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Part B 

IPM Treatment Protocols

Claire Cooney, 1999

McGill University Phytotron 

 

 

The McGill University Phytotron practices IPM (integrated pest management) in its pest management program. IPM is an established system whereby a combination of cultural, physical, mechanical, biological and chemical techniques are employed to effectively combat pest infestations. The following protocols have been developed from experience with pests encountered within the Phytotron and consultation with other phytotrons, university plant research growth facilities and IPM specialists.  All protocols rely upon sanitation, plant health, monitoring and treatment as a basis of effective control. See Part A - Responsibilities of Research Users and Phytotron Staff for detailed descriptions of these areas.

THRIP

Biology
Thrips are tiny winged insects between 1- 4 mm in length that are amongst the most troublesome pests within a greenhouse. Species commonly encountered include Thrips tabaci (onion thrips), Heliothrips haemorrhoidalis (greenhouse thrips), Hercinothrips femoralis (banded greenhouse thrips) and Frankliniella occidentalis (western flower thrips). The latter only appeared in North America within the last 15 years and has become a serious pest because of its resistance to most pesticides.

Western flower thrips (WFT), Frankliniella occidentalis, are tiny insects about 1mm long that feed on flower and leaf tissues by biting into cells and sucking out the contents. When the cells die, conspicuous silver scarring is seen often with small black dots that are excreta. Young thrips larvae frequently feed within developing flower buds and stem tips resulting in severe deformation of flowers and foliage. WFT carry many viruses including tomato spotted wilt virus (a broad spectrum virus attacking many plants). Plants that become infected with viruses must be destroyed. The mature thrips has two pairs of fringed wings and varies in color from yellow, orange tan, reddish brown to black.

Thrips are capable of both sexual and asexual reproduction, a feat that adds to the difficulty in controlling them. During asexual reproduction an adult female undergoes facultative parthenogenesis producing only male offspring (Brodsgaard, 1989; Immaraju et al, 1992). During sexual reproduction mainly female offspring are produced. Adult females make a small hole within plant tissue with their saw-like ovipositor and deposit their eggs. The eggs develop within the tissue forming larvae. The larvae emerge from the leaf tissue, feed for 8-10 days and undergo three more changes in development before pupating. Depending upon the species the pupa either remains on the leaf or falls to the ground. Within 7 to 10 days an adult appears and flies to the upper portion of the plant to feed and lay eggs repeating the cycle.

Cultural Controls
Start from clean seed. Follow proper watering and fertilizing regimes to maximize plant health. Eliminate any weeds in or near greenhouse.

Physical Controls
Monitor adult populations with yellow sticky traps. Exclude thrips from growing areas through isolation and screening. Remove infected plant parts that may be harboring eggs. Dispose of plant residues immediately.

Biological Controls
Successful control can be achieved using IPM with a combination of biological control agents in the form of parasitoids and predators that target each point in the thrips' life cycle (Gillespie, 1989; Gillespie and Quiring. 1990; Hoy and Glenister, 1991; Greene and Parrella, 1992; Elliott, 1993, 1998, Malais and Ravensberg, 1992).

Predators include the minute pirate bug (Orius insidiosus), a voracious predator that attacks larval and adult thrips, Hypoaspis miles and Amblyseius cucumeris. The latter are predatory mites. H. miles is a small brown soil dwelling mite that attacks thrips pupae while A. cucumeris dwells in the plant canopy, preying upon newly emerging larvae.

Parasitoids include the nematode Steinernema carpocapsae and the tiny wasp Thripobius semiluteus. Steinernema applied to the soil is a good prophylactic measure for species pupating in the soil. The nematode attacks thrips pupae by entering the body through natural openings. Once inside, the nematode releases a bacterium (Xenorhabdus spp.) that paralyzes and kills the thrips within 24 to 48 hours. T. semiluteus oviposits its egg within the larva of greenhouse thrips (Heliothrips haemorrhoidalis). The parasitoid feeds off the body contents of its host, eventually killing it.

Chemical Controls
It has been demonstrated that thrips are highly resistant to pesticides (Robb, Parrella and Newman, 1981; Nasruddin and Smitley. 1991; Immaraju et al, 1992; Zhao, Liu and Knowles 1993,1995; Robb, Newman, Virzi and Parrella 1995), and the use of chemical control alone is ineffective. The use of compatible nonresidual chemicals such as insecticidal soap and horticultural oil may be used to reduce thrips populations before introduction of biocontrols and/or spray hotspots during flare-ups.

Keys to success:

bullet Identify the species of thrips and select the corresponding biological control agents.
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Introduce the biological control agents at the first sign of thrips when the population is low.
bullet Adjust temperature and humidity to favour the biocontrol.
bullet Monitor pest and beneficial populations
bullet Knock back thrips population with compatible pesticides if necessary.

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APHIDS

Biology
Green peach aphids (Myzus persicae) are small (3mm or less) soft-bodied insects that feed on plants by piercing plant tissue and sucking out the sap. Tissue may become deformed after infestation due to hormonal imbalance by the aphids and their secretion of a sugary substance (honeydew) that becomes black with fungal growth. Winged aphids may transmit viruses.

In greenhouses, asexual reproduction is commonly encountered. Adult females become parthenogenic and give birth to live young that are genetic clones. These in turn give birth to more live young in as little as 7-10 days. In certain instances each individual can produce between 40 to 100 offspring. Within a few days under optimal conditions, an aphid colony can become established. When the aphid colony becomes too populated, winged females develop that migrate to other plants and areas. Sexual reproduction sometimes occurs during the autumn. Male and female forms appear and mate. Eggs are produced that over winter and develop into nymphs in the spring.

Cultural Controls
Follow proper watering and fertilizing regimes to maximize plant health. Do not over fertilize as plant tissue with high nitrogen content attracts aphids. Use banker plants to build beneficial populations in situ (Bennison and Corless, 1993; Dr. Les Shipp, Agriculture Canada - Harrow -personal communication).

Physical Controls
Screen as much as possible to exclude aphids from growing areas. Set up yellow sticky traps to detect and catch winged flying aphids. Inspect leaves and stem tips for crawling aphids. Spray infested plants with a stiff stream of water to dislodge aphids.

Chemical Controls
Plants may be sprayed with insecticidal soap (Miller and Uetz, 1998) or Enstar to reduce aphid populations before the introduction of biological agents or at later stages of infection if populations of aphids boom. Instances of reproductive stimulation resulting in flare-ups following pesticide (carbamate, pyrethroid, organophosphate) application have been documented in the literature (Grafton-Cardwell, 1991; Lowery and Sears, 1986; Rongai and Cerato,1996). This in turn may lead to the development and entrenchment of resistant pest populations ( Devonshire, 1989 a, b; O'Brien and Graves, 1992; Moores, Devine and Devonshire, 1994; Blackman, Spence and Field 1996; Deguine, 1996; Foster, Harrington and Devonshire 1996) and is not recommended.

Biological Controls
Aphids can be effectively controlled using combinations of beneficial parasites and predators (Gilkeson and Klein, 1981; Steiner and Elliott, 1987; Elliott, 1993, 1998, Malais and Ravensberg, 1992). Early introduction of biocontrols and frequent monitoring is crucial to successful control. When biocontrols are released, yellow traps should be removed to prevent beneficials from becoming trapped.

The aphid midge, Aphidoletes aphidimyza, is a predator whose larvae attack and paralyze their victums before feeding on digested body contents. Adult midges are active at night and feed on the honeydew left by the aphids. Aphidoletes enters diapause (a type of dormancy) with cooler temperatures and shortened days. Supplemental lighting should be used in autumn or winter months.

Aphidius matricariae is a small Braconid wasp that parasitizes green peach aphids and closely related species. The female wasp deposits her eggs through an ovipositor into the abdomen of the aphid. As the egg develops the aphid swells and changes color becoming more reddish. Continued growth of the larva results in the death of the aphid. At this point the aphid body forms a golden leathery pupal casing called a mummy. Adult parasites exit the mummy by chewing a round hole through the dorsal wall and seek new hosts. Aphidius colemani is another parasitoid that can be incorporated to control Aphis gossyppii.

Ladybugs (Hippodamia convergens) are predators that feed on slow moving soft-bodied insects. They are extremely useful for outbreaks of melon aphid (Aphis gossypii). Both the larva and adult are avid feeders; larvae consume up to 400 aphids each while adults eat an astonishing 5,000.

Keys to success:

bullet Identify the species of aphid and select the corresponding biological control agents.
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Adjust temperature, humidity and lighting to favour the biocontrol.
bullet Low pest population
bullet Monitor pest and beneficial populations
bullet Knock back with insecticidal soap or Enstar if pest population booms

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SPIDER MITES

Biology
Two spotted spider mites (Tetranychus urticae) are common greenhouse pests that often appear during hot dry conditions. Adults are minute, oval shaped, lightly colored mites with two dark spots on their backs. Spider mites bite into the leaf tissue and suck out the cellular contents resulting in a needle like speckled appearance. At high densities, plants are covered in webs and if left untreated will die.

Reproduction can be either sexual or parthenogenic with only males produced. Adult females lay eggs on the undersides of leaves in a webbing. Nymphs emerge and resemble adults in form. Five stages of development occur from egg to adult and all stages feed on plants. The length of the life cycle is greatly dependent on temperature. At 21°C it is 14 days. At 30°C adult females can lay 100 eggs within 1 week and live for 30 days, producing theoretically 13,000,000 offspring.

Cultural Controls
Increasing relative humidity by frequent misting and/ or spraying plants with water not only decreases spider mite reproductive rate but also dislodges mites from plants. Decreasing temperatures to 23°C or lower reduces reproductive rate and population growth.

Physical Controls
Prune away affected plant parts, remove weeds from within the greenhouse and outside surrounding areas. Isolate infected plants.

Biological Controls
Several different species of predatory mites are used in the control of the two spotted spider mite (Steiner and Elliott, 1987; Elliott, 1993, 1998, Malais and Ravensberg, 1992). Phytoseiulus persimilis has been successfully used in the management of two spotted spider mite since the sixties. Adults are about 0.5 mm long and are bright reddish orange colored. Under optimal temperatures (23°C - 25°C) and humidity (70 - 80%RH) P. persimilis reproduces faster than its prey, eating all developmental stages (egg, nymph and adult). Its life cycle is the same as that of the two spotted spider mite.

Other species of predatory mites can withstand humidities and temperatures outside the range favored by P. persimilis. For example, when humidity is low and temperatures are high, Mesoseiulus longipes is useful or Galendromus occidentalis. When temperatures and pest population levels are lower, Neoseiulus fallacis can survive even in the absence of prey, feeding on pollen. Neoseiulus californicus survives even longer than N. fallacis in the absence of prey but is not as aggressive as P.persimilis or M. longipes.

Another biocontrol is the tiny midge, Feltiella acarisuga, whose larvae are predatory. The tiny beige maggots eat for about a week before pupating and repeating the cycle. Feltiella populations increase in proportion to prey increase and compliment P. persimilis. (Mahr, 1998).

The beetle, Stethorus punctillus, is an aggressive predator of spider mites. It is native to North America and is capable of reducing pest populations quickly. Both adult and larvae prey on the spider mite consuming between 75-100 mites (Hull, 1995).

Chemical Controls
Chemical control alone will not result in successful pest control because of increased mite fecundity following pesticide application (Brandenburg and Kennedy, 1987; Jones, 1990; Shanks,Antonelli and Congdon 1992). Judicious use of chemical control in combination with the above, however, can manage pest populations. High pest populations can be reduced by spraying infected plants with insecticidal soap or horticultural oil (Miller and Uetz, 1998) followed by the introduction of biological controls.

Keys to success:

bullet Identify the species of mite and select the corresponding biological control agents.
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Increase relative humidity, decrease temperature
bullet Introduce predators when mite population is low
bullet Monitor pest and beneficial populations

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FUNGUS GNATS AND SHORE FLIES

Biology
Fungus gnats (Bradysia impatiens) are small (2 - 5 mm long) black flies found on wet soil. They are distinguished from shore flies by their long segmented antennae, long legs and a prominent Y-shaped vein on their wings. Their larvae are thin white threadlike maggots with black heads and are found in the soil. They feed on decaying organic matter, roots and the bases of young plants and cuttings. Damage can be considerable for young plants and diseases from fungal, bacterial or viral pathogens can be spread.

Females can lay up to 200 eggs that hatch into larvae within 4 - 6 days. Maggots remain active for approximately two weeks and then pupate in the soil 4-6 days at which time the adult emerges.

Shore flies (Scatella stagnalis) are strong flyers in contrast to fungus gnats. They are larger, have short antennae, red eyes and dark wings with five clear spots. Their larvae are up to 6 mm in length and are yellowish brown in color with no identifiable head. The life cycle is similar to that of the fungus gnat. Both adults and larvae eat algae on the soil surface and surrounding areas. Although they do not damage plants directly, they can be vectors for soil pathogens. Control is dependent on reduction of wetness and subsequent elimination of algae.

Cultural Controls
The first step in cultural control should be to reduce organic matter. This can be accomplished by reducing the amount of peat or humus in the soil mixture and removing all decaying leaves and other plant parts from the soil surface of the pot and underneath benches. The next step should be to reduce wetness by improving soil drainage and watering only when the soil surface is dry. Fans should be installed to improve ventilation.

Physical Controls
Physical techniques such as covering the soil surface with light colored sand act as a repellent and barrier preventing adults from mating (Doug Walker, UC Davis, personal communication). Yellow sticky traps can help reduce population numbers by catching flying adults.

Biological Controls
Biological control agents include Hypoaspis miles, Steinernema species and Bacillus thuringiensis. Hypoaspis is a soil dwelling mite that attacks fungus gnat larvae. It is small (less than 1mm in length) and light brown in color. Reproduction is sexual with eggs hatching within 2 - 3 days. The mite eats 1 - 5 larvae per day. Control is best when Hypoaspis is introduced prior to fungus gnat population establishment (Gillespie and Quiring,1990).

Steinernema carpocapsa and Steinernema feltiae are two nematode species that parasitize fungus gnat larvae. They are applied directly to the soil through irrigation. Reproduction is sexual with third stage larvae infecting the fungus gnat larvae. The nematode enters the host larva through openings in its body cavity and releases bacteria that digest it. The available food products are then metabolized by the nematodes that subsequently reproduce and seek out new prey.

Bacillus thuringiensi (B.t.) is bacterium that is applied to the soil through irrigation. Different strains of the bacterium affect a variety of different insects. Insects eat the bacterium that then releases toxic cystaline proteins in their guts. As the intestinal lining is paralyzed, the insect stops eating, becomes less active and eventually dies from starvation and tissue damage.

Chemical Controls
Adult populations can be reduced by spraying with insecticidal soap.

Keys to success:

bullet Reduce soil moisture
bullet Reduce organic content in soil mix
bullet Apply Hypoaspis and nematodes or B.t. at planting
bullet Monitor pest and beneficial populations  

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WHITEFLY

Biology
Throughout North America, there are three species of whitefly that are major greenhouse pests. They include, greenhouse whitefly, Trialeurodes vaporariorum, Sweet Potato Whitefly, Bemisia tabaci, and silverleaf whitefly, Bemisia argentifolii, that until recently was also known as the "B" strain of sweet potato whitefly (Flint and Parrella, 1995). The latter two species have become resistant to most pesticides and have caused severe damage to both field and greenhouse crops.

The adult greenhouse whitefly, Trialeurodes vaporariorum, is approximately 1 mm in length with an average lifespan of 20 to 30 days. It has a yellow body with white wings that lay in a flat plane against its body. Whitefly females lay between 200-400 eggs on the undersides of leaves. Each egg is attached on a small stalk. The eggs hatch within 2 to 8 days forming oval larvae that resemble scales. These in turn molt during three more instar stages. In the final stage of metamorphosis, the pupa is formed from which the adult emerges after about 5 days. Both adults and young feed by inserting a stylus into the phloem and sucking sap, damaging tissues. A sticky substance, "honeydew" is secreted that secondarily becomes infected with a black mold. Infected plants show symptoms of yellowing, wilting and stunted growth. If not caught in time, entire plantings may be decimated.

In practice, it is difficult to differentiate between B. argentifolii and B. tabaci. By examining pupae, one can however, distinguish between T. vaporariorum and Bemisia spp. The pupa of T. vaporariorum is oval shaped and has a ring of wax filaments around the edge of its body. The pupa of Bemisia is pointed at one end and has no wax filaments. In side view, the Bemisia pupa looks like a squished football; the edges are tapered. The pupa of T. vaporariorum in side view resembles a hockey puck; there is a cylindrical "wall" between the parallel upper and lower surfaces. It is important to identify which species of whitefly is present to ensure successful control.

Physical Controls
Hang yellow sticky traps amongst plants to detect the first sign of pest outbreak and to monitor subsequent population level. Shake plants to disturb resting whiteflies. Gently vacuum dispersing adults.

Cultural Controls
Examine each new plant that enters the greenhouse and quarantine if possible.

Biological Controls
Greenhouse whitefly can be successfully controlled using Encarsia formosa, a small parasitic wasp (Van Lenteren, Van Roermund and Sutterlin, 1996). The female wasp preferentially deposits its eggs into whitefly larvae in the third and fourth instar phases. Infected scales appear black and are easily distinguished. The parasitic grub grows within the whitefly scale undergoing three larval phases and a pupal stage. As it grows and metamorphoses, it consumes the whitefly larva. After about 10-11 days, the adult Encarsia emerges through an exit hole. The adult female is about 1/2 mm long with a yellow abdomen. Males are all black and slightly larger. Adults preferentially feed on second stage whitefly larvae .

Eretmocerus californicu is a tiny yellow wasp that parasitizes Bemisia spp. Its mode of action is similar to that of Encarsia. Parasitized scales are yellowish in color.

Delphastus pusillus is a predatory beetle that attacks all three species of whitefly.

Chemical Controls
While waiting for the Encarsia to arrive, spray affected plants with a 2% solution of Safer's Soap or Enstar 2. This will keep pest populations from booming until the parasite arrives. After the parasite has been released stop using the soap to prevent killing the parasite.

Keys to success:

bullet Identify which species of whitefly is present
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Introduce the correct biological control when pest populations are low
bullet Adjust temperature, humidity and lighting to favour the biocontrol
bullet Monitor pest and beneficial populations
bullet Knock back with Enstar or insecticidal soap if necessary

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MEALYBUGS

Biology
In the citrus mealybug, Planococcus citri, males are rarely seen. Females are oval shaped, about 3-4 mm in length and 2-3 mm wide. Their body is pinkish with a white waxy covering and they are mostly immobile. Males are smaller than females and have two pairs of wings on their back. Their sole purpose is to fertilize the female and they do not feed. Female nymph and adults feed on all plant parts, sucking sap that stunts or deforms growth. Leaves, flowers and fruit may abort. Honeydew is secreted that subsequently becomes infected with black sooty mold.Longtailed mealybug, Pseudococcus longispinus, differs from citrus mealybug by the presence of long filaments at the end of its body.

Physical Controls
Hose off plants with a stiff stream of water to remove insects. Alternatively, pruned affected parts.

Cultural Controls
Examine each new plant that enters the greenhouse and quarantine if possible.

Biological Controls
Cryptolaemus montrouzieri is a predatory beetle native to Australia that is effective against a variety of mealybugs. All stages of development, larval and adult actively seek out and kill their prey. Adults are about 4 mm in length, black with an orange head. Larvae are similar to mealybugs in their white color and waxy appearance but are distinctive in their "alligator" like shape. Cryptolaemus is extremely effective against large populations of mealybugs. Females lay their eggs within a white fluffy mass. These hatch into nymphs that undergo three stages of development. Only the males experience complete metamorphosis.

Leptomastix dactylopi is a parasitic wasp of citrus mealybug, Planococcus citri. Adults are yellowish brown in color, about 3 mm in length. Females lay their eggs within third stage larvae of the mealybug. Larvae develop within the mummy and completely devour their host. After pupation, the new wasp cuts an exit hole and emerges, feeding on honeydew. Adults are strong flyers and can search out prey in low numbers making them excellent control agents for low density populations. Other parasitic wasps include: Anagyrus fusciventris and Pseudoaphycus angelicus for longtailed mealybug and Leptomastidea abnormis for citrus mealybug.

Chemical Controls
Spray with Insecticidal soap or Enstar 2.

Keys to success:

bullet Identify the species of mealybug and select the corresponding biological control agents.
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Hose off plants
bullet Introduction of biocontrols at low pest population level
bullet Adjust temperature, humidity and lighting to favour the biocontrol.
bullet Monitor pest and beneficial populations

 
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SCALE

Biology
Scales are divided into two groups, the armored and the soft shell.
Armored scales secrete a shell of wax and cast skins that protects the underlying soft body and may be removed. The armored scales have large mouth parts that invade mesophyll enabling them to suck out rich cell contents. The food obtained is used so efficiently that no honeydew is produced. Examples of scales of this type are oystershell scale (Lepidosaphes beckii) , California red scale (Aonidiella aurantii), and San Jose scale (Aspidiotus perniciosus).

Soft shelled scales have no covering shell even though their skin becomes sclerotized with age. It cannot be removed without killing the insect. Soft shelled scales feed from phloem and produce copious amounts of honeydew that subsequently becomes infected with black sooty mold. Examples of this type of scale include, brown soft scale (Coccus hesperidum), hemispherical scale (Saissetia coffeae) and black scale (Saissetia oleae).

The female brown soft scale (Coccus hesperidum) keeps its eggs within its body till giving birth to live crawlers. The young mobile crawlers are yellowish with a mottled rounded shell. They begin to feed immediately after birth and molt twice. Older second stage nymphs are sessile. Males are rare and undergo four stages of metamorphosis before emerging as winged adults.

Adult female California red scale (Aonidiella aurantii) have a round cover underneath which they lay 100 -150 eggs during their life time. Newly hatched crawlers are mobile for only a short period before settling and molting to the adult sessile form. Within the second instar differences are seen between male and female nymphs. Males develop an elongated form, while female continue in a circular pattern. Adult males are winged and live for only 6 hours during which time they mate.

Cultural Controls
Avoid over fertilization of plants.

Physical Controls
Quarantine and inspect all new plants for infestation. Physically remove scales from plants with brush and alcohol. Hose down plants to remove crawlers and wash off honeydew.

Biological Controls
Metaphycus helvolus is a small parasitic wasp about 2mm in length that is black and yellow in color. It is effective for brown soft scale or hemispherical scale. The female lays eggs under crawlers and second stage nymphs. The parasitic grubs feed on the scales and develop into adults within two weeks. Adult wasps also feed on non-parasitized scales, killing them.

Aphytis melinus is a parasitic wasp of California red scale and oleander scale. The adult female lays her eggs within host scales. Larvae develop within the mummy destroying the host before exiting. One Aphytis can kill 30 scales. Adults live for 26 days and feed on honeydew.

Lindorus lophanthae, Chilocorus nigritus and Harmonia axyridis are predatory beetles that feed on both armored and soft shelled scale. Adults and larvae of both are voracious feeders.

Chemical Controls
Spray infected areas with horticultural oil or Enstar 2. This is only effective for mobile stages.

Keys to success:

bullet Identify the species of scale and select the corresponding biological control agents.
bullet Review spray record and make sure that no toxic residual pesticides have been used (check the list supplied by the IOBC).
bullet Removal of honeydew
bullet Hosing off plants; pruning
bullet Introduction of biocontrols at low pest population level
bullet Adjust temperature, humidity and lighting to favour the biocontrol.
bullet Monitor pest and beneficial populations

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Complexities of the System

The above protocols address individual pests. What happens when there is more than one pest present? The more pests present, the more complex the system becomes, the more balancing is required. The use of a chemical when two or more pests are present has to be carefully decided. When choosing a pesticide to knock back a pest population increase, look at what effect it has on the biocontrol agents present. For example, if green peach aphids and western flower thrips are both present, and the aphid population booms, spraying with Pirliss (an aphicide) would not be a good choice. It will kill the biocontrols of the aphids (Aphidius and Aphidoletes) and one of those of the thrips (Orius). The residue left will prevent their reintroduction for one to two weeks. In that time period, the aphid population may or may not increase depending upon resistance but the Thrips population will definitely increase. The biocontrol agent that targeted the adult phase of the life cycle will be gone and although Pirliss is not lethal to the other thrips controls (A. cucumeris and H. miles) some mortality will occur resulting in decreased predation. Two pesticides that could be used to knock back the aphid population and not leave lethal residues would be insecticidal soap or Enstar. The soap would have an immediate effect on the aphids and also their controls to some extent (Aphidius that are in the mummy stage would be protected but adults would be killed as would all stages of Aphidoletes). The Enstar would not affect either biocontrol but would have a slower effect on the aphid population because it is an insect growth regulator; it prevents maturation.



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Literature Citations

Bennison, J. A. and S. Corless. 1993. Biological Control of Aphids on Cucumbers: Further Development of Open Rearing Units or "Banker Plants" to Aid Establishment of Natural Enemies. IOBC/WPRS Bull. 16(2): 5-8.

Blackman, R. L., J. M. Spence and L.M. Field. 1996. Inheritance of the Amplified Esterase Genes Responsible for Insecticide Resistance in Myzus persicae (Homoptera: Aphididae). Heredity 77:154-167.

Brandenburg, R. L. and G. G. Kennedy. 1987. Ecological and Agricultural Considerations in The Management of Twospotted Spider Mite (Tetranychus urticae Koch). Agricultural Zoology Reviews 2: 185-236.

Brodsgaard, H.F. 1989. Cited in Tommasini, M.and S. Maini 1995. Frankliniella occidentalis and Other Thrips Harmful to Vegetable and Ornamental Crops in Europe. In: Biological Control of Thrips Pests. 1995. Loomans et al (Eds) Wageningen Agricultural University Papers. pp vii- 42.

Deguine, J-P.1996. The Evolution of Insecticide Resistance in Aphis gossypii Glover (Hemiptera: Aphidiae) in Cameroon. Resistant Pest Management. Vol. 8, No. 1 Summer 1996. http://www.msstate.edu/Entomology/v8n1/rpmv8n1.html

Devonshire, A. L. 1989a. Insecticide Resistance in Myzus persicae: From Field to Gene and Back Again. Pesticide Sci. 26:375-382.

Devonshire, A.L. 1989b. Resistance of Aphids to Insecticides. In A.K. Aphids: Their Biology, Natural Enemies and Control. Volume 2C, Minks & P. Harrewijn (ed.). Elsevier, Amsterdam.

Elliott, D. 1993. Biological Technical Manual. Applied Bionomics.Sidney, B.C.

Elliott, D. 1998. Biological Pest Control in Controlled Environments. AERGC Greenhouse Newsletter 11(3): 1-7.

Flint, M.L. and M. P. Parrella. 1995. Pest Notes: Whiteflies in the Greenhouse
UC DANR Publication 2. IPM Education and Publications, University of California Statewide IPM. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn002.html

Foster, S. P., R. Harrington and A.L. Devonshire. 1996. Comparative Survival of Insecticide-susceptible and Resistant Peach-Potato Aphids , Myzus persicae (Sulzer) (Hemiptera: Aphididae), in low temperature field trials. Bull. Entomol. Res. 86: 17-27.

Gillespie, D. R. 1989. Biological Control of Thrips [Thysanoptera: Thripidae] on Greenhouse Cucumber by Amblyseius cucumeris. Entomophaga 34(2):185-192.

Gillespie, D. R and D. M.J. Quiring. 1990. Biological Control of Fungus Gnats, Bradysia spp. (Diptera: Sciaridae) and Western Flower Thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) in Greenhouses Using a Soil-Dwelling Predatory Mite, Geolaelaps sp. Nr. Aculeifer (Canestrini) (Acari: Laelapidae).Canadian Entomologist 122:975-983.

Grafton-Cardwell, E. E. 1991. Geographical and Temporal Variation in Response to Insecticides in Various Life Stages of Aphis gossypii (Homoptera: Aphididae) Infesting Cotton in California. J. Econ. Entomol. 84(3):741-749.

Greene, I. and M. Parrella. 1992. The Basics of Biocontrol. Greenhouse Grower (Dec): 69-72.

Hoy, C.W. and C.S. Glenister. 1991. Releasing Amblyseius spp. [Acarina: Phytoseiidae] to Control Thrips tabaci [Thysanoptera: Thripidae] on cabbage. Entomophaga 36 (4): 561-573.

Hull, L. 1995. Know Your Friends. Spider Mite Destroyer. Midwest Biocontrol News. 12(2) December. http://www.wisc.edu/entomology/mbcn/kyf212.html

Immaraju, J. A.; T. D, Paine; J. A. Bethke; K. L. Robb and J.P. Newman . 1992. Western Flower Thrips (Thysanoptera: Thripidae) Resistance to Insecticides in Coastal California Greenhouses. J. Econ. Entomol. 85(1):9-14.

Jones, V. P. 1990. Does Pesticide-Induced Activity of Twospotted Spider Mite (Acari: Tetranychidae) Really Contribute to Population Increases in Orchards? J. Econ. Entomol. 83(5): 1847-1852.

Gilkeson, L. and M. Klein. 1981. A Guide to the Biological Control of Greenhouse Aphids. The Ark Project. Charlottetown, P.E.I., Canada.

Lowery, D.T. and M.K. Sears. 1986. Stimulation of Reproduction of the Green Peach Aphid (Homoptera: Aphididae) by Azinphosmethyl Applied to Potatoes. J. Econ.Entomol. 79: 1530-1533.

Mahr, S. 1998. Know Your Friends, Feltiella acarisuga, Predator of Spider Mites. Midwest Biocontrol News. November V (11). http://www.wisc.edu/entomology/mbcn/kyf511.html

Malais, M. and W.J. Ravensberg. 1992. Knowing and Recognizing. The Biology of Glasshouse Pests and their Natural Enemies. Koppert B.V., Berkle en Rodenrijs, The Netherlands.

Miller, F. and S. Uetz. 1998. Evaluating Biorational Pesticides for Controlling Arthropod Pests and Their Phytotoxic Effects on Greenhouse Crops. HortTechnology 8(2):185-192.

Moores, G. D., G. J. Devine and A. L. Devonshire. 1994. Insecticide-insensitive Acetylccholinesterase Can Enhance Esterase-based Resistance in Myzus persicae and Myzus nicotianae. Pesticide Biochem. & Physiol. 49:114-120.

Nasruddin, A. and D. R. Smitley. 1991. Relationship of Frankliniella occidentalis (Tysanoptera: Thripidae) population density and feeding injury to the frequency of insecticide applications to gloxinia. J. Econ. Entomol 84(6):1812-1817.

O'Brien, P.J. and J.B. Graves. 1992. Insecticide Resistance and Reproductive Biology of Aphis gossypii Glover. Southwestern Entomologist 17: 115-122.

Robb, K.L., Parrella, M.P. and J. P. Newman. 1988. The Biology and Control of the Western Flower Thrips. Part 1. Ohio Florist's Association Bulletin 699:2-5.

Robb, K.L., J. Newman, J.K. Virzi and M.P. Parrella. 1995. Insecticide Resistance in Western Flower Thrips. NATO ASI Ser., Ser A, Life Sci. 276: 341-346.

Rongai, D. and C. Cerato. 1996. Insecticide-Stimulated Reproduction of Cotton Aphid, Aphis gossypii Glover, Resistant to Pirimicarb. Resistant Pest Management. Vol. 8, No. 2. http://www.msstate.edu/Entomology/v8n2/rpmv8n2.html

Shanks, C. H. Jr. A. L. Antonelli and B.D. Congdon. 1992. Effect of Pesticides on Twospotted Spider Mite (Acari: Tetranychidae ) Populations on Red Raspberries in Western Washington. Agriculture, Ecosystems and Environment, 38(1992) 159-165. Elsevier Science Publishers B.V.

Steiner, M. Y. and D. P. Elliott. 1987. Biological Pest Management for Interior Plant Scapes. 2ndEd. Vegreville, AB. Alberta Environmental Centre. 32p. AECV87-E1.

Van Lenteren, J. C. , H. J. W. Van Roermund and S. Sutterlin. 1996. Biological Control of Greenhouse Whitefly (Trialeurodes vaporariorum) with the Parasitoid Encarsia formosa : How Does it Work? Biological Control 6:1-10.

Zhao, G.; W. Liu and C. O. Knowles.1993. Diazinon Resistance Mechanisms in Western Flower Thrips. Resistant Pest Management. Vol. 5, No. 2 - Winter 1993. http://www.msstate.edu/Entomology/v5n2/fall93.html#art8.

Zhao, G.G., W.Liu and C.O. Knowles. 1995. Fenvalerate resistance mechanisms in Western Flower Thrips. (Thysanoptera: Thripidae). J. Econ. Entomol. 88(3): 531-535.



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Useful IPM  Links

http://www.nysaes.cornell.edu/ent/biocontrol/ (Cornell University)

http://www.biocontrol.ucr.edu/ (University of California at Riverside)

http://www.cips.msu.edu/biocontrol/ (Michigan State University)

http://www.biocontrol.ucr.edu/WFT.html (Thrips management)

http://ipmwww.ncsu.edu/biocontrol/biocontrol.html (North Carolina State University)

 

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Copyright October 1999  Revised January 2003  
[Claire Cooney, McGill University Phytotron]. All rights reserved.

Last update: Sept. 30, 2009