptera, and Thysanoptera. The taxonomy of the group is a mess, but three tarsal segments are diagnostic for the family. These parasitoids are used worldwide in release programs against crop pests, mostly Lepidopterans.
Term
some examples of parasitoids accepting the host
Definition
-Telenomus heliothidis will sting non-host eggs if they are treated with material from the accessory glands of the normal host – Heliothis virescens -Edovum puttleri will sting glass beads if they are treated with hexane wash of eggs of the normal host - Leptinotarsa decemlineata
Term
some examples of parasitoids locating the host habitat
Definition
-Leptopilina heterotoma using volatile odors from decaying fruit to find the Drosophila larvae they attack -the use of sound by mole cricket parasitoids to locate their hosts’ habitats and the hosts within them
Term
some examples of parasitoids locating the host within the habitat
Definition
-a parasitoid fly that attacks gypsy moth larvae. In this case the parasitoid forages in the habitat where the hosts are located, and places it takes on the portions of leaves where it finds fresh feeding damage. The gypsy moth larvae then consume the fly egg while they are feeding, the egg hatches inside of the caterpillar, and parasitism is underway. So, in this case the parasitoid locates the host habitat, finds locations where the host is feeding, then leaves little time bombs for the host.
-responding specifically to cues that direct them to their hosts within the habitat, such as a wasp attacking caterpillars that are significant pests in cotton, corn, peanuts, soybeans, tomatoes, tobacco, and other crops
Term
some factors that affect host suitability
Definition
-Host age or life stage
-Host diet – Nicotine, e.g.
-Parasitization status of host
-Health of host
Term
some forms of parthenogenesis
Definition
-Arrhenotokous
-Deuterotokous
-Thelytokous
-Adelphoparasitism
Term
some insects with Complete (holometabolous) metamorphosis
Definition
Holometabolous orders of insects include the moths and butterflies, bees, ants and wasps, beetles, lace wings and flies
Term
some insects with Incomplete (hemimetabolous) metamorphosis
Definition
Examples of insects with incomplete metamorphosis include all of the true bugs, dragonflies and damselflies, grasshoppers, and mantids
Term
some means by which parasitoids regulate their hosts
Definition
-toxins injected into the host by the ovipositing female
-viruses which the female inserts into the host along with her eggs
-teratocytes, which are tiny cellular components of eggs that are released into the host when the egg hatches and which modify the nutrient quality of the host or suppress the host immune system
-other mechanisms
Term
some orders parasitoids can be found in and some details about each
Definition
-Hymenoptera: Numerous families; largest group of parasitoids; most important group
-Diptera: Various families (Tachinidae, Sarcophagidae)
-Strepsiptera: Twisted-wing parasite*
-Coleoptera: Meloidae, Carabidae, Staphylinidae
-Neuroptera: Mantispidae*
Term
some problems with vertebrate predators
Definition
1. They tend to have a broad host ranges
2. they are very capable learners.

This means that vertebrate predators can readily switch to new prey in an often unpredictable fashion!
Term
some ways parasitoids can reduce the suitability of hosts for subsequent parasitoids
Definition
-Internal Host Discrimination
1. Marked Hosts
-Eliminate competitors
2. Physical attacks
Term
specificity of the targer in augmentation
Definition
specific to a group
Term
specificity of the targer in conservation
Definition
general
Term
specificity of the targer in importation
Definition
highly specific
Term
the "banker plants" system in augmentative biological control
Definition
in this system, Banker Plants are used, which are plants from an earlier grown crop that have established infestations of whiteflies and parasitoids. These banker plants are introduced into the fresh greenhouse crop at fixed rate, so that the parasitoids can move to find new hosts.
Term
the "dribble method" in augmentative biological control
Definition
in this method, parasitoids are introduced into the greenhouse at planting of the crop, in anticipation of the pest development. After this, low rate releases are continued, until other parasitized nymphs are found on the crop.
Term
the concern with predators
Definition
The concern is that they may attack unintended non- target species.
Term
the effect of a parasite on its host
Definition
Host lives
Term
the effect of a parasitoid on its host
Definition
Kills host
Term
the effect of a predator on its host
Definition
Kills prey
Term
the three approaches to biological control
Definition
-Importation
-Augmentation
-Conservation
Term
the “Pest-in-first” method in augmentative biological control
Definition
in this method, the pest or whiteflies are deliberately introduced into the greenhouse at a fixed rate. Later the parasitoid Encarsia is introduced at a standard rate, two or three times at regular intervals so that suitable host stages are available for them. This method is not widely popular because of obvious reasons – releasing pests directly onto the crop!
Term
where adult parasites get their nutrition
Definition
Host material
Term
where adult parasitoids get their nutrition
Definition
Host fluids, Carbs
Term
where adult predators get their nutrition
Definition
Various
Term
where immature parasites get their nutrition
Definition
host
Term
where immature parasitoids get their nutrition
Definition
host
Term
where immature predators get their nutrition
Definition
prey
Term
why predators are considered higher risks for importation than parasitoids
Definition
because predators tend to be considerably more generalized in their diets than parasitoids
Term
[image]
Definition
Cotesia marginiventris
Term
[image]
Definition
Green Lacewing (Family Chrysopidae)
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