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Introduction
BIOLOGICAL CONTROL:
- Peppers and tomatoes are not native to Florida – they were introduced. They are attacked by pests that are
native to Florida and whose food is related native plants (usually of the same plant family) and pests that
arrived from elsewhere.
- Beneficial insects to agricultural crop production include those that act as pollinators as well those that serve as
predators or parasites of pest insects.
- It is well known that pollinators are a necessary part of most fruit and vegetable production schemes.
- The presence of a natural population of biological control organisms can be maintained by any number of
production practices, including use of low risk pesticides and the introduction of additional flowering plants as
a nectar and pollen source.
- Habitat management to enhance biological control refers to
the establishment of environmental conditions amenable to
natural enemies that increase and sustain their populations
and improve their effectiveness in controlling pests.
- Population processes such as colonization, dispersal and
foraging movements of predators can be influenced by habitat
modifications.
- On farms, such dynamics of natural enemy populations can be
altered through management of within-field strips, cover crops,
field margins, hedgerows, fencerows, windbreaks, irrigation
or drainage ditches and roadside margins (Figures 1-3).
HABITAT MANAGEMENT:
Figure 1. Bigeyed bugs are commonly found on wild plant species. Photograph by: Lyle Buss.
Figure 2. Ryegrass can act as a habitat for biological control organisms as well as a windbreak between crop rows. Photograph by: Phyllis Gilreath.
Figure 3. Some weeds in border areas can provide a habitat for natural enemies to harbor between growing seasons. Photograph by: Eric Simonne.
Prepared by: Drs. Jennifer Gillett and Howard Frank
Three forms of biological control are generally recognized:
- Manipulative or Conservation Biological Control
- Classical or Inoculative Biological Control
- Augmentative Biological Control
Here is how they apply in pepper and tomato production in Florida.
- Native pests have native natural enemies such as
predatory mites, predatory stinkbugs, minute pirate
bugs, numerous species of parasitoid flies and small
parasitoid wasps.
- For much of the time these native natural enemies keep
the pests in check. However, these native natural
enemies are at a disadvantage in some situations.
CONSERVATION BIOLOGICAL CONTROL:
- Pests that have arrived from elsewhere are the normal
targets of classical biological control.
- These pests arrive without the specialist natural enemies
that hold them in check in their countries of origin.
CLASSICAL OR INOCULATIVE BIOLOGICAL CONTROL:
- Once natural enemies have been established, they need
attention just like native natural enemies.
- Plants that can provide beneficial insects with nectar
may help increase their numbers where their action is
required.
- There is no guarantee that classical biological control
attempts will be successful.
- Example: parasitoid wasp introduced and released
against pepper weevil has not yielded much control and
may not do so.
- Classical biological control research is a worthwhile
endeavor because when it works the results are free.
Figure 4. Larra bicolor, a parasitoid wasp, acts to pollinate while feeding on nectar. Photograph by: Lyle Buss.
Prepared by: Drs. Jennifer Gillett and Howard Frank
Problem: The adult beneficial flies and wasps typically need plant nectar for energy – if their favorite nectar plants are absent in a large field containing nothing but the crop plant they may function well around the edges but not in the middle of the field.
Solution: Plant their favorite nectar-source plants in windbreaks (in a typical production field) or as patches in an organic production field (Figure 4).
Problem: Broad-spectrum chemical insecticides are usually deadly to natural enemies. Solution: try not to kill the beneficial organisms.
Example: Pest mole crickets arrived a century ago in ship ballast from southern South America.
In the 1980s University of Florida researchers brought specialist natural enemies of mole crickets from South America, released them in Florida and established populations.
The intent was that these established populations should spread and eventually provide Florida-wide control of pest mole crickets.
The natural enemies were a fly, a wasp and a nematode. All are now present in many counties but none is yet known to be present in all counties, although given enough time they should get there.
Introduction
- Research needs to be done before the most appropriate plants and their optimal spacing is determined.
- Such plantings have been researched for other crops in European countries and they have proven highly effective.
- Use of the newer narrow-spectrum chemicals, minimization of use of chemicals, and appropriate timing of their use will help conserve natural enemies (See Table 1 on pg. 197).
Jones, G.A. and J.L. Gillett. 2005. Intercropping with sunflowers to attract beneficial insects in organic agriculture. Fla Entomologist. 88(1): 91-96.
Frank, J.H., T.R. Fasulo and D.E. Short 2002. MCricket: Alternative Methods of Mole Cricket Control. http://molecrickets.ifas.ufl.edu/ (28 June 2006).
Frank, J.H. and J.P. Parkman 1999. Integrated pest management of pest mole crickets with emphasis on the southeastern USA. Integrated Pest Management Reviews 4: 39-52.
Frank, J.H., J.P. Parkman and F.D. Bennett. 1995. Larra bicolor (Hymenoptera: Sphecidae), a biological control agent of Scapteriscus mole crickets (Orthoptera: Gryllotalpidae), established in northern Florida. Fla Entomologist 78: 619-623.
Dr. Jennifer L. Gillett
UF/IFAS Entomology and Nematology Dept.
Gainesville, FL 32611-
gillett@ifas.ufl.edu
352-392-1901 ext. 122
Dr. Howard J. Frank
UF/IFAS Entomology and Nematology Dept.
Gainesville, FL 32611-
frank@ifas.ufl.edu
352-392-1901 ext. 128
The following sheets explain the biology and importance of several biological control
organisms.
The most important insect pests of turf and pastures
in Florida are mole crickets. Their feeding and
tunneling also destroy seedlings of tomato and pepper.
S. scapterisci is specific to mole crickets. The
nematode was successfully introduced by inoculative
applications in golf courses and pastures in Florida.
The insecticidal nematode S. scapterisci is produced
and marketed as a biopesticide under the name
Nematac S®. When it is applied according to directions
as a biopesticide, it will kill a high percentage of pest
mole crickets within a few days. It will not harm other
insects, plants, animals or humans.
Description:
This nematode has a special advantage: it reproduces
inside pest mole crickets and its progeny are released
into the soil. The progeny can persist, generation after
generation, for years so long as a few pest mole crickets
remain. The progeny will spread, carried by infected
mole crickets. This means that the nematode can
provide years of suppression of pest mole cricket
populations. It is compatible with the use of most
chemical insecticides (for killing other kinds of pest
insects). It is not compatible with the use of chemical
nematicides.
Adapted by J.L. Gillett from EENY-92 Featured Creature by: K.B. Nguyen. Photograph by: Lyle Buss.
Mole Cricket Nematode
Steinernema scapterisci
Introduction
References: CONTACT INFORMATION:
Prepared by: Dr. Jennifer Gillett
Figure 1. Adult Geocoris uliginosis. Photograph by: Lyle Buss.
Figure 2. Nymphal Geocoris uliginosis. Photograph by: Lyle Buss.
Figure 3. Adult bigeyed bug, Geocoris sp. feeding on a whitefly nymph. Photograph by: Jack
Bigeyed Bug, Geocoris punctipes, uliginosis & bullatus
Biology and Lifecycle: Eggs are laid on plants. The biologies of the individual species of bigeyed bugs in Florida are somewhat similar. Females of Geocoris punctipes lay 75 to 150 eggs, depending on the quantity and quality insect prey. Eggs hatch in 6 to 10 days. Development of the nymphal instars requires almost 20 days, depending on temperature. The adults live over three weeks. Environmental Factors: Bigeyed bugs overwinter in northern Florida from November to March as mated females in reproductive diapause. A combination of day-length and temperature influences the onset and duration of reproductive diapause. A portion of the population remains active during the winter in Florida, even in the northern part of the state. Adult: Small oblong, elliptical bugs about 1/16 inch in length. Several features separate bigeyed bugs from similar bugs. The head is broader than long and the prominent eyes curve back- ward and overlap the front of the pronotum. The color of G. uliginosis is nearly all black except for a pale border along each side. The other species are pale above.
Immatures: The nymphal instars are oblong, elliptical. Late instars have wingpads. The color of the head and thorax of G. uliginosis late instar nymphs is dark brown. The color of the head and thorax of the nymphs of other species is pale.
Host Species: Abundant on crop and wild plant species.
Prepared by: Dr. Joe Funderburk
CONTACT INFORMATION:
Dr. Joe Funderburk UF/IFAS NFREC 155 Research Rd Quincy, FL 32351- jef@ufl.edu 850-875-
Mead, F.W. 2004. Big-eyed bugs Geocoris spp. (Insecta: Hemiptera:
Reitz, S.R., E.L. Yearby, J.E. Funderburk, J. Stavisky, M.T. Momol and S.M. Olson. 2003. Integrated management tactics for Frankliniella thrips (Thysanoptera: Thripidae) in field-grown pepper. Journal of Economic Entomology 96:1201-1214.
Coll, M. and J.R. Ruberson (editors). 1998. Predatory Heteroptera: Their Ecology and Use in Biological Control. Entomological Society of America, Lanham, Maryland.
Effectiveness: Integrated pest management programs are designed to conserve populations of predatory bugs and other natural enemies through the use of cultural tactics, pest resistant crop cultivars and reduced-risk insecticides. This predator feeds on aphids, mites, whiteflies, thrips and the eggs of numerous species of pests.
Habitat/Nutritional Requirements: These predatory bugs feed on plant juices without causing damage to the plants. These predators are generalists feeding on many small insects and insect eggs.
References:
Lygaeidae). UF/IFAS Pub. EENY-252.
Dykinga, USDA.
Prepared by: Dr. Joe Funderburk
Biology and Lifecycle: Individual eggs are laid in plant tissues. Females lay over 75 eggs when consuming adequate numbers of insect prey. Eggs hatch in 6 to 10 days. Development of the nymphal instars requires at least 10 days, depending on temperature. The adults live three to four weeks.
Environmental Factors: The species overwinters as mated females in reproductive diapause. They are active from March to November in northern Florida, and year-round in southern Florida. A combination of day-length and temperature influences the onset and duration of reproductive diapause.
Adult: Elliptical with a triangular head. The head and thorax are shiny and black. The forewing has a small dark area at the base of the first pair of legs, then a whitish yellow area, then a triangular dark area. The rest of the forewing is membranous and pale. Immatures: The five nymphal instars are ovoid. The first instar is slightly yellow. Later instars get progressively darker in color. The last instar is mahogany in color.
Host Species: Abundant on many crop and wild plant species. Very abundant on species of peppers (Capsicum spp.), but not on tomato (Lycopersicon esculentum).
Habitat/Nutritional Requirements: Minute pirate bugs have co-evolved with plants including pepper, okra, and cotton that have special structures called domatia that produce food and shelter for predators. The domatia allow predator populations to survive and successfully reproduce in the absence of prey. Minute pirate bugs persist in peppers after suppressing prey to low population levels, by feeding on pollen and plant juices without doing damage. Adults and nymphs are highly aggregated in the flowers of pepper. Effectiveness: Integrated pest management programs are designed to conserve minute pirate bug populations through the use of cultural tactics and reduced-risk insecticides. Minute pirate bugs provide control of thrips when there is at least one predator per 180 prey. The predator also feeds on aphids, mites, whiteflies, and the eggs of numerous species of pests.
BIOLOGICAL CONTOL:
Minute Pirate Bug, Orius insidiosus
Figure 1. Adult minute pirate bug. Photograph by: James Castner.
Figure 2. Nymphal minute pirate bug. Photograph by: Lyle Buss.
Figure 3. Adult Orius insidiosus preying on an adult thrips. Photograph by: Stuart Reitz.
CONTACT INFORMATION:
Dr. Joe Funderburk UF/IFAS NFREC 155 Research Rd Quincy, FL 32351- jef@ufl.edu 850-875-
Funderburk, J., S. Olson, J. Stavisky and Y. Avila. 2004. Managing thrips and tomato spotted wilt in pepper. UF/IFAS Pub. EENY-658.
Funderburk, J. and J. Stavisky. 2004. Biology and economic importance
Reitz, S. R., E.L. Yearby, J.E. Funderburk, J. Stavisky, M.T. Momol and S. M. Olson. 2003. Integrated management tactics for Frankliniella thrips (Thysanoptera: Thripidae) in field-grown pepper. Journal of Economic Entomology 96: 1201-1214.
References:
of flower thrips. UF/IFAS Pub. ENY682.
Stink Bug & Ladybird Beetle
The predatory stink bug is considered a beneficial
insect because most of its prey consists of plant-
damaging bugs, beetles, and caterpillars. It seldom
plays more than a minor role in the natural control of
insects in Florida, but its prey includes such economic
species as southern green stink bug. The females lay
egg masses with individual eggs that are somewhat
barrel shaped. Identification of the nymphs is difficult,
particularly the earlier instars. The young stink bugs
lack wings and have tubelike piercing-sucking
mouthparts. The adult male length is approximately
12 mm and can be distinguished from all other stink
bugs in the southeastern U.S. by a reddish spot at
each corner of the scutellum outlined against a blue-
black to purplish brown ground color. Variations occur
that might cause confusion with somewhat similar stink
bugs. E. floridanus has been collected during all
months of the year in Florida. There is a peak in the
spring and again in the fall.
There are many species of ladybirds. Ladybird adults
are oval, range in length from about 1 mm to over 10
mm depending upon species and have wings. Females
on average are larger than males. Adults of some
species are brightly colored. Larvae are mobile and in
some species are protected by waxy secretions. Pupae
are unprotected by a cocoon but larvae may wander
some distance from feeding sites before pupating.
Typically, ladybirds have several generations each year
and reproduction is slowed or halted by cooler winter
weather, when adults may hibernate. Predatory species
feed on mites, whiteflies, cottonycushion scale,
mealybugs, armored scale insects, scale insects and
aphids. Most species of ladybirds are considered
beneficial because they are predators of Homoptera
or Acarina, many of which are considered to be pests.
These predatory ladybirds contribute to the regulation
of populations of their prey, and in some situations
contribute a high level of regulation.
Description:
Description:
Florida predatory stink bug
Euthyrhynchus floridanus
Ladybird beetles
Coleoptera: Coccinellidae
Adapted by J.L. Gillett from EENY-157 Featured Creature by: F. Mead. Photographs by: Lyle Buss.
Adapted by J.L. Gillett from EENY-170J Featured Creature by: H. Frank and R.F. Mizell, III. Photographs by: Russ Mizell and Lyle Buss.
Prepared by: Dr. Jennifer Gillett
Wasp Parasitoid & Predatory Mite
Several species of parasitoid wasps occur naturally in
the United States, some species are sold for release
in augmentative biological control programs. They are
considered biological control agents of noctuid pests
of vegetable crops, such as armyworm, hornworm,
cabbage looper, etc. Insects infected with larvae of
wasp parasitoids may look like other larvae or they
may have a sluggish nature. When wasp larvae
emerge from the host, they immediately begin spinning
a tight silky cocoon. The cocoon is usually white. The
cocoon can remain attached to the host larvae or it
will be attached to plant material near the host. In
Florida, many parasitoids naturally are abundant
throughout the summer, but populations tend to decline
from October to April.
The predatory mite N. californicus prefers spider mites
(Tetranychidae) as food, but will also consume other
mite species, small insects, such as thrips, and even
pollen when the primary prey is unavailable. N.
californicus is often used to control the twospotted
spider mite, Tetranychus urticae, and other
phytophagous mites on various crops in temperate and
subtropical regions around the world. Natural
populations of N. californicus are found in Florida.They
prefer warm 10 - 33°C (50 - 91°F) temperatures, but
they can tolerate much colder temperatures for short
periods of time. For example, they can survive the
winters in north Florida where temperatures can fall
below freezing at night. They can tolerate a wide range
of humidity (40 - 80% relative humidity), but prefer
humidity at the upper end of this range. High quality
N. californicus are commercially available for
augmentative biological control.
Description:
Wasp Parasitoid
Adapted by J.L. Gillett from EENY-123 Featured Creature by: A. Sourakov and E. Mitchell. Photographs by: Debbie Waters and Andrei Sourakov.
Predatory mite
Neoseiulus californicus
Adapted by J.L. Gillett from EENY-359 Featured Creature by: E.M. Rhodes and O.E. Liburd. Photograph by: Lyle Buss.
Description:
Prepared by: Dr. Jennifer Gillett
Beneficial Agents Interaction with Pesticides
Prepared by: Dr. Mark Mossler
Table 1. Toxicity of chemical pest management tools to beneficial invertibrates in FL tomato and pepper.
