Dr. Vera Krischik's Insecticide Section (Weeks 6-8, Feb. 21 to Mar. 7)

Lecture Syllabus 2007

Feb 21, 23, 2007: Readings for lecture

1. Ware, G. W. 2000. The pesticide book. 5th edition, Thomson Publications, Chapter 4: Insecticides.

2. Ware, G. W. 2000. The pesticide book. 5th edition, Thomson Publications, Chapter 24: Biorationals.

3. Krischik, V. 2004. List of insecticides by class: http://www.entomology.umn.edu/cues/Krischikinsecticides06.doc

4. Cranshaw, W. 2004. Relative hazards of turf and ornamental pesticides to non-target species. In Krischik, V. ed, IPM of Midwest Landscapes. 315 pp: http://www.entomology.umn.edu/cues/Web/045RelativeHazzards.pdf

5. Read and understand Table 1 and 2 below.

Table 1 and 2 will be discussed in class on Feb 21 and Feb 23

Table 1: Key to sites:  C =Christmas tree, G = greenhouse, I = interiorscape, L = landscape, N = nursery, T = turf, S =shade house

Table 2: Insecticide label warnings and rationale

Feb 23, 2007: Lecture:

Pesticide labels are available at:

1. CDMS: Label searches: http://www.cdms.net/manuf/default.asp

2. CP Greenbook: http://www.greenbook.net/

3. Kelly Solutions tells you what is registered for the state for a pest; it has EPA labels, but they are not easy to read: http://kellysolutions.com/

Use commodity bulletins for information about what is registered for a pest:

1. Landscapes: Insect and mite control on woody ornamentals and herbaceous perennials. 2004. Ohio State Bulletin 504: http://ohioline.osu.edu/b504/b504_9.pdf

2. Turf: Management of turfgrass pests weeds, diseases, and insects. 2004. Ohio State Bulletin L-187: http://ohioline.osu.edu/l187/index.html

3. Greenhouse: Ohio Flower Growers Association: http://www.ofa.org/

4. Krischik, V. 2004. Miticides and compatibility with biological control: http://www.entomology.umn.edu/cues/Web/285PesticideCompatibility.pdf

Readings for the lecture:

1. Classes of insecticides, systemic insecticides, injection systems

Pyrethroids are sodium channel lockers: Pyrethroids cause cells to repetitively discharge, which causes paralyses. Pyrethroids affect sodium pump permitting sodium ions to enter nerves (axons) and cause excitation.

Organophosphate and carbamates are cholinesterase inhibitors.

Imidacloprid belongs to the chloronicotinyl chemical class of insecticides. Imidacloprid is also a synaptic nervous system poison. Specifically, this chemical mimics the action of a neurotransmitter called acetylcholine. Acetylcholine normally turns on a nerve impulse at the synapse but its effects are terminated very quickly. Imidacloprid turns on the nerve impulse but cannot terminate it because of its chemical structure.

Insect growth regulators (IGRs) interfere with molting.

Oils and soaps suffocate insects.

Systemic insecticides: imidacloprid (drench and spray) , acephate (Pinpoint), pymetrozine (Endeavor)

Local systemic, translaminar properties: abamectin (Avid), pyriproxyfen (Distance), chlorfenapyr (Pylon), spinosad (Conserve) and acephate (Orthene)

Harrell, M. 2004. Tree injections and implants. In Krischik, V. Ed, IPM of Midwest Landscapes. 315 pp: http://www.entomology.umn.edu/cues/Web/032TreeInjectionsImplants.pdf

Review of tree injections systems in this paper: Know three insecticides that can be injected, such as, abamectin, (Greyhound, Abacide, Vivid II) imidacloprid (Pointer, Imicide), bidren (inject-a-cide B) acephate (Dendrex, Acecaps), and Harpoo (metasystox-R).

2. Imidacloprid in nectar: Is imidacloprid compatible with biocontrol and beneficial insects?

Imidacloprid is a new insecticide chemically related to the tobacco toxin nicotine, which has a long history as an insecticide, which kills by targeting the nervous system.  Imidacloprid is absorbed through the roots and moved systemically around the plant.  Products in landscape and greenhouse include Merit, Marathon, Grub-EX, and Imicide. It is also labeled in agriculture as Admire, Provado, and Gaucho. It is becoming one of the most widely used insecticides, replacing chlorpyrifos for landscape use.

Controversy exists on imidacloprid use in greenhouse, when bumble bees are used to pollinate flowering tomatoes, eggplants, and cucumbers.  The Koppert side effects database indicates that using imidacloprid in flowering plants in the greenhouse is incompatible with pollinators and sap sucking biocontrol organisms, such as Orius. Imidacloprid is no longer used for that purpose in greenhouse.  Controversy also exists on the seed treatment Gaucho, when used in sunflower and canola. Imidacloprid is thought by beekeepers to kill foraging honey bees and bumble bees.

Koppert's side effects data base and choose imidacloprid, imidacloprid DR and Bombus, Chrysoperla, and others: http://www.koppert.nl/e0110.html

Krischik, V., A. Landmark, and G.  Heimpel. 2006. Effects of systemic imidacloprid on the parasitoid Anagyrus pseudococci (Girault) (Hymenoptera: Encyrtidae) when nectar feeding. submitted to Biological Control  Imidacloprid kills nectar feeders.

Rebek, E. J. and C. S. Sadof. 2003. Effects of insecticide applications on the euonymus scale (Homoptera: Diaspididae) and its parasitoid, Encarsia citrina (Hymenoptera: Aphelinidae). J. Economic Entomology 96(2): 446-452: http://docserver.esa.catchword.org/deliver/cw/pdf/esa/freepdfs/00220493/v96n2s27.pdf Imidacloprid does not work well against euonymus scale, an armored scale.

3. Case study environment: Imidacloprid withdrawn from LI, NY due to aquifer contamination

3a. Imidacloprid is restricted use on LI, NY, Branching OUT, Cornell University, Sept 22, 2006    http://branchingout.cornell.edu/2006/BO13(11)/13(11)Scout.html

Imidacloprid Soil Applications
Note: All commercial and professional imidacloprid products are restricted-use in New York State as of 1/1/05, including material purchased prior to that date. Soil injection is not permitted in Nassau and Suffolk Counties, Long Island. Imidacloprid is not available in homeowner products.

3b. Imidacloprid found in aquifer in LI, NY: Spring ‘05-Safety, laws and certifications. Nassau County, NY: http://experts.longisland.com/horticulture/print_article.php?ID=1919

As far as changes in the laws regulating pesticide applications, there has been one major change and one that is in the works. The major change is that the DEC and Bayer have agreed to limit the use of Imidacloprid, the active ingredient in Merit and several other grub controls. Imidacloprid has been reclassified as a restricted use pesticide, and all homeowner uses have been pulled from the market in Nassau County, Suffolk County, Queens and Kings County (Brooklyn). The reason for doing this is that for the past few years trace amounts of Imidacloprid have been showing up in the ground water testing sites that the EPA and the DEC maintain on Long Island. At this point, the amounts are well below the mutually agreed upon threshold limits, but the DEC does not want to take any chances that if left unchecked; we could be facing a serious problem in the future. To this end, the industry has come together with the DEC to limit our uses of this material, and to strictly monitor our own uses to help to minimize the ecological impact that it can have.

4. Case study beneficial animals: Pyrethroids in sediments

4a. Pyrethroids appearing in stream sediments, University of California, California Agriculture, Jan-Mar 2005

http://calag.ucop.edu/0501JFM/scibriefs.html

Weston and colleagues collected 71 sediment samples from rivers, creeks, sloughs and drainage ditches in the Central Valley and exposed amphipods and midge larvae to the sediments. These two organisms are used by the U.S. Environmental Protection Agency (EPA) as indicators of the health of freshwater sediment. Of the sediment samples, 20% killed amphipods at an elevated rate relative to controls and had concentrations of pyrethroids high enough to explain the deaths. The study appeared the journal Environmental Science & Technology in May (Vol. 38, No. 10).

 Pyrethroid use in California has risen due to increased regulation of organophosphates, which pose health threats to workers and cause toxic runoff. Agricultural pyrethroid use in California jumped 25% from 1999 to 2002, although, according to Weston, the increase is only half the picture since it does not take into account the fact that growers are gradually switching to pyrethroids with greater toxicity. About 500,000 pounds of pyrethroids were used in 2002 for nonagricultural uses such as structural and pest control, and landscape maintenance, while more than 250,000 pounds were applied to California farm fields on crops such as cotton, fruit and nut orchards, lettuce, alfalfa and rice.
Despite this increased use, environmental monitoring tends to focus on water sampling, under the assumption that sediment-bound chemicals like pyrethroids are unavailable.

4b.National Coalition Against the Misuse of Pesticides. Daily News Archive
From July 28, 2006       

http://www.beyondpesticides.org/news/daily_news_archive/2006/07_28_06.htm 

Research Shows Pesticide Bans Alone May Lead to New Problems
(Beyond Pesticides, July 28, 2006) Environmentalists, while pleased when toxic pesticides are taken off the market, have long warned that pesticide bans without promotion of non- and least toxic pest management strategies may lead to substitution with other toxic pesticides. On July 26, 2006, Environmental Science and Technology (ES&T) Online reported that since the reduction in residential organophosphate insecticide uses in the early 2000’s, has led to an increase in pesticides formulated with the synergist piperonyl butoxide (PBO), a chemical added to increase the potency and stability of certain pesticides. The concern is that PBO, which is commonly formulated with natural pyrethrum and synthetic pyrethroid insecticides, will react with pesticide residues, drift and runoff already present in the environment, increasing the toxicity and breakdown of these chemicals. The combination of pyrethroids and PBO is also commonly used by communities for mosquito control.

In May 2004, Don Weston, Ph.D., an adjunct professor of ecotoxicology at the University of California, Berkeley, found toxic levels of pyrethroids in creeks flowing through Sacramento, CA. Dr. Weston’s latest paper, published today on ES&T’s Research ASAP website, examines how piperonyl butoxide (PBO) increases the toxicity of these insecticides that are bound up in stream sediments. Although pyrethroids are less acutely toxic to humans than the organophosphates that they have replaced in consumer insecticides, many are linked to chronic effects such as endocrine disruption, and they have not adequately been studied for their impacts on the environment, especially to aquatic invertebrates.

According to ES&T, Dr. Weston’s interest in the environmental effects of PBO was piqued in the summer of 2005 when Sacramento County officials began an aerial spraying program for mosquitoes, to combat West Nile virus. The pesticide was a mix of 60% PBO and 6% pyrethrins. Pyrethrins are natural insecticides produced by certain species of the chrysanthemum plant, and pyrethroids are their synthetic counterparts. Weston wanted to know what would happen when the PBO washed off city streets and into the local creeks where he had already found high levels of pyrethroids. “I felt it was an opportunity that could not be passed up,” he told ES&T, noting that, because of health concerns, California officials rarely conduct aerial spraying anymore. Plus, nobody had ever examined how a pesticide synergist might interact with legacy pesticides.

Dr. Weston found widespread occurrence of PBO at concentrations of up to 4 ppb. Further research showed that this concentration of PBO found that adding the PBO doubled the mortality rate of hyalella, a small bottom-dwelling crustacean. The interaction between synergists like PBO and pesticides already in the creek is something t

5. Case study people: Temik in watermelons

CDC MMWR weekly; April 25, 1986 / 35(16);254-8

http://www.cdc.gov/MMWR/preview/mmwrhtml/00000721.htm

Epidemiologic Notes and Reports Aldicarb Food Poisoning from Contaminated Melons -- California

At 4 a.m., July 4, 1985, three adults who ate a solid green watermelon purchased in Oakland, California, had rapid onset of nausea, vomiting, diarrhea, profuse sweating, excessive tearing, muscle fasciculations, and bradycardia. The most severely ill was a 59-year-old woman who had been receiving digoxin and who, on examination, had a heart rate of 32 and 4-second periods of asystole. The treating physician diagnosed cholinesterase-inhibitor poisoning, and the patient responded rapidly to atropine. The California Department of Health Services (CDHS) had been alerted the day before by Oregon State Health Division officials of similar, although milder, clusters of illness in Oregon associated with ingestion of striped watermelons, possibly of California origin. CDHS notified the San Francisco Bay Area Regional Poison Control Center to be alert for watermelon-associated illness. When the attending physician consulted the Poison Control Center, CDHS was alerted to the outbreak in California.

CDHS contacted 10 California poison-control centers, 20 selected emergency rooms, and a county health department and identified 12 additional cases in different areas of the state. Later on July 4, Oregon officials reported that aldicarb sulfoxide (ASO) had been detected in several melons associated with similar illnesses. ASO is the primary toxic metabolite of aldicarb (Temik), a systemic pesticide not registered in the United States for use on watermelons. In the melon associated with the index cases in California, ASO was found at 2.7 parts per million.

At 1 p.m. that same day, CDHS ordered an immediate statewide embargo on watermelon sales and issued state media advisories recommending that persons refrain from eating watermelons. Because watermelons had become so intermingled in the distribution chain, melons harvested in fields thought to be contaminated could not be separated from other melons. Therefore, on July 7, it was decided to destroy all watermelons in the California distribution chain.

Between July 4 and July 8, CDHS developed a case definition (Table 2). All local health departments and poison-control centers in California participated in a surveillance program for acute illnesses related to melon ingestion. In addition to establishing the extent and severity of illnesses that occurred before July 4, surveillance was continued for illnesses related to melons stickered and presumed to be in compliance with a California Department of Food and Agriculture testing program and sold after July 10. Active surveillance continued until August 31 (Figure 1), although case reports were received through September 30. A total of 1,350 cases were reported from all regions of California and were classified as follows: before July 10, 1,005 reports were received--493 (49%) probable cases, 269 (27%) possible cases, and 195 (19%) unlikely cases; for 48 (5%), information was incomplete. For July 10 and after, 345 reports were received--197 (57%) probable cases, 101 (29%) possible cases, and 40 (12%) unlikely cases; for seven (2%), information was incomplete. There were 18 reports with date of illness missing. The majority (61%) were one-person incidents. Approximately 22% of the illnesses were two-person clusters, 10% were three-person clusters, and 3% were four-person clusters. The remainder involved clusters of five, six, nine, and 13 persons.

Of 250 laboratory tests on melons for ASO, 10 (4%) were positive. These 10 included one ASO-positive stickered watermelon associated with illness reported after July 10; an additional ASO-positive stickered watermelon was reported from Canada. Neither of

Editorial Note: This is the largest recorded North American outbreak of foodborne pesticide illness. In addition to the 692 probable cases reported by California, 10 other jurisdictions in the United States and Canada reported 483 probable or possible cases according to their own case definitions.

Aldicarb is a carbamate insecticide used in citrus groves and potato fields. Unlike organophosphates, which also interfere with cholinesterase activity, inhibition of cholinesterase by carbamates is rapidly reversible.

Aldicarb has the lowest LD50 of any pesticide registered in the United States LD50. Aldicarb sulfoxide has nearly the same LD50. It has been associated with at least two deaths among agricultural workers. It is a highly effective systemic insecticide, readily taken up by the roots and carried into the stem, leaves, and fruit of the plant. Severe and potentially lethal contamination levels can result from intentional or inadvertent misapplication to certain crops, as seen in several prior episodes of foodborne aldicarb poisoning involving cucumbers and mint . It is not registered for use on melons.

6. Case study people: Alar in apple

Environmental Working Group

http://www.ewg.org/reports/alar/alar.html

Alar 9 (daminozide) and children
On Aug. 18, 1998, The New York Times' Personal Health columnist, Jane E. Brody, wrote about an "updated and expanded" edition of "Facts vs. Fears," a report by the American Council on Science and Health reviewing "the greatest unfounded health scares of the last five decades." Brody led with the case any regular reader of the nation's paper of record would recognize as the most notorious example of environmental fear-mongering meeting media hype and producing consumer panic: Alar.

As Brody reminded her readers, Alar - Uniroyal Chemical Co.'s trade name for the compound daminozide - was sprayed on apples so that entire crops would ripen at the same time. In 1989, after 40 million Americans saw a 60 Minutes story about a Natural Resources Defense Council (NRDC) report on Alar as a human carcinogen - one that posed particular risks for children - public outcry forced apple growers to stop using it and Uniroyal to pull it off the market.

According to Brody's column (reprinted in dozens of U.S. newspapers), although "subsequent tests by the National Cancer Institute and the Environmental Protection Agency failed to show that Alar caused cancer," in the wake of the broadcast "millions of alarmed parents panicked and dumped untold gallons of apple juice and bushels of apples [and] the apple industry lost about $375 million." An accompanying photo caption said "the contention" that Alar causes cancer "was based on a 1973 study, but further tests failed to back it up." Brody called the Alar saga "a cautionary tale that should help you realize why it is unwise to leap before you look more closely at what any new study actually means."

Approaching the tenth anniversary of the "60 Minutes" broadcast on Feb. 25, 1989, a review of the record shows:

• Prior to 1989, five separate, peer-reviewed studies of Alar and its chemical breakdown product, UDMH, had found a correlation between exposure to the chemicals and cancerous tumors in lab animals. In 1984 and again in 1987, the EPA classified Alar as a probable human carcinogen. In 1986, the American Academy of Pediatrics urged the EPA to ban it. Well before the 60 Minutes broadcast, public concern had already led six national grocery chains and nine major food processors to stop accepting apples treated with Alar. Washington State growers had pledged to voluntarily stop using it (although tests later revealed that many did not). Maine and Massachusetts had banned it outright.
• On Feb. 1, 1989, acting EPA Administrator John A. Moore, commenting on the preliminary results of Uniroyal's own study of Alar, stated: "There is an inescapable and direct correlation between exposure to UDMH and the development of life-threatening tumors in mice." EPA calculated the lifetime risk of cancer from Alar consumption at 45 in 1 million - 45 times the agency's "negligible" risk level. EPA announced the beginning of a process that would eventually result in a ban on Alar, but before it could take effect, Uniroyal pulled it from the market and its registration, or license for use, soon expired. In 1991 and again in 1992, the EPA reconfirmed its decision that Alar poses an unacceptable risk as a probable human carcinogen, although its new estimate of the cancer risk was about 23 in 1 million - still more than 20 times the acceptable risk level.
• The National Cancer Institute never issued a report clearing Alar as a carcinogen, notwithstanding the ACSH claim to the contrary. In fact, in 1992, an internal ACSH memo lamented, "So many professional organizations, including the National Cancer Institute and American Cancer Society flatly refused to say that the food supply was safe, that pesticide residues in food were not a cause of cancer, that Alar did not pose a risk . . ."¹
• In 1993, a report by the National Academy of Sciences (NAS) validated a central premise of the NRDC report: that infants and young children, who consume a lot of apples and apple products, are particularly susceptible to carcinogens in food. The chair of the NAS study, Dr. Philip Landrigan, said: "NRDC was absolutely on the right track when they excoriated the regulatory agencies for having allowed a toxic material to stay on the market for 25 years." Subsequent reports by the World Health Organization's International Agency for Research on Cancer and the National Toxicology Program of the U.S. Public Health

Readings for the lecture:

1. Discuss the components of the resistance management program for European corn borer in field corn.

Bt-Corn and European corn borer: http://www.ipm.uiuc.edu/fieldcrops/insects/european_corn_borer/btcorn.html

Resistance Management and Bt-corn
Corn growers must accept the very real possibility that European corn borers may become resistant to BT if Bt-corn is planted widely and resistance management tactics are not implemented. Intense selection pressure by any insect-killing agent often results in the development of an insect population that is resistant to that killing agent. By repeatedly exposing a lab colony of European corn borers to BT, researchers at the University of Minnesota already have created a population of corn borers that is resistant to BT

If Bt-corn hybrids are planted widely, European corn borer populations eventually will develop resistance to this very specific insect toxin. Consequently, producers who grow Bt-corn should implement a resistance management plan to slow down the potential onset of resistance. Maintaining "refuges" where corn borers are not exposed to the BT toxin may be the most practical resistance management tactic. In theory, high doses of the BT toxin in Bt-corn kill virtually 100 percent of the corn borers. However, if any borers survive, it is highly desirable to increase the odds that surviving moths (possibly resistant individuals) mate with moths emerging from refuges (susceptible moths).

Refuges include all fields of non-Bt-corn and many other species of plants (including several crops and weeds) on which corn borers can develop. However, resistance management will almost certainly require management of refuges, including entire fields of non-Bt-corn planted adjacent to Bt-corn specifically to provide a refuge for (and source of) susceptible corn borers. Other types of management of refuges may be a block of non-Bt-corn planted within a field of Bt-corn or a designated percentage of rows of non-Bt-corn throughout the field.

The amount of corn that should be used as a refuge within a field or area is not known. However, a managed refuge of 5 to 40 percent may be necessary, depending upon geographical location and the presence or absence of other refuges (wild hosts and non-Bt crops). Throughout most of the Midwest, a 25 percent refuge of non-Bt-corn likely will be necessary to delay the onset of corn borer resistance to the BT toxin.

2. Lindguist, R. 2003. Thrips cocktail http://floriculture.osu.edu/archive/feb03a/Trips03.html

I. Pesticides and pesticide tank mixes that can be used to reduce a well-established western flower thrips population.

A. Mode of action group 1

Orthene 97 TT&O (8 oz/100 gallons). Orthene, an organophosphate insecticide, is labeled on only a relatively few crops, but has been effective against western flower thrips. Rose and orchid growers should use Orthene in their thrips management programs. Mesurol 75WP (8-16 oz/100 gallons). Mesurol is a carbamate insecticide that has been effective against western flower thrips. Do not apply carbamate insecticides following organophosphate insecticide applications, because the two chemical classes have similar modes of activity.

B. Mode of action groups 6 & 18

Avid (8 oz/100 gallons). Avid, a glycoside pesticide, has been effective against western flower thrips. A tank mix with Azatin XL (12 to 16 oz/100 gallons) may improve control.

C. Mode of action groups 3 & 18

Decathlon (1.9 oz/100 gallons) + Azatin XL (12 to 16 oz/100 gallons). This combination of an insect growth regulator (Azatin) and pyrethroid (Decathlon) has been effective against a number of insect pests, including thrips.

D. Mode of action group 5

Conserve SC (6 oz/100 gallons). Conserve is a spinosyn pesticide has been very effective (probably overused as we