Augmentation of Natural Enemies Pages 159178

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Augmentation of Natural Enemies (Pages 159-178)
Augmentation can involve native or introduced
natural enemies. Underlying considerations are
the same as for conservationAgents are
potentially effective, but constrained by
environ., absent from crop, too scarce, too
lateOther control options too costly or too
disruptive. Tactics Food sprays
Supplemental releases The idea originated in
about 1910 in California, it has been used more
extensively in other countries than in the US.
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Augmentation of Natural Enemies (Pages 159-178)
Food sprays (Page 159) Food sprays rarely fall
into the category of augmentation.They must
increase agent reproduction to fit here. The
prominent exception is Ken Hagens work with
protein-rich food sprays and the green lacewing
Chrysoperla plorabunda. Chrysoperla
plorabunda
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Augmentation of Natural Enemies (Pages 159-178)
Food sprays (Page 159) Chrysoperla plorabunda
responds to protein rich food sprays,(artificial
honeydew) (see graphs on page 167)
Aggregation attracted to odor of indole
acetaldehyde Increased oviposition protein in
diet supports increased oogenesis (recall
symbiotic yeasts in crop)
Adults/100 sweeps
Eggs/25 stems
200
cut
cut
10
.
Sample data
control treatment
0
0
Time
Time
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
160) Augmentative releases directly increase the
number of agents present. They are expected to
be repeated periodically rather than to establish
the natural enemy in the field. Many species
have been used in augmentative biological
control.See the list of examples on pages 168
169 predaceous mites, Phytoseidae predaceous
insects, Chrysopidae, Coccinellidae,
etc. Parasitic insects, Aphelinidae,
Trichogrammatidae, etc.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
160) Agents may be collected, reared or
purchased. Collecting is cheap, when it is
easy and efficient. Purchasing agents can be
easy, but costly and quality(?) Rearing may
or may not be possible, takes work, may be
expensive.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
160) Releases may be inoculative or
inundative. Inoculative releases fewer natural
enemies needed earlier in season/pest
increase progeny will control the pest
population may require supplementing
pest pop. Inundative releases more (many)
natural enemies needed when pest is
abundant released agents control pest
pop. Both have advantages and disadvantages.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
160) Inoculative releases Avoid rearing/buying
huge numbers of agents, saves time and
money Agent may not persist in field until
pest pop. increases, may need a second
(inundative?) releaseInundative releases Agent
will be present when and where it is
needed. Large numbers of agents are expensive
to rear or buy.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
160) Beginning a project Considerations are
like those for conservation Basic
questions Are potentially effective agents
present in the crop? Are potentially effective
agents available elsewhere?
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Augmentation of Natural Enemies (Pages 159-178)
Beginning a project (Pages 160 161) 1.
Sample local entomophage community 2. Determine
entomophage species present 3. Recognize
potentially effective agents 4. Determine if
pest is amenable to inoc./inund. BC 5.
Determine if agent is amenable to use in
releases 6. Can agent be reared
economically 7. Can agent be purchased
economically 8. Develop means to hold agents
until needed 9. Develop a system for releasing
agents 10. Evaluate the program
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
161) Beginning a project 1. Sample local
entomophage community 2. Determine entomophage
species present 3. Recognize potentially
effective agents These steps are the same as in
conservation BC. If a potentially effective
agent is present, a food spray could be
beneficial for conservation and/or
augmentation. If no effective agent is present
and augmentable by feeding, you move to
considering releases.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
161) 4. Is the pest amenable to inocualtive or
inundative releases? Does the pest
population build up slowly and dependably?
Does the pest population explode
erratically? In the first case, inoculative
releases are feasible. In the second, you
probably need inundative releases. Having
agents available at the critical moment is a
challenge.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
161) 5. Is the agent amenable to inoculative or
inundative releases? A. What is the
agents abundance pattern in the field?
The common problem is absence/scarcity in early
season. Is it because of low overwintering
survival? Inoculation may work. May
inoculate pest too. Does the agent require
high prey densities? May require inundative
releases.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
161) 5. Is the agent amenable to inoculative or
inundative releases? B. What is the
agents capability to kill pests? Higher
consumption rates facilitate inundative
releases. Higher consumption rates permit
delaying inoculative releases. C. What is the
agents reproductive potential? Higher
fecundity increases numerical response, facilita
tes inoculative releases, permits delayed
inoculative releases
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
162) 6. Can agents be reared economically? A.
Are other species in the genus/family being
reared? If so, you have a starting point. B.
If you need host/prey, can it be reared
economically? Can host be reared
reliably? Do epizootics occur, sensitivity to
RH, etc. If rearing host is costly, consider
inoculative releases artificial diet C.
Artificial diet development is a specialized
activity. Start with diets for related taxa,
modify from there. If good, artificial diet
cheaper and more reliable. (See page 165)
Biologixs story
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
162) 7. Can agents be purchased economically?
Often expensive Can augment existing nat.
en. populations Can introduce a new
agent Quality control concerns Are you getting
the right agent? Are you getting
healthy agents? We will look at these later.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
162) 8. Develop a system to hold agents Any
storage capability is good, deals with
asynchronies Can be easy, e.g. purchased
Hippodamia convergens, in diapause, keep cool
give some water Can be hard, e.g. reared agent
without diapause 9. Develop a system for
releasing agents Timing issues, as in classical
biological control How can you distribute the
agents throughout the field? Sprinkle lacewing
eggs, high mortality Set out mite envelopes,
labor intensive Hang Trichogramma release
houses How can we scale up for huge releases?
Planes?
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
162) 10. Evaluate the program Compare
fields with and without releases Variability
great, need many replicates Inclusion
cages Easy, include sham cages Can get many
replicates Can test multiple release
densities Cage effects inescapable
Exclusion cages Not used as frequently
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
162) 10. Evaluate the program Examples (Pages
170-172) Some show good control, e.g.
92 Many used very high release rates, e. g.
100,000 Podisus maculiventris (Hemiptera
Pentatomidae) per acre, difficult and expensive
to rear No two are comparable Different
pests, different agents, different densities
Podisus feeding on prey
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
163) Earliest example Mealybug destroyer,
Cryptolaemus montrouzieri (Coleoptera
Coccinellidae)Introduced into California
1892Established along southern coast, died out
in winter in other areasCollection and
reintroductions began about 1910Insectary built
in 1916, 14 insectaries by 1931
(Growers) Produced up to 40,000,000 C.
montrouzieri per year
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
163) Parasites were also produced by grower
cooperatives. One example Leptomastix dactylopii
and Pauridia peregrina(Hymenoptera Encyrtidae)
cultured and releasedduring the 1950s. Helped
control citrus mealybug, Pseudococcus citri.
Numerous other scale parasites were also
reared.
Leptomastix on mealybugs
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
163) Current trends Trichogramma spp. used
extensively worldwide (see pages 168
169) Greatest use in Russia and China Vast
agriculture Low-cost labor for rearing
efforts Large-scale applications at high
densities
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
163) Chinese system Giant silk moth
(Saturniidae) caterpillars reared on
foliage Pupae sexed Some reared to maintain
colony Most males discarded or eaten Most
females (pro-oogenic) broken openEggs washed,
dried, exposed to TrichogrammaParasitized eggs,
put into field release containers (little
plastic pagodas with windows)Release containers
hung in trees, wasps emerge
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Hippodamia
convergensHarvested from diapause sites, sold
Dispersal problems
Hippodamia convergens aggregation
Hippodamia convergens adult
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Chrysoperla plorabunda
and C. rufilabrisEasily reared, adults
glycinophagousArtificial diets for larvae
(cannibalistic, so isolated)Sold as eggs or
pupaeCan be effective, but costly, and quality
control problems
cloth top for oviposition
.
.
.
.
.
comb for eggsto pass through
Cloth removed, egg stalks cut, eggs scattered
into rearing chambers, larvae fed,pupae
returned to adult chamber
roll of cloth
adult lacewings
cage wall
food and water
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Predaceous mites
Increasing in use Improved rearing still
based on natural foodsImproved shipping and
release systems envelopes with substrate, to
place in plants
Phytoseid mite consuming a spider mite
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Predaceous Hemiptera
Anthocoridae and Geocoris Increasing in use
Improved rearing artificial diets developed
Orius sp.Hemiptera Anthocoridae
Geocoris sp.Hemiptera Lygaeidae
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Parasitic wasps
Nasonia spp. (Hymenoptera Pteromalidae)Used in
livestock productionControl filth/dung flies,
e.g. Muscidae
Nasonia sp. antennating a fly puparium
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Pages
163-164) Uses in the US Parasitic wasps
Encarsia formosa (Hymenoptera Aphelinidae)
Used in greenhouses Controls greenhouse
whitefly, Trialeurodes vaporariorum
Greenhouse whitefly(Homoptera Aleurodidae)
Encarsia formosa ovipositing in greenhouse
whitefly nymph
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
164) Greenhouses/Glasshouses Most extensive use
of augmentative releasesConfined space, agents
cannot leaveHigh value crops, so can afford
agentsChemical control undesirable for many
products, e. g. VegetablesChemicals,
especially sprays, dangerous for all
employees Europeans, especially the Dutch, are
far ahead of the US in this area of work. They
grow more crops in glasshouses and are more
attuned to organic foods.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
165) Quality control issues in commercial
insectariesMany species are reared and sold (See
pages 16- ) Common Problems 1. Proper
identificationsNasonia/Muscidifurax spp.,
Trichogramma spp., Chrysoperla spp. Wrong
species may not attack target pest (e.g.
Nasonia) suit target habitat
(e.g. Tricho.) Could introduce a species
outside its native range
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
165) Quality control issues in commercial
insectaries 2. Quality control in mass rearing
Many things can go wrong in rearing and
shipping insects Contaminated diet may yield
non-viable pupae Wrong photoperiod could
induce diapause Too hot/cold could increase
mortality Improper packaging, e.g. too moist
or too dry, can increase mortality (recall
classical BC discussion)
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
165) Quality control issues in commercial
insectaries 3. Guidelines for holding and
release Quality of the information
provided varies enormously, from none to
very good Do the agents need water?
Should they be released in the morning?
Without information little chance of success.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
165) Quality control issues in commercial
insectaries Solutions are being
sought. Producers formed a national
organization. They are establishing
guidelines. They plan to certify insectaries.
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Augmentation of Natural Enemies (Pages 159-178)
Augmentative releases of natural enemies (Page
165) Disruption of Research Thus far limited to
biological control of weeds Commercial dealers
havefollowed scientists to release sites to
collect agents for sale trespassed on private
property to collect agents The bad response
seems to have diminished these activities.