Source: UNIV OF IDAHO submitted to
MANAGEMENT OF LYGUS SPP. (HEMIPTERA: MIRIDAE) IN ALFALFA SEED
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0202036
Grant No.
(N/A)
Project No.
IDA01293
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jul 1, 2004
Project End Date
Jun 30, 2009
Grant Year
(N/A)
Project Director
Barbour, J. D.
Recipient Organization
UNIV OF IDAHO
875 PERIMETER DRIVE
MOSCOW,ID 83844-9803
Performing Department
PLANT SOIL & ENTOMOLOGICAL SCI
Non Technical Summary
1)Lygus bugs are a serious pest of alfalfa seed in idaho and the pacific northwest 2)Effective biological management of lygus bugs could benefit alfalfa seed production by reducing damage to alfalfa seed and by reducing negative impacts of management on pollinators and beneficial natural enemies and delay or prevent the development of insecticide resistance. The goal of this proposal is to conduct studies investigating the potential for achieving lygus bug management and pollinator safety through the complementary use of selective insecticides and crop habitat management.
Animal Health Component
(N/A)
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2113110113033%
2153110113034%
2163110113033%
Goals / Objectives
The primary goal of this proposal is to conduct studies investigating the feasibility of enhancing lygus bug management in alfalfa seed through several complementary approaches. The individually low levels of lygus bug management provided by newer, more selective alternative compounds and that provided by natural enemies of lygus bugs will be combined in an attempt to provide acceptable levels of lygus management in large plots of alfalfa grown for seed. We will attempt to further enhance natural enemy numbers in these studies through modification of crop habitat (border treatments). Specific objective are: I. Conduct small plot field studies to evaluate selected, selective pesticides for efficacy against lygus bugs in alfalfa seed. II. Evaluate compounds showing reasonable efficacy against lygus bugs in objective I for safety to alfalfa leafcutting bees and to important natural enemies of lygus bugs. a.Conduct laboratory studies establishing LD50 &/or EC50 values of selected pesticides to alfalfa leafcutting bees, damsel bugs, and bigeyed bugs, P. howardi and lygus bugs. b.Conduct field and laboratory studies to establish residual toxicity (RT25) of selected compounds applied to alfalfa foliage to leafcutting bees, damsel bugs, and bigeyed bugs, P. howardi and lygus bugs. III. Conduct field experiments examining the effects of selected pesticides on alfalfa leafcutting bee biology behaviors that might affect pollination and seed production. IV. Conduct studies examining the biology and ecology of P. howardi towards determining this parasitoid's potential to provide effective biological management of lygus bugs in alfalfa seed. a.Continue survey work examining the geographic and host range of P. howardi in the Pacific Northwest. b.Conduct field studies examining the effect of cultivation practices on survival of P. howardi overwintering in alfalfa seed fields. c.Conduct field studies examining the effects of pesticides and habitat (border) management on biological management of lygus bugs in alfalfa seed. V. Provide research findings to growers in a timely manner through newsletters, web site(s), or other appropriate means.
Project Methods
Pesticide trials will be conducted annually on established alfalfa seed at the Parma R&E Center, Parma, ID. Treatments will include several of the newer pesticides, a standard pesticide treatment (e.g. bifenthrin + dimethoate) and an untreated control. The number and chemistries of pesticides tested will vary from year to year based on availability and potential efficacy of compounds. Replicated laboratory experiments will be conducted to establish LD50/LC50 values for selected compounds to alfalfa leafcutting bees, damsel bugs, and bigeyed bugs, P. howardi and lygus bugs. Experiments examining the effects of currently labeled and new pesticides on alfalfa leafcutting bee behaviors that might affect pollination and seed production will be conducted in an established alfalfa seed field at the Parma Research and Extension Center. Conduct field studies examining the effects of pesticides and habitat (border) management on biological management of lygus bugs in alfalfa seed. Results will be provided to regional alfalfa seed industry personnel through a variety of media: through existing web-based tools, through written and oral reports and presentations provided to local and regional growers, through the publication of extension articles (e.g. U of I Current Information Series) as hard copy &/or as web-based documents, and through oral and poster presentations at regional field day tours and workshops to growers, pest management advisors and extension educators, conducted by the PD and Co-PD's.

Progress 07/01/04 to 06/30/09

Outputs
OUTPUTS: Empirical evidence from grower fields continued to indicated that use of of the pesticide Rimon (novaluron) was sometimes associated with low return of alfalfa leafcutting bees (ALCB)in alfalfa seed production. Laboratory studies conducted in 2008 and 2009 indicated that ALCB larvae treated with field rates of novaluron suffered at least 90% higher mortality than untreated bees. Adult bees fed a sucrose solution containing Rimon had a greater than 90% reduction in production of progeny (depositied no eggs or inviable eggs). Fields studies conducted in 2009 in parallel with the laboratory studies showed an increase in the % pollen balls and a decrease in live ALCB bee larve in nest blocks from fields treated with Rimon comapred to those from fields treated with alternative pesticides. PARTICIPANTS: Individuals: James D Barbour, Erin Hodgson, Theresa Pitt-Singer; PIs, Joyce Ashcraft; Research Technician, Noemi Fernandez; Research Support Scientist Partner organizations: USDA-ARS Pollinating insect-Biology, Management, Systematics Research Laboratory. Utah State University, Idaho alfalfa and clover seed commission TARGET AUDIENCES: TARGET AUDIENCES: The target audience of these efforts is alfalfa seed growers and alfalfa seed companies operating in Idaho,and the western US, and their field personnel. Efforts consisted of extension and outreach to target audiences through prentations at grower meetings and workshops, research reports and face-to-face contacts. PROJECT MODIFICATIONS: Some research and extension effort redirected to understanding the role of Rimon in reduced ALCB return and to formulating new recommendations for use of Rimon for managing lygus bugs in alfalfa seed.

Impacts
There has been increased use of these three low-risk compounds for managing lygus in alfalfa seed grown in Idaho. There is also increasing concern about the potential effects of novaluron on alfalfa leafcutting bee return. These concerns have cause us to redirect our research efforts during the 2008 and 2009 crop years to focus on the potential impact of novaluron on alfalfa leafcutting bees and createing new recommendations for the use of Rimon for managing lygus bugs in alfalfa seed.

Publications

  • No publications reported this period


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Several low risk pesticides (metaflumazone, novaluron, flonicamid) were tested for efficacy against lygus bugs and were shown to provide effective control lygus bug control. Some empirical evidence from grower fields indicated that use of one of the compounds, novaluron, was associated with low return of alfalfa leafcutting bees (ALCB). Laboratory studies indicated that ALCB larvae treated with field rates of novaluron suffered higher mortality than untreated bees. Fields studies conducted in parallel with the laboratory studies, however, showed no difference in ALCB return between fields treated with novaluron and fields treated with other grower selected insecticides. PARTICIPANTS: Individuals: James D Barbour, Erin Hodgson, Theresa Pitt-Singer; PIs, Joyce Ashcraft; Research Technician, Noemi Fernandez; Research Support Scientist Partner organizations: USDA-ARS Pollinating insect-Biology, Management, Systematics Research Laboratory. Utah State University: TARGET AUDIENCES: The target audience of these efforts is alfalfa seed growers and alfalfa seed companies operating in Idaho,and the western US, and their field personnel. Efforts consisted of extension and outreach to target audiences through prentations at grower meetings and workshops, research reports and face-to-face contacts. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
There has been increased use of these three low-risk compounds for managing lygus in alfalfa seed grown in Idaho. There is also increasing concern about the potential effects of novaluron on alfalfa leafcutting bee return. These concerns resulted in a redirection of our research efforts during the 2008 and 2009 crop years to focus on the potential impact of novaluron on alfalfa leafcutting bees.

Publications

  • No publications reported this period


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Several low risk pesticides(metaflumazone, novaluron, flonicamid) tested for efficacy against lygus bugs provided moderate lygus bug control and proved less toxic to alfalfa leafcutting bees and to lygus bug predators than currently labeled compounds. These compounds have potential, either alone or in combination with natural enemies, to provide effective control. Under current management practices, natural enemies alone cannot provide economic lygus bug control. Results of studies have been desseminated via presentations to growers and field persons, peer reviewed exension publication, peer reviewed book sections and refereed abstracts/proceedings. PARTICIPANTS: Individuals: James D Barbour; PI, Joyce Ashcraft; Research Technician, Noemi Fernandez; Research Support Scientist Partner organizations: USDA-ARS Pollinating insect-Biology, Management, Systematics Research Laboratory TARGET AUDIENCES: The target audience for this project is idaho alfalfa seed growers, seed companies operating in Idaho, and their field personnel. Scince based knwledge resulting form this project was deseminated to the target audience via extension and aoutreach efforts: preentations and peer reviewed extension publications.

Impacts
As a result of tests conducted by us and other researchers in this and previous years, flonicamid and acetamiprid received section 24c registration in Idaho for management of lygus in alfalfa seed during the 2007 crop year. These compounds were used by alfalfa seed growers in 2007 and likely replaced aome applications of more broadly toxic insecticides for lygus control

Publications

  • Baird, C.R. and Barbour, J.D. 2007. Beneficial Organisms: True bug predators. In: (W. O. Lamp, R. Berberet, D. Johnson, L. Higley, & C. Baird, Eds.), Handbook of Forage and Rangeland Insects. Entomological Society of America, Lanham, MD and The American Phytopathological Society Press. 188 pp.
  • Baird, C.R. and Barbour, J.D. 2007. Beneficial Organisms: Pollinators. In: (W. O. Lamp, R. Berberet, D. Johnson, L. Higley, & C. Baird, Eds.), Handbook of Forage and Rangeland Insects. Entomological Society of America, Lanham, MD and The American Phytopathological Society Press. 188 pp.
  • Baird, C.R. and Barbour, J.D. 2007. Injurious Arthropods: Lygus bugs. In: (W. O. Lamp, R. Berberet, D. Johnson, L. Higley, & C. Baird, Eds.), Handbook of Forage and Rangeland Insects. Entomological Society of America, Lanham, MD and The American Phytopathological Society Press. 188 pp.
  • Baird, C.R. and Barbour, J.D. 2007. Injurious Arthropods: Seed Chalcids. In: (W. O. Lamp, R. Berberet, D. Johnson, L. Higley, & C. Baird, Eds.), Handbook of Forage and Rangeland Insects. Entomological Society of America, Lanham, MD and The American Phytopathological Society Press. 188 pp.


Progress 01/01/06 to 12/31/06

Outputs
Mortality response of Lygus hesperus collected from grower fields was tested against carbamate, pyrethroid and organophosphate pesticides used for their control in alfalfa seed. Lygus hesperus mortality to pyethroids varied among grower fields early and late season for bifenthrin, but not for lambda cyhalothrin. Carbamate response varied among grower fields late season for formetanate hydrochloride, but did not vary among grower fields for methomyl. Mortality response to organophosphates varied late season, but not early season, for both methidathion and oxydematon-methyl. These results indicate that L. hesperus sensitivity to these pesticides varies among pesticide classes and seasonally. Novaluran was tested in grower fields and flonicomind was tested in small plot trials for efficacy against L. hesperus. Both are reduced risk compounds that are more IPM-friendly than traditional compounds used to control lygus in alfalfa seed, and both compounds reduced L. hesperus numbers and/or increased seed yield compared to control treatments. We have demonstrated in both first and second year alfalfa seed significant interactions of plant spacing with available or residual Phosphorus. The results suggest producers have little reason to apply Phosphorus for alfalfa seed production at plant spacings normally used, especially when residual phosphorus is maintained at levels above those necessary for near maximum vegetative growth.

Impacts
This research provides information on lygus bug sensitivity to pesticides currently labeled for their control in alfalfa seed and will aid in the development of resistance management programs to extend their use. Results of efficacy trials are expected to lead to the registration of low risk pesticides for L. hesperus control in alfalfa seed. It is expected that the use of these compounds will increase the potential for management of L. hesperus using biological control by predaceous and parasitic natural enemies. Novaluran (Rimon 0.83EC) received a section 24c registration in 2006 for control of lygus in alfalfa seed. The results of phosphorus fertilization experiments will used to revise the Idaho Fertilizer Guide if the third year trials confirm the response observed in the first two years.

Publications

  • No publications reported this period


Progress 01/01/05 to 12/31/05

Outputs
Residual toxicity (RT25) studies of alfalfa foliage treated with acetomiprid, clothianidin, indoxicarb, novaluron, thiacloprid, were conducted with alfalfa leaf cutting bees and for several natural enemies of lygus bugs (bigeyed bugs, damsel bugs and minute pirate bugs). Residual toxicity of all compounds except clothianidin (24h) thiacloprid (48) was less then 8 hr and to alfalfa leafcutting bees, bigeyed bugs and damsel bugs. The RT25 is of all compounds to these insects was one half or less than that of bifenthrin (96hr). All compounds exept novaluron (4h) have equivalent and high residual toxicity to minute pirate bugs (96h). Peristenus howardi parasitized lygus bugs from 3 crop and 4 non-crop hosts sampled with peak parasitism rates ranging from 5% to 80%. P. howardi accounted for about 75% of the observed lygus parasitism. Other, unknown Peristenus and non-Peristenus species accounted for the remaining parasitism.

Impacts
This information will help us to design cropping systems that increase the chance of successful biological control of lygus if any of the lower risk compounds tested are registered for use against lygus bugs in alfalfa seed. This work also increases our understanding of the interaction of Peristenus howardi with lygus bugs and lygus bug host plants.

Publications

  • Barbour, J.D. 2005. Effects of crop management practices on pollinators and pollination in alfalfa seed and other Pacific Northwest crops. P. 23. Proceedings of the 2005 Winter Seed School held 1/3-/05-2/1/05. Boise ID.
  • Seymour, L.M, Mowry, T.M., Day, W.H. and Barbour, J.D. 2005. Parasitism of Lygus spp. (Heteroptera: Miridae) nymphs in the alfalfa seed growing region of the Pacific Northwest. J. Insect Science, Accepted
  • Barbour, J.D., Seymour, L.M. and Mowry, T.M. 2005. Determining parasitism of Lygus spp. by Peristenus spp. in crop and non-crop hosts using polymerase chain reaction. P. 57 Proceedings of the Ecology and Management of Lygus Plant Bugs Symposia held 1/30/05-2/3/05 Ottwa, Ontario, CA.