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HABITAT, HOST-FINDING
AND HOST ACCEPTANCE
Among
Arthropods
(Contacts)
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Characteristics of the Habitat Influence
Natural Enemies |
|
Host
Food Affects Suitability for Parasitization |
|
Habitat
Diversity vs. Similarity Affects
Population Stability |
|
[Please refer also to Selected Reviews |
Although a
few species of parasitoids attack only a single host species, most of them
attack several different hosts in nature. No parasitoids are completely
indiscriminate, however. Under natural conditions, a parasitoid will attack only
a fraction of the species on which development is actually possible. The processes
in host selection involve four main steps: (1) host-habitat finding, (2)
host-finding, (3) host acceptance and (4) host suitability. A fifth
criterion, host regulatory capacity, is sometimes proposed, but it refers to
the ability of the parasitoid to change biochemical reactions in the host. It
is confused with the ability of the parasitoid to regulate its host's
population density, and therefore is a poor choice of terms. Habitat
Effects on Natural
Enemies Picard & Rabaud (1914) observed that
many parasitic Hymenoptera attack larvae of species in different families and
even different orders, provided that the hosts feed on the same species of
food plant. Cushman (1926) cited two cases where the same parasitoid attacked
two different insects belonging to two different orders because of its habit
of parasitizing leaf miners. It was recognized that the systematic
relationship was not important, but rather the fact that both hosts were
mining in a leaf. Laing (1937) observed that Alysia manducator (Panzer) was attracted to the odor of
decomposing meat even in the absence of hosts, which in this case were
carrion flies. She also observed that Nasonia
vitripennis was attracted to
carrion, but that Trichogramma
evanescens West was rather
attracted by the sight of the host and not by odor of the eggs of Sitotroga cereallella (Olivier). This and other work led her to
propose three steps in the attack activity of a parasitoid: (1) attraction to
the host habitat, (2) attraction to host individuals in the habitat and (3)
acceptance or rejection of the host. Flanders (1937) working in the same time
period observed a fourth step in the parasitization process. His proposed steps
were (1) host habitat finding, (2) host-finding, (3) host acceptance and (4)
host suitability. There have been many restatements of these
procedures in host selection that did not add anything significant to those
rather clearly and thoroughly outlined above, although new species of natural
enemies were considered (Hodek 1966 with coccinellids; Monteith 1955 with
tachinids; Salt 1935, 1958 with parasitic Hymenoptera; and Thorpe &
Caudle 1938, with ichneumonids, to mention just a few). As a forerunner of
the idea of a sequence of events leading to host selection, Davis (1896)
observed, without indicating the cause, that some plants such as Nicotiana, Pelargonium, Datura,
Eucalyptus, etc., were
repellent to Encarsia formosa Gahan, a whitefly
parasitoid. The behavior of the natural enemy to be
attracted to a specific habitat rather than directly to the host in the
habitat is very important in biological control, and ignoring this important
step in natural enemy attack behavior still continues to lead novice
biological control workers astray. Flanders (1940) even indicated that the
presence of uninfested plants having greater attractiveness than infested
plants may prevent the establishment of the colonized parasitoid. Salt (1935) considered that, "It is obvious
in the first place that in order to interact, the parasite and the host must
meet. Now, it is certain that some parasites, and probably more, are first
attracted not to a particular host but to a certain type of
environment." Smith (1949) believed that, "Recognition must be
given to the possibility that the host plant may confer on the host insect a
kind of immunity to parasitization." With these and many more statements
over the years emphasizing the importance of habitat or environment, there is
no excuse for errors to continue to be made. The term "ecologically incomplete parasitism" has
been coined for situations when the number of host habitats in which a highly
suitable host is susceptible to attack is less than the total number of
habitats occupied in common by this host and its parasitoid (Flanders 1953).
For example, prior to 1940 the lack of attractiveness to the parasitoid by
citrus trees could account for inadequate control of the black scale by its
parasitoid in southern California (Flanders 1940). Van Steenburg as early as 1934 observed that
when a species is liberated in a habitat which is not suitable for it, it
soon disappears, even in the presence of suitable hosts. This was
demonstrated with two species of Trichogramma
in peach orchards. The native species of parasitoid persisted and the
imported ones which were released disappeared. Characteristics
of the Habitat
that Attract or
Repel Natural
Enemies The
external leaf structure effects natural enemy activity. Downing &
Moilliet (1967) found the highest populations of predaceous mites in the
varieties Spartan and McIntosh apples having hairy leaves and pronounced
veins, which create more sheltered areas for phytoseiids and more protection
from macropredators such as Hemiptera. The Delicious variety had the lowest
numbers of predators presumably due to the smoothness of the leaves. Putman & Herne (1966) found the same
relationship with peach varieties: mirid predators of Panonychus ulmi
were more abundant on hairy-leafed varieties. A higher Heliothis
egg parasitism by Trichogramma
was recorded on the smooth upper surface of corn leaves than in any other
part of the plant (Phillips & Barber 1933); and Milliron (1940) obtained
the highest parasitism of the greenhouse whitefly by Encarsia formosa
on smooth leaves, and the lowest parasitism on pubescent leaves. Thompson (1951) explained the failure to
establish twelve species of coccinellids in Bermuda for diaspine scale
control on cedar, on the fact that the cedar leaves were so short, rigid and
hard to move that the beetles could not grip the scale bodies. Leaf exudations can influence parasitoid
activity. Rabb & Bradley (1968) found that Trichogramma and other parasitoids failed to attack Manduca eggs on fresh tobacco leaves
because parasitoids became stuck in the gummy exudate of the trichomes.
Milliron (1940) observed that droplets of honeydew disturbed Encarsia formosa on the whitefly host. Odor of the host food is thought to have a
very significant influence on natural enemy activity. The ichneumonid Nemeritis canescens Gravenstein, which is parasitic on Ephestia kuhniella (Zeller), is first attracted to the odor of the
larval food, oatmeal (Thorpe & Jones 1937). Alysia manducator
and Nasonia vitripennis are attracted to
decomposing meat on which the maggots of their host feeds (Laing 1937).
Edwards (1954) refuted Laing's finding by recognizing that the attraction of Nasonia was actually to the
combination of decomposing meat plus the presence of host larvae, but not to
either alone. Thorpe & Caudle (1938) observed that
immature females of Pimpla ruficollis Gravenstein were
repelled by the odor of oil secreted by Pinus
silvestris, whereas sexually
mature females were strongly attracted. This was especially significant because
the period of repellency coincides with the period in which the host
caterpillar (pine shoot moth) is not yet available for the parasitoid. An
identical situation with another parasitoid, Eulimaeria eufifemur
Thorn, was found. Parker (1918) had found something similar with Chloropisca glabra Meigen, but did not
recognize it as repulsion. In this case attraction occurred only when ovarian
development was complete. The tachinid parasitoid of Diprion hercyniae (Htg.) is strongly attracted by the odor of old
plant growth. There were thirteen times as many attacks when the host
occurred on new growth (Monteith 1966). In fact both hosts and parasitoids
apparently preferred old growth. Host
Food Affects Suitability For
Parasitization Numerous authors have observed that the food
of the host may affects its parasitoids. Simmonds (1944) reported three to
four times more parasitism by Comperiella
bifasciata Howard on Aonidiella aurantii Maskell on oranges than on lemons. He attributed
this to the fact that since host-feeding is involved the scale body fluids
acquire a distinctive character from the host plant that could affect the
parasitoids' vitality and fecundity. Smith (1957) observed this also but did
not relate it to Simmonds' work. Hodek (1966) gave an example of food
toxicity to natural enemies. Rodolia
(Novius) cardinalis Malshant did not
prey on Icerya purchasi Maskell when it was
feeding on two plants in the family Viciacae, Sparticum tunceum
and Genista aetnesis. The yellow pigment
genistein and alkaloids that these plants contain are harmful to Rodolia. Other examples are
Morgan (1910), Gilmore (1938), Flanders (1942) and Lawson (1959). Other
Influences of Habitat Collyer (1958) registered higher populations
of Typhlodromus tilliae Ondems on larger plants
than on smaller plants. She concluded that the rate of development of the
predator depended on the size of the host plant. Graham & Baumhoffer (1927) and Arthur
(1962) reported that bud size of different pine tree species influenced the
degree of parasitism on lepidopterous pests of these plants. The smaller the
buds, the higher the percent parasitism. Smaller buds do not afford adequate
protection to host larvae. Franklin & Holdaway (1960) found that the
parasitoid of the European corn borer, Lydella
grisescens Robineau-Desvoidy
was significantly more attracted to a certain hybrid of corn than to any
other variety. Fleschner & Scriven (1957) observed higher rates of
oviposition of Chrysopa californica (Coquillett) on
lemons growing on loose sandy soil than on trees growing on compact silt
soil. Soil type influenced natural enemy abundance on the plant. Monteith
(1964) obtained two to four times as many attacks by Drino bohemica
Mesnill and Bessa harveyi Towns on sawflies
exposed on unhealthy plants as on larvae exposed on healthy plants.
Therefore, host plant health was found to determine degree of parasitism, and
was very important to host regulation in cases of severe attacks. Still other influences of the habitat on
natural enemy activity are recorded by Flanders (1935) who observed that the
excreta of the host insect attracts natural enemies. Gullman & Hodson
(1961) found attraction to certain plant sexual structures; Ullyett (1949) to
certain host pupation depths; (Chandler (1966, 1967) to visual stimuli of the
plant, and McLeod (1951) to the height of host location. Davis (1896) and
Speyer (1929) observed repellent effects of the plant and Stary (1964) found
that when a host insect is dioecious (eg., aphids), the host is attacked by
different parasitoid complexes depending on the type of habitat in which it
occurs. Other references on this subject are Nishida
(1956), Richards (1940), Salt (1958), Tamaki & Weeks (1968), Zwolfer
& Kraus (1957), Seamans & McMillan (1935), Sol (1966), Skuhravy &
Novak (1966), DeBach, Fleschner & Dietrick (1949), Clausen (1962), Beirne
(1962), Hodek (1966), Iperti (1966), Klausmitzer (1966), and Dusek &
Laska (1966). Habitat
Diversity vs Similarity Affects
Population Stability DeLoach (1970) discussed ways to alter the
habitat that produces better control. He believed that habitat diversity is
an effective situation to increase the effectiveness of natural enemies,
particularly parasitoids and predators. Examples of areas where habitat
diversity favors greater pest population stability are in the Canete Valley
of Peru, the Waco, Texas area, the San Joaquin Valley of California, and the Mississippi delta area
of southeastern Missouri. Host
Finding Once the host habitat is located, the hosts
are subsequently found by a combination of random and directed searching such
as occurs in Angita sp., a
parasitoid of Plutella maculipennis Curtis (Ullyett
1943, 1947, Doutt 1959). Considerable research shows that various
combinations of random and directed movements (taxes) are involved.
Chemotactic, phototactic, hydrotactic and geotactic responses, among others,
all seem to play a part in the host-finding process. These responses are
variously modified by olfactory, visual and other physical stimuli that
characterize a parasitoid's prey. The sense of smell seems to be widely used
by parasitoids in locating hosts. Ullyett (1953) found Pimpla bicolor
Bouche swarmed around the pupae of the lepidopteran Euproctis terminalis
Walker on pines in South Africa. In fact, olfaction is widely used by
parasitoids in locating hosts. Bouchard & Cloutier (1985). Female Aphidius nigripes Ashmead were attracted to odors
of conspecific females (Bouchard & Cloutier 1985, Dicke et al. 1985, van
Alphen & Vet 1986) and this behavior may be acquired (Vet 1983, 1985).
Host trail odors may facilitate searching (Price 1970). Other olfactory
stimuli exist (Vet & Bakker 1985, Vet & van Alphen 1985), and some
physical host characteristics affect host selection (Weseloh 1969, 1971a,b,
1972; Weseloh & Bartlett 1971, Wilson et al. 1974). Parasitoids generally seem to be more
attracted to higher densities of the host and to certain patterns of host
distribution (Legner 1967, 1969a). The addition of kairomones to a habitat has resulted in some
parasitoids being able to locate their hosts more efficiently (Gross et al.
1975, Jones et al. 1971, Altieri et al. 1982, Gardner & van Lenteren
1986). For example, Trichogramma
respond to chemical extracts of host moth body scales, while certain
braconids respond to extracts of host larval frass. Synthesis of these
kairomones is currently being attempted in order to permit their use for
biological control on a broader scale (Lewis et al. 1971, 1972; Vinson 1968,
1975, 1976; Weseloh 1974). In some instances kairomones may function to
confuse parasitoids into lesser searching efficiency (DeBach 1944, Chiri
& Legner 1983, 1986). Eran Pichersky (2004) noted that what we perceive as
fragrances are actually sophisticated tools that plants utilize to entice or
discourage other organisms. Although volatile plant compounds probably evolved to
repel hebivores, they are now known to perform a remarkable range of
functions. Most of the animals that
interact with plants are insects that detect volatile compounds through the
antennae, or the maxillary palps.
Specialized cells on the antennae contain a single type of protein
receptor that recognizes and binds specific volatile compounds. The array of receptor-decorated cells
sends signals to the brain by way of the nervous system. Although each cell contains only one
receptor type, a single compound can be recognized by more than one
receptor. Thus the pattern of
neuronal firing that results by a specific compound or mixture will be
unique. This system is extremely
sensitive and some receptors can detect an airborne volatile at
concentrations of a few parts per billion.
For biological pest control these findings are highly
significant. Plants not only emit
volatile compounds acutely, at the site where herbivores (mites,
caterpillars, aphids, etc.) are consuming them, but also generally from
non-damaged parts of the plant. These
signals attract a variety of predatory insects that prey on the
plant-feeders. In one example
parasitic wasps can detect the volatile signature of a damaged plant and will
lay their eggs inside the offending caterpillar. The ensuing parasitoid larvae eventually destroy the
caterpillar. The growth of infected
caterpillars is markedly retarded, to the benefit of the plant. Also, volatile compounds released by
plants in response to herbivore egg laying can attract egg parasitoids and
thereby prevent them from hatching (Pichersky 2004). Synthesis of many plant volatiles is
possible, and their application with mass releases of parasitoids and
predators offers promise for increasing the extent of pest control. However, extensive field experiments
would be required to establish effectiveness for any given agroecosystem, as
theoretical predictions may not be
realized. For examples some instances
such volatiles may function to confuse parasitoids into lesser searching
efficiency (DeBach 1944, Chiri & Legner 1983, 1986). Host
Acceptance Once physical contact has been made, only
the reception of a proper combination of stimuli will trigger further
behavioral responses, resulting in acceptance of the prey; i.e., resulting
int he acts of oviposition and/or host-feeding. The stimuli for attack are
known to involve, among other factors, host odor, host size, host location,
host shape and even host motion, and the history of parasitoid larval
development (Brydon & Bishop 1945, Legner & Thompson 1977, O. J. Smith
1950, Olton 1969). Salt (1935) termed host acceptance a "Psychological Selection." Huffaker (Doutt 1959)
suggested that it be called "Ethological
Selection." Flanders maintained that the act of mating
or the presence of sperm in the spermatheca has an effect on the psychology
of the female. This was suggested by the fact that unmated females tend to
attack more host species than mated ones. In certain Aphelinidae mating has a
remarkable psychological effect because significant changes occur in the type
of host selected and the manner of oviposition. Examples are found in the
genera Aneristus, Casca, Coccophagus, Euxanthellus
and Phycus, where females
develop only as primary endoparasitoids of coccids and alyrodids. When
unmated the females of some species in these genera oviposit only
hyperparasitically in a host already parasitized by the same or similar
species. Therefore, the male develops only as a primary parasitoid of the
immature instars of its own or similar species, and the host of the male is
never the host of the female, nor the host of the female the host of the male
(Flanders 1937, 1943). In certain species of Prospaltella the male develops only as a primary
parasitoid of moth eggs. Many parasitoids are able to discriminate
between parasitized and healthy hosts and thus avoid superparasitization.
Flanders (1951) indicated that a spoor effect may be
present (a special "marker" in some species). Simmonds (1943)
indicated the existence of chemoreceptors on the ovipositor of I. canescens and Wylie (1965 thru' 1972) found the same in Nasonia vitripennis. It was suggested by Dethier (1947) that in I. canescens, "Either the sensilla which are located on
the shaft of each valvula subserve a chemoreceptor function, or the
stimulating solutions diffuse through the general cuticle of the organ, or the
solutions are advanced by capillarity up the egg tube formed by the oppressed
surfaces of the valvulae to the region of the genital openings where they may
act upon sensitive areas." Narayanan & Chaudhuri (1954) believed
that Stenobracon deesae (Cameron) could
distinguish between parasitized and healthy hosts. They wrote, "It is
probable that when a female Stenobracon
inserts its ovipositor into a host to paralyze it before oviposition, she
receives a stimulus from a healthy host which is different from that derived
from a parasitized host." Host
Suitability The fact that a parasitoid has found a
potential host within its respective habitat and has oviposited in or upon
the same is no assurance that all criteria for maintaining a host-parasitoid
relationship have been met. The host individual selected may prove unsuitable
for parasitoid development. In other words, oviposition is no assurance of
host suitability if the host individual proves to be resistant or otherwise
unsuitable for parasitoid development. A host may be unsuitable for (1) physical
reasons (too small, too thick), (2) for nutritional reasons and (3)
biological reasons: the host may be killed by the ovipositing female
following host-feeding or mutilation. The host may move and dislodge externally
attached parasitoid eggs or larvae. The host may molt and thus shed
parasitoid eggs attached externally to the cast exuvium. Also, internally
laid eggs and endoparasitoid larvae may be encapsulated by phagocytes. Phagocytes are blood cells that gravitate to
and either ingest or surround foreign bodies that are introduced into the
haemocoel of a host insect. The process is called phagocytosis. Bess (1939) first recognized that
oviposition by a parasitoid is not necessarily an index to host suitability,
the attractiveness of the host being often independent of its suitability for
parasitoid development. Muldrew (1953) suggested that a once
susceptible host population [that probably contained a few resistant
individuals] may become totally resistant to parasitoid attack. In this case
the larch sawfly host, Pristiphora
erichsonii (Hartig),
inhibited the embryonic development of its parasitoid Mesoleius tenthredinis
Morley by encapsulation, with the deposition of phagocytic capsules around
the embryos. Therefore, the non-susceptible host race displaced the
susceptible host race. In some species encapsulation of diploid eggs and not
haploid eggs occurs. Evidence exists that formerly susceptible
host populations may become resistant to parasitoid attack. Cases are also
known where otherwise normal hosts are rendered unsuitable by the host plants
on which the host develops. The host plant may confer on the host insect
a kind of immunity to parasitization (Flanders 1953, J. M. Smith 1957). Habrolepis rouxi Compere suffers very little mortality of its
immature stages when attacking Aonidiella
aurantii (Maskell) on
grapefruit; however, when the scale is grown on sago palm, 100% mortality of
immature H. rouxi occurs. Smith reported
this same phenomenon with Comperiella
bifasciata Howard. In a slightly different context, there are
unpublished observations by workers at the University of California,
Riverside and the U. S. Department of Agriculture in Texas that citrus trees
which have received treatments of DDT or other insecticides actually change
their nutritional value to favor pest insect species thereon. Scale insects
were stimulated to reproduce and grow at a faster rate. Parasitoids were also
eliminated by the treatments so that the host's increase was unchecked for
some time following a treatment. The so-called "DDT check
method" to exclude the activity of natural enemies, therefore, may give
distorted data on the actual value of the parasitoids and predators
eliminated because the hosts are artificially stimulated. In summary, host habitat finding is
important to the success or failure of natural enemies in regulating their
host populations. During host searching, parasitoids often search first for
the environment frequented by the host. Odor associated with these habitats
is usually the attracting force. Host visibility only aids the parasitoid in
pinpointing an object which has already exerted an attraction. Many parasitic
Hymenoptera will oviposit in any suitable insect located in the favored
habitat, the host plant occasionally being more attractive to the parasitoid
than the host itself. Honeydew produced by aphids and coccids also can
attract parasitoids. Moisture in the form of dew is required by many
parasitic species. Locomotion of the parasitoid may determine
the extent to which the host habitat is selected and frequented. Phytophagous
hosts are sometimes rendered immune to successful parasitization by certain
plants upon which they feed. The plant on which the host is feeding may
affect host selection, fecundity and longevity of the parasitoid. Host
Regulation This fifth category in the host selection
process was proposed by Bradleigh Vinson of Texas A. & M. University to
account for cases in which parasitism changes the host physiologically, causing
it to behave in a different manner (Vinson 1976). It does not have anything
to do with "regulation" of host numbers. Manner
and Place of Oviposition Obviously those species that oviposit merely
in the vicinity of hosts or randomly within their host's general habitat are
not exercising as much discrimination as those parasitoids in which
host-selection behavior is developed to the degree where a specific host
organ or location on a host serves as the oviposition site. Many species of Diptera and a few parasitic
Hymenoptera, oviposit in habitats frequented by their hosts, but apart from
any host individuals that may be present. These parasitoids may lay their
eggs more or less at random upon plant foliage or other plant parts, and host
contact is made when those eggs are subsequently ingested by their
plant-feeding hosts. The eggs of some Hymenoptera hatch into small, motile
larvae which usually can live without food for long periods of time and which
attach themselves to passing host individuals. Some dipterous parasitoids are
viviparous with the eggs hatching within the parasitoid female that
subsequently larviposit within the vicinity of, but apart from, their hosts. The eggs of many species of dipterous and
hymenopterous parasitoids are deposited on the host. The larvae, after
hatching, variously feed either externally as ectoparasitoids or enter the
host and develop as endoparasitoids. The eggs of such parasitoids may either
be glued to the host integument or anchored in place by peg-like extensions of
the chorion which penetrate the host's integument. It can generally be said that hosts living
in exposed situations, such as leaf-skeletonizing larvae, tend to be attacked
by endoparasitoids; whereas, hosts living in protected situations, such as
galls, tunnels, galleries, mines, or in puparia or cocoons, tend to be
attacked by ectoparasitoids. It follows that parasitoids of exposed hosts
generally oviposit within their hosts. These eggs may simply be thrust into
the host's haemocoel and left to float free in the blood, or the eggs may be
inserted into specific host organs. Exercise 13.1--Discuss how the character of the host
habitat may influence natural enemy activity. How could this knowledge be
useful in (1) foreign exploration and (2) in evaluation of natural enemy
activity? Exercise 13.2--What are some characteristics of the
habitat that attract or repel natural enemies? Exercise 13.3--What are the processes in host selection? Exercise 13.4--How may insecticide applications alter the
host habitat? REFERENCES: [Additional references may be found at
MELVYL Library ] Altieri, M. A. et al. 1982. Effects
of plant extracts on the rates of parasitization of Anagasta kuehniella
(Lep.: Pyralidae) eggs by Trichogramma
pretiosum (Hym.:
Trichogrammatidae) under greenhouse conditions. Entomophaga 27: 431-38. Arthur, A. P. 1962. Influence
of host tree on abundance of Itoplectis
conquisitor (Say)
(Hymenoptera: Ichneumonidae), a polyphagous parasite of the European pine
shoot moth, Ryacionia buoliana (Schiff) (Lepidoptera:
Olethreutidae). Canad. Ent. 94: 337-47. Arthur,
A. P., B. M. Hedgekak & L. Rollins. 1969. Component of the host
haemolymph that induces oviposition in a parasitic insect. Nature (London)
223: 966-7. Beevers,
M. et al. 1981. Kairomones and their use for management of entomophagous
insects. X. Laboratory studies on manipulation of host-finding behavior of Trichogramma pretiosum Riley with a
kairomone extracted from Heliothis
zea (Boddie) moth scales. J.
Chem. Ecol. 7: 635-48. Beirne, P. B. 1962. Trends
in applied biological control of insects. Ann. Rev. Ent. 7: 387-400. Bellows,
T. S., Jr. & T. W. Fisher, (eds) 1999. Handbook of Biological Control:
Principles and Applications. Academic Press, San Diego, CA. 1046 p. Boller, E. 1972. Behavioral
aspects of mass rearing of insects. Entomophaga 17: 9-25. Bombosch, S. 1966. Behaviour
of aphidophagous insects. In:
Proc. Symp. "Ecology of Aphidophagous Insects," Liblice, 1965. Academia, Prague. p. 111. Bouchard,
Y. & C. Cloutier. 1985. Role of olfaction in host finding by aphid
parasitoid Aphidius nigripes (Hymenoptera:
Aphidiidae). J. Chem. Ecol. 11: 801-08. Chandler,
A. E. F. 9166. Some aspects of host plant selection in aphidophagous
Syrphidae. In: Proc. Symp.
"Ecology of Aphidophagous insects." Liblice 1965. Academia, Prague. p.
113-15. Chandler,
A. E. F. 1967. Oviposition responses by aphidophagous Syrphidae (Diptera). Nature 213: 736. 204. Chiri, A. A. & E. F. Legner. 1982. Host-searching kairomones alter behavior
of Chelonus sp. nr. curvimaculatus, a hymenopterous
parasite of the pink bollworm, Pectinophora
gossypiella (Saunders). Environ. Entomol. 11(2): 452-455. 208. Chiri, A. A. & E. F.
Legner. 1983. Field applications of host-searching kairomones
to enhance parasitization of the pink bollworm (Lepidoptera:
Gelechiidae). J. Econ. Entomol. 76(2):
254-255. 225. Chiri, A. A. & E. F. Legner. 1986. Response of three Chelonus (Hymenoptera: Braconidae) species to kairomones in
scales of six Lepidoptera. Canad. Entomol. 118(4): 329-333. Clausen, C. P. 1962. Entomophagous
Insects. 2nd ed. Hafner Publ. Col, New York. 688 p. Collyer,
E. 1958. Some insectary experiments with predacious mites to determine the
effect on the development of Metatetranychus
ulmi (Koch) populations.
Entomol. Exp. & Appl. 1: 138-46. Cushman,
R. A. 1926. Location of individual hosts versus systematic relation of host species
as a determining factor in parasitic attack. Proc. Ent. Soc. Wash. 28: 5-6. Davis,
G. C. 1896. Pests of house and ornamental plants. Mich. Agr. Expt. Sta. Bull. 2: 3-45. DeBach, P. 1944. Environmental
contamination by an insect parasite and the effect on host selection. Ann. Ent. Soc. Amer. 37: 70-74. DeBach, P., C. A. Fleschner & E. J.
Dietrick. 1949. California red
scale studies and possible control by employment of natural enemies. Calif.
Agric. 3: 12-15. DeLoach,
C. J. 1970. The effect of habitat diversity on predation. Proc. Tall Timbers
Conf. on Ecol. Animal Control by Habitat Management (2): Feb 26-28,
Tallahassee, Fla. p. 223-41. Dicke,
M., J. C. van Lenteren, G. J. F. Boskamp & R. van Voorst. 1985.
Intensification and prolongation of host searching in Leptopilina heterotoma
(Thomson) (Hymenoptera: Eucoilidae) through a kairomone produced by Drosophila melanogaster. J. Chem. Ecol. 2: 125-36. Doutt,
R. L. 1959. The biology of parasitic Hymenoptera. Ann. Rev. Ent. 4: 141-82. Doutt,
R. L. 1965. Biological characteristics of entomophagous adults. In: P. DeBach (ed.),
"Biological Control of Insect Pests and Weeds." 2nd ed., W. Clowes
& Sons, London. p. 152. Downing,
R. S. & T. K. Moilliet. 1967. Relative densities of predacious and phytophagous
mites on three varieties of apple trees. Canad. Ent. 99: 738-41. Dusek,
J. & P. Laska. 1966. Occurrence of syrphid larvae on some aphids. In: Proc. Symp. "Ecology
of Aphidophagous Insects." Liblice, 1965. Academia, Prague. p. 37-8. Edwards,
R. L. 1954. The host-finding and oviposition behavior of Mormoniella vitripennis
(Walker) (Hym., Pteromalidae), a parasite of muscoid flies. Behavior 7:
88-112. Eikenbary,
R. D. & C. E. Rogers. 1973. Importance of alternate hosts in
establishment of introduced parasites. Proc. Tall Timbers Conf. Ecol. Anim.
Contr. & Habitat Management 5: 119-33. 264. Etzel, L. K. & E. F. Legner. 1999.
Culture and Colonization. In: T. W. Fisher & T. S. Bellows, Jr. (eds.), Chapter 15, p.
125-197, Handbook of Biological Control:
Principles and Applications.
Academic Press, San Diego, CA
1046 p. Flanders, S. E. 1935. An
apparent correlation between the feeding habits of certain pteromalids and
the condition of their ovarian follicles. Ann. Ent. Soc. Amer. 28: 438-44. Flanders, S. E. 1937. Habitat
selection by Trichogramma. Ann. Ent. Soc. Amer. 30: 208-210. Flanders, S. E. 1940. Environmental
resistance to the establishment of parasitic Hymenoptera. Ann. Ent. Soc. Amer. 33: 245-53. Flanders, S. E. 1942. Abortive
development in parasitic Hymenoptera induced by the food plant of the insect
host. J.
Econ. Ent. 35: 834-35. Flanders, S. E. 1953. Variations
in susceptibility of citrus-infesting coccids to parasitization. J. Econ. Ent. 46: 266-69. Fleschner, C. A. & G. T. Scriven. 1957.
Effect of soil-type and DDT on ovipositional response of Chrysopa californica
(Coq.) on lemon trees. J.
Econ. Ent. 50: 221-22. Franklin, R. D. & F. G. Holdaway. 1966.
A relationship of the plant to parasitism of European corn borer by the
tachinid parasite Lydella griscences. J. Econ. Ent. 59: 440-41. Gahan, A. B. 1933. The
serphoid and chalcidoid parasites of the Hessian fly. U. S. Dept. Agric.
Misc. Pub. 174. Gardner,
S. M. & J. C. van Lenteren. 1986. Characterization of the arrestment
responses of Trichogramma evanescens. Oecologia 68: 265-70. Gilmore, J. U. 1938. Notes
on Apanteles congregatus (Way) as a parasite
of tobacco hornworms. J.
Econ. Ent. 31: 712-15. 265. Gordh, G., E. F. Legner & L. E.
Caltagirone. 1999. Biology of parasitic Hymenoptera. In: T. W. Fisher & T. S. Bellows, Jr.
(eds.), Chapter 15, p. 355-381, Handbook
of Biological Control: Principles and
Applications. Academic Press, San
Diego, CA 1046 p. Graham, S. A. & L. G. Baumhoffer. 1927.
The pine tip moth in the Nebraska National Forest. J. Agric. Res. 35: 323-33. Greany,
P. D. & E. R. Oatman. 1972. Demonstration of host discrimination in the
parasite Orgilus lepidus (Hymenoptera:
Braconidae). Ann.
Ent. Soc. Amer. 65: 375-6. Gross,
H. R., Jr., et al. 1975. Kairomones and their use for management of
entomophagous insects: III. Stimulation of Trichogramma achaeae,
T. pretiosum, and Microplitis
croceipes with host-seeking
stimuli at time of release to improve their efficiency. J. Chem. Ecol. 1:
431-38. Hagen, K. S., E. F. Sawall, Jr., & R.
L. Tussan. 1970. The use of food
sprays to increase effectiveness of entomophagous insects. Proc. Tall Timbers
Conf. Ecol. Anim. Contr. Habitat Management 2: 59-81. Herrebout,
W. M. 1969. Some aspects of host selection in Eucarcelia rutilla
Vill. (Diptera: Tachinidae). Neth. J. Zool. 19: 1-104. Hodek,
I. 1966. Food ecology of aphidophagous Coccinellidae. In: Proc. Symp. "Ecology of Aphidophagous
Insects," Liblice, 1965. Academia, Prague. p. 23-30. Iperti,
G. 1966. Specificity of aphidophagous Coccinellidae in south eastern France. In: Proc. Symp. "Ecology
of Aphidophagous Insects," Liblice, 1965. Academia, Prague. p. 31-4. Jones,
R. L., W. J. Lewis, M. C. Bowman, B. Beroza & B. A. Bierle. 1971.
Host-seeking stimulant for parasite of corn earworm: isolation,
identification and synthesis. Science (Wash., D.C.) 1973: 872-3. King,
P. E. & J. Rafai. 1970. Host discrimination in a gregarious parasitoid, Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae). J. Exp.
Biol. 53: 245-54. Klausmitzer,
B. 1966. Relation of different species of Coccinellidae to the habitat of fir
forests. In: Proc. Symp.,
"Ecology of Aphidophagous Insects," Liblice, 1965. Academia, Prague. p. 165-66. Kulman,
H. M. & A. C. Hodson. 1961. Parasites of the jack pine budworm, Choristoneura pinnus, with special reference
to parasitism at particular locations. J. Econ. Ent. 54: 221-24. Laing,
J. 1937. Host-finding by insect parasites. 1. Observations on the finding of
hosts by Alysia manducator, Mormoniella vitripennis and Trichogramma evanescens. J. Anim. Ecol. 6(2): 298-317. Lawson,
F. R. 1959. The natural enemies of the hornworms on tobacco (Lepidop. Sphyngidae). Ann. Ent. Soc. Amer. 52:
741-55. 46. Legner, E. F. 1967. Behavior changes the reproduction of Spalangia cameroni, S. endius, Muscidifurax raptor,
and Nasonia vitripennis (Hymenoptera: Pteromalidae) at increasing
fly host densities. Ann. Entomol.
Soc. Amer. 60(4): 819-826. 59. Legner, E. F. 1969a. Distribution
pattern of hosts and parasitization by Spalangia
drosophilae (Hymenoptera:
Pteromalidae). Canad. Entomol. 101(5): 551-557. 57. Legner, E. F. 1969b. Adult emergence interval and reproduction
in parasitic Hymenoptera influenced by host size and density. Ann. Entomol. Soc. Amer. 62(1): 220-226 167. Legner, E. F. & S. N. Thompson. 1977.
Effects of the parental host on host selection, reproductive
potential, survival and fecundity of the egg-larval parasitoid Chelonus sp. near curvimaculatus, reared on Pectinophora
gossypiella and Phthorimaea operculella. Entomophaga 22(1): 75-84. Leong, J. K. L. 1966. The
biology of Campoplex haywardi Blanchard
(Hymenoptera: Ichneumonidae), a primary parasite of the potato tuberworm. M.
S. Thesis, Univ. of California, Riverside. 63 p. Lewis,
W. J., A. N. Sparks & L. M. Redlinger. 1971. Moth odor: a method of
host-finding by Trichogramma
evanescens. J. Econ. Ent. 64: 557-8. Lewis,
W. J., R. L. Jones & A. N. Sparks. 1972. A host-seeking stimulant for the
parasite Trichogramma evanescens: its source and a
demonstration of its laboratory and field activity. Ann. Ent. Soc. Amer.
65: 1087-89. Madden,
J. 1968. Behavioral responses of parasites to the symbiotic fungus associated
with Sirex nictilio F. Nature (London)
218: 189-90. McLeod, J. H. 1951. Notes
on the lodgepole needle miner, Recurvaria
milleri Busck. (Lep.:
Gelechiidae), and its parasites in western North America. Canad. Ent. 83:
295-301. Milliron,
H. E. 1940. A study of some factors affecting the efficiency of Encarsia formosa Gahan, an aphelinid parasite of the greenhouse
whitefly, Trialeurodes vaporarium (Westw.). Mich.
Agric. Expt. Sta. Tech. Bull. 173: 1-23. Monteith,
L. G. 1955. Host preferences of Drino
bohemica Messn. (Diptera: Tachinidae)
with particular reference to olfactory responses. Canad. Ent. 87: 509-30. Monteith,
L. G. 1960. Influence of plants other than the food plants of their host on
host finding by tachinid parasites. Canad. Ent. 92: 641-52. Monteith,
L. G. 1964. Influence of the health of the food plant of the host on host
finding by tachinid parasites. Canad. Ent. 96: 1477-81. Monteith,
L. G. 1966. Influence of new growth on the food plant of the host on
host-finding by Drino bohemica Messn. (Diptera: Tachinidae). Canad. Ent.
98: 1205-07. Monteith,
L. G. 1967. Responses by Diprion
hercyniae (Hym.:
Diprionidae) to its food plant and their influence on its relationship with
its parasite Drino bohemica (Diptera: Tachinidae).
Canad. Ent. 99: 682-85. Nishida,
T. 1956. An experimental study of the ovipositional behaviour of Opius fletcheri Silvestri (Hym: Braconidae), a parasite of the
melon fly. Proc. Hawaiian Ent. Soc. 16: 126-34. Noldus, L. P. & J. C. van
Lenteren. 1983. Kairomonal
effects on host searching of Trichogramma
evanescens an egg parasite
of Pieris brassicae. Med. Fac. Landbouw. Rijks. Univ. 48(2): 193-194. Noldus, L. P. & J. C. van
Lenteren. 1985. Kairomones for
the egg parasite Trichogramma
evanescens Westwood. I.
Effect of volatile substances released by two of its hosts, Pieris brassicae L. and Mamestra
brassicae L. J. Chem. Ecol. Parker,
J. R. 1918. The life history and habits of Chlorpisca glabra
Meig., a predaceous chloropid. J. Econ. Ent. 11: 368-80. Phillips,
W. J. & G. W. Barber. 1933. Egg laying habits and fate of eggs of the
corn earworm moth, and factors affecting them. Virginia St. Tech. Bull. 47:
1-14. Picard,
F. & E. Rabaud. 1914. Sur le parasitism externe des Braconids (Hym.).
Bull. Ent. Soc. France 19: 266-69. Pichersky,
E. 2004. Plant Scents. Amer.
Scientist 92: 514-21. Price,
P. W. 1970. Trail odors: recognition by insects parasitic in cocoons. Science
(Washington, D.C.) 170: 546-47. Putman, W. L. & D. H. Herne. 1966.
The role of predators and other biotic agents in regulating the population
density of phytophagous mites in Ontario peach orchards. Canad. Ent. 98: 808-20. Quednau, F. W. & H. M. Hubsch. 1964.
Factors influencing the host-finding and host acceptance pattern in some Aphytis species (Hym: Aphelinidae).
S.
Africa J. Agr. Sci. 7: 543-54. Rabb,
R. L. & J. R. Bradley. 1968. The influence of host plant on parasitism of
eggs of the tobacco hornworm. J. Econ. Ent. 61: 1249-52. Richards,
O. W. 1940. The biology of the small white butterfly (Pieris rapae),
with special reference to the factors controlling its abundance. J. Anim. Ecol. 9: 243-88. Richerson, J. V. & L. J. DeLoach. 1972.
Some aspects of host selection of Perilitus
coccinellae. Ann. Ent. Soc. Amer. 65: 834-9. Richerson, J. V. & J. H. Borden. 1972.
Host-finding by heat perception in Coeloides
brunneri (Hymenoptera:
Braconidae). Canad. Ent. 104: 1877-81. Salt,
G. 1935. Experimental studies in insect parasitism. 3. Host selection. Proc.
Roy. Soc. B. 117: 413-35. Salt,
G. 1958. Parasitic behaviour and the control of insect pests. Endeavour 17:
145-48. Seamans,
H. L. & E. McMillan. 1935. The effect of food plants on the development
of the pale western cutworm (Agrotis
orthogonia Morr.). J. Econ.
Ent. 28: 421-25. Simmonds,
H. W. 1944. The effect of the host fruit upon the scale Aonidiella aurantii
Mask. in relation to its parasite Comperiella
bifasciata How. J.
Australian Inst. Agric. Sci. 10: 38-9. Skuhravy,
V. & K. Novak. 1966. Migration of coccinellids to the sugar beet fields
during the influx of Aphis fabae Scop. In: Proc. Symp. "Ecology
of Aphidophagous Insects." Liblice, 1965. Academia, Prague. p. 167-69. Smith,
H. S. 1949. A race of Comperiella
bifasciata successfully
parasitizes California red scale. J. Econ. Ent. 35: 809-12. Smith,
J. M. 1957. Effects of the food plant of California red scale, Aonidiella aurantii (Mask.) on reproduction of its hymenopterous
parasites. Canad. Ent. 89: 219-30. Smits,
P. H. 1982. The influence of kairomones of Mamestra brassicae
L. on the searching behaviour of Trichogramma
evanescens Westwood. Proc.
Int. Symp. Trichogrammes
1: 139-50. Sol, R. 1966. The
occurrence of aphidivorous syrphids and their larvae on different crops, with
the help of coloured water traps. In:
Proc. Symp., "Ecology of Aphidophagous Insects." Liblice, 1965. Academia, Prague. p.
181-84. Speyer,
E. R. 1929. The greenhouse whitefly. J. Roy. Hort. Soc. 54: 181-92. Spradberry, J. P. 1970. Host-finding
by Rhyssia persuasoria, an ichneumonid
parasite of siricid woodwasps. Anim. Beahv. 18: 103-14. Stary,
P. 1964. Food specificity in the Aphidiidae (Hymenoptera). Entomophaga 9:
92-9. Tamaki,
G. & R. E. Weeks. 1968. Anthocoris
melanocerus as a predator of
the green peach aphid on sugar beets and broccoli. Ann. Ent. Soc. Amer.
61: 579-84. Thompson,
W. R. 1957. The specificity of host relations in predacious insects. Canad.
Ent. 83: 262-29. Thorpe,
W. H. 1939. Further studies on pre-imaginal olfactory conditioning in
insects. Proc. Roy. Soc. (B) 127: 424-33. Thorpe,
W. H. & H. B. Caudle. 1938. A study of the olfactory responses of insect
parasites to the food plant of their host. Parasitology 30: 523-28. Thorpe,
W. H. & F. G. Jones. 1937. Olfactory conditioning in a parasitic insect and
its relation to the problem of host selection. Proc. Roy. Soc. (B) 124:
56-81. Ullyett,
G. C. 1949. Pupation habits of sheep blowflies in relation to parasitism by Mormoniella vitripennis Wlk. (Hym.,
Pteromalidae). Bull. Ent. Res. 40: 533-37. van
Alphen, J. M. M. & L. E. M. Vet. 1986. An evolutionary approach to host
finding and selection. In:
J. Waage & D. Greathead (eds.). Insect
Parasitoids. Academic Press,
London. p. 23-61. van
Steenburgh, W. E. 1934. Trichogramma
minutum Riley as a parasite
of the oriental fruit moth (Laspeyresia
molesta Busck) in Ontario.
Canad. J. Res. 10: 287-314. Vet,
L. E. M. 1983. Host-habitat location through olfactory cues by Leptopilina clavipes (Hartig) (Hym.:
Eucoilidae), a parasitoid of fungivorous Drosophila:
The influence of conditioning. Neth. J. Zool. 33: 222-248. Vet,
L. M. 1985. Response to kairomones by some alysiine and eucoilid parasitoid
species (Hymenoptera). Neth. J. Zool. 35: 486-96. Vet,
L. E. M. & K. Bakker. 1985. A comparative functional approach to the host
detection behaviour of parasitic wasps. 2. A quantitative study of eight
eucoilid species. Oikos 44: 487-98. Vet,
L. E. M. & J. J. M. van Alphen. 1985. A comparative functional approach
to the host detection behaviour of parasitic wasps. 1. A qualitative study on
Eucoilidae and Alysiinae. Oikos
44: 478-86. Vet, L. E. M. & R. van der Hoeven. 1984.
Comparison of the behavioral response of two Leptopilina species (Hymenoptera: Eucoilidae), living in
different microhabitats, to kairomones of their host (Drosophilidae). Neth.
J. Zool. 34: 220-27. Vet, L. E. M. et al. 1984. Microhabitat
location and niche segregation in two sibling species of drosophilid
parasitoids: Asobara tabida (Nees) and A. rugescens (Foerster) (Braconidae: Alysiinae). Oecologia 61: 182-88. Vinson, S. B. 1968. Source
of a substance in Heliothis virescens (Lepidoptera:
Noctuidae) that elicits a searching response in its habitual parasite, Cardiochiles nigriceps (Hymenoptera:
Braconidae). Ann.
Ent. Soc. Amer.
61: 8-10. Vinson, S. B. 1975. Source
of a material in the tobacco budworm which initiates host-searching by the
egg-larval parasitoid, Chelonus
texanus. Ann. Ent. Soc. Amer. 68: 381-84. Vinson, S. B. 1976. Host
selection by insect parasitoids. Ann. Rev. Ent. 21: 109-133. Weseloh, R. M. 1969. Biology
of Cheiloneurus noxius, with emphasis on host
relationships and oviposition behavior. Ann. Ent. Soc. Amer. 62: 299-305. Weseloh, R. M. 1971a. Influence
of host deprivation and physical host characteristics on host selection
behavior of the hyperparasite Cheiloneurus
noxius (Hymenoptera:
Encyrtidae). Ann.
Ent. Soc. Amer. 64: 580-86. Weseloh, R. M. 1971b. Influence
of primary (parasite) hosts on host selection of the hyperparasite Cheiloneurus noxius (Hymenoptera:
Encyrtidae). Ann.
Ent. Soc. Amer. 64: 1233-36. Weseloh, R. M. 1972. Sense
organs of the hyperparasite Cheiloneurus
noxius (Hymenoptera:
Encyrtidae) important in host selection processes. Ann. Ent. Soc. Amer. 65: 41-6. Weseloh, R. M. 1974. Host
recognition by the gypsy moth larval parasitoid, Apanteles melanoscelus.
Ann.
Ent. Soc. Amer. 67: 585-7. Weseloh, R. M. & J. F. Anderson. 1975.
Inundative release of Apanteles
melanoscelus against the
gypsy moth. Environ.
Ent. 4: 33-36. Weseloh, R. M. & B. R. Bartlett. 1971.
Influence of chemical characteristics of the secondary scale host on host
selection behavior of the hyperparasite Cheiloneurus
noxius (Hymenoptera:
Encyrtidae). Ann.
Ent. Soc. Mer. 64: 1259-64. Williams,
R. N. & W. H. Whitcomb. 1973. Parasites of fire ants in South America.
Proc. Tall Timbers Conf. Ecol. Anim. Control Habitat Management 5: 49-59. Wilson,
D. D., R. L. Ridgway & S. B. Vinson. 1974. Host acceptance and
oviposition behavior of the parasitoid Campoletis
sonorensis (Hymenoptera:
Ichneumonidae). Ann.
Ent. Soc. Amer. 67: 271-4. Wylie, H. G. 1958. Factors
that affect host finding by Nasonia
vitripennis (Walk.) (Hymenoptera: Pteromalidae). Canad. Ent. 90: 597-608. Zwolfer, H. & M. Kraus. 1957.
Biocoenotic studies on the parasites of two fir and two oak tortricids.
Entomophaga 2: 173-96 |