RESEARCH REPORTS
78th ANNUAL PACIFIC NORTHWEST INSECT MANAGEMENT CONFERENCE
HILTON HOTEL 921 SW 6th Ave. PORTLAND, OREGON JANUARY 7 & 8, 2019
**These are research reports only, NOT management recommendations.
1
TABLE OF CONTENTS
78th ANNUAL PACIFIC NORTHWEST INSECT MANAGEMENT CONFERENCE January 7 & 8, 2019
AGENDA …...... 4
PAPERS Note: “*” denotes a student paper. Students present their reports together, in a separate block of time, on Tuesday morning (see Agenda)
SECTION I: Invasive Pests, Emerging Pests, and Hot Topics of Interest A. Schreiber. THE STATE OF PEST MANAGEMENT IN LEGAL CANNABIS PRODUCTION IN WASHINGTON………………...... 6
C. Hedstrom. UPDATE ON CURRENT ERADICATION PROGRAMS BY THE OREGON DEPARTMENT OF AGRICULTURE ……...…………………………….…………….………...... 7
*C.S. Bezerra Da Silva, K.R. Park, R.A. Blood, V.M. Walton. INTRASPECIFIC COMPETITION AFFECTS THE PUPATION BEHAVIOR OF SPOTTED-WING DROSOPHILA (DROSOPHILA SUZUKII) IN NATURAL AND ARTIFICIAL DIETS…………………………………………..……………………………………….....10
C. Park. A BRIEF HISTORY OF THE BIOLOGICAL CONTROL OF WEEDS IN OREGON………………………..11
Colton, AJ., Denver, D.R., Howe, D.K., and Mc Donnell, R.J. DISCOVERY OF THREE SPECIES OF SLUG- KILLING NEMATODES IN OREGON AND AN ASSESSMENT OF THEIR LETHALITY TO THE KEY SLUG PEST, DEROCERAS RETICULATUM (POSTER)………………………………………….………...…13
D.B. Walsh. RODENTICIDE EFFICACY STUDIES WITH CHLOROPHACINEIN AND ZINC PHOSPHIDE IN WASHINGTON STATE HOPYARDS………………………….…………………….14
D.M. Lightle, C. Borkent, V. Popescu and C. Pickett. BROWN MARMORATED STINK BUG NATURAL ENEMIES IN CALIFORNIA……………………………………………………………………………..…………………16
*G. Galindo, C. Alba, T. Neill, W. Mahaffee, J. Lee. BOTRYTIS AND SPOTTED WING DROSOPHILA…………………………………………………………………………………………………..17 J.C. Lee, H. McIntosh, G. Galindo. HELPING OUT THE SAMURAI WASP (POSTER)……………………………...21 M.L. Klein, T. Chastain, R. J. Mc Donnell. ACUTE TOXICITY OF ESSENTIAL OILS TO ADULTS OF THE PEST SLUG DEROCERAS RETICULATUM IN LABORATORY AND GREENHOUSE BIOASSAYS (POSTER)………………………………………………………………………………………………………..22
S.J. Ahn, K.M. Donahue, M.Y. Choi. RNAi TECHNOLOGY: CURRENT STATUS AS AN ALTERNATIVE PEST MANAGEMENT TOOL TO CONTROL SPOTTED WING DROSOPHILA……………………………………………………………………………….………………….23
T. Marie, D. Lowenstein, E. Rudolph, A. Mugica, H. Andrews, N. Wiman. TESTING COMPATIBILITY OF A BIOCONTROL AGENT OF HALYOMORPHA HALYS WITH PEST MANAGEMENT REGIMES IN PACIFIC NORTHWEST HAZELNUTS…………………………………………………………………….….26
SECTION II: Bees and Pollinators P. Chakrabarti, J. T. Morré, L. Yang, C. S. Maier and R. R. Sagili. THE OMICS APPROACH TO HONEY BEE NUTRITION…………………………………………………………………………………………………..…29 2
SECTION III: Environmental Toxicology and Regulatory Issues B. Gerdeman, J. DeFrancesco, C. Holladay and H. Spitler. INSECTICIDE/MITICIDE/ FUNGICIDE DECLINE IN PNW CANEBERRIES…………………………………………………………………………………………..33
SECTION IV: Field Crop Pests A. Adesanya and D. Walsh. QUANTIFYING ACARICIDE RESISTANCE STATUS IN SEVERAL CALIFORNIA BERRY PLANTATIONs TETRANYCUS URTICAE POPULATIONS TO BIFENAZATE, HEXYTHIOZOX, AND ABAMECTIN……………………………………………………………………………………………..38
D. Walsh and D. Groenendale. LYGUS EFFICACY TRIALS N ALFALFA PRODUCED FOR SEED 2018………………………………………………………………………………………………………………42
D.B. Walsh. 2018 ACARICIDE EFFICACY TRIALS IN WASHINGTON STATE HOPYARDS……………………..44
G. Shrestha, J. Antwi, and S.I. Rondon. LANDSCAPE EFFECT ON LYGUS MOVEMENT AND CROP SELECTION………………………………………………………………………………………………………46
T. Waters, A. Adesanya and D. Walsh. EVALUATING INSECTICIDE RESISTANCE IN ONION THRIPS…………………………………………………………………………………………………………..47
SECTION V: Potato Pests A. Schreiber and T. Waters. CAN THE PNW REESTABLISH POTATO IPM PROGRAMS……...……………..…….49
D. I. Thompson, and S. I. Rondon. TIMING APPLICATIONS FOR CONTROL OF LYGUS SPP. IN POTATOES………………………………………………………………………………………………………50
*M. Montes de Oca, and S. I. Rondon. THE POTATO PSYLLID IN THE COLUMBIA BASIN: PEST MANAGEMENT STRATEGY……………………………………………………………………………..….51
*P. Yang, M.S. Crossley, and S. I. Rondon. EFFECT OF SELECTED INSECTICIDES AGAINST COLORADO POTATO BEETLES AND ITS NATURAL ENEMIES IN THE COLUMBIA BASIN……………………………..……52 SECTION VI: Pests of Wine Grapes & Small Fruits A. Schreiber and S. Song. CONTROLLING SPOTTED WING DROSOPHILA IN ORGANIC BERRIES……...…….54
G. Alton. SPOTTED WING DROSOPHILA POPULATION CONTROL WITH PRECISION GUIDED STERILE MALES: PROOF-OF-CONCEPT IN DROSOPHILA MELANOGASTER………………………..……….….58
M-Y. Choi, J.C. Lee. PHYSIOLOGICAL EFFECT OF ERYTHRITOL FOR SPOTTED WING DROSOPHILA…………………………………………………………………………………………….…….59
*J.C. Lee, L. Komnenus. ANTIMICROBIALS FOR SPOTTED WING DROSOPHILA CONTROL………………….60
J.C. Lee, Man-Yeon Choi. FIELD TESTS OF ERYTHRITOL FOR SPOTTED WING DROSOPHILA...... 61
*K.V. Graham and J. Lee. PRELIMINARY RESULTS ON THE EFFICACY OF PLANT VOLATILES IN THE BIOCONTROL OF THE AZALEA LACE BUG…………………………………………………………….…62
SECTION VII: Pests of Turf and Ornamentals R. Rosetta. SURVEY OF SPIDER MITES AND NATURAL ENEMIES ON ‘AUTUMN BLAZE’ MAPLE IN OREGON NURSERY PRODUCTION……………………………………………………………………...65 SECTION VIII: New and Current Product Development K. Tso. CID BIO-SCIENCE, INC.: A REVIEW OF INSTRUMENTATION AVAILABLE TO EVALUATE PLANT RESPONSE TO INSECT DAMAGE……………………………………………………………………………..………69
SECTION IX: Extension & Consulting: Updates & Notes from the Field J. Green, T. Thompson, N. Anderson, C. Bouska, and W. Jessie. REGIONAL MONITORING FOR TRUE ARMYWORM………………………………………………………………………………………………..….72 3
AGENDA 78th ANNUAL PACIFIC NORTHWEST INSECT MANAGEMENT CONFERENCE Hilton Hotel, Portland, Oregon January 7 & 8, 2019
(Each presentation is allotted 15 minutes)
MONDAY, JANUARY 7th
Registration 9:00AM Call to Order Business Meeting 10:00AM (Judge’s for Student Competition; Tumblebug Committee, Recognition to Sponsors)
Section I (5 reports) 10:30AM
Lunch (on your own) 11:45AM
Section I (5 reports) 1:00PM Section II (1 report) Section III (1 report)
Break 2:45PM
Section IV (5 reports) 3:00PM 4 Adjourn 4:30PM TUESDAY, JANUARY 8th
Registration 8:15AM
Call to Order 8:40AM
Student Presentations (6 reports) 8:45AM
Section V (2 reports) 10:00AM Section VI (4 reports)
Break 11:15AM
Section VII (1 report) 11:30AM Section VIII (1 report) Section IX (1 report)
Final Business Meeting
Adjourn 12:30PM
4
SECTION I Invasive Pests, Emerging Pests, and Hot Topics of Interest
5
THE STATE OF PEST MANAGEMENT IN LEGAL CANNABIS PRODUCTION IN WASHINGTON
Alan Schreiber Paladin Agricultural Research Inc. 2621 Ringold Road Eltopia, WA 99330 (509) 266 4348 [email protected]
Cannabis production is no different from other agricultural crops in that it can become infested with a variety insect, mites and disease. Cannabis production is different from all other agriculture because it is illegal to federally register a pesticide for control of insects and disease. The Washington State Department of Agriculture has developed a list of products that are considered not illegal to use on cannabis in Washington. Many of these products have no practical pest management value. Many other of these products have limited efficacy, short residual or other attributes that limit their usefulness to cannabis growers. Due to the expectation of superior quality and the extremely high value of their crop, cannabis growers are under heavy pressure to control insects, mites and diseases. Due to the combination of these factors growers are using a wide array of pest management products and practices, some of which may be illegal and may pose a risk to pesticide applicators, cannabis workers and cannabis consumers. This situation is exacerbated by a federal probation on Washington State University and USDA conducting pest management research, development of alternatives to pesticides, pesticide applicator training or training on worker protection from pesticides. The lack of appropriate mechanisms for pesticide applicator and worker protection standards training, the lack of adequate crop protection tools and the absence of traditional research and extension outreach programs has created a “Wild West” mentality where any kind of pest management tactics can occur. The void of traditional pest management research, extension and appropriate tools has created serious and potentially dangerous conditions in cannabis production. This is not a new occurrence. Following a pesticide label has historically not been among the most important considerations in the illegal production of cannabis. What is difference is the cannabis is legally available for medical purposes for the large majority of the U.S population and is completely legal in several states. The widespread legalization of cannabis is bringing historical cannabis pest management practices into public view. Recent state investigations in Colorado, Oregon and Washington has indicated that illegal pesticide use is not uncommon in the cannabis industry.
6
UPDATE ON CURRENT ERADICATION PROGRAMS BY THE OREGON DEPARTMENT OF AGRICULTURE C. Hedstrom Oregon Department of Agriculture, Insect Pest Prevention and Management 635 Capitol St NE, Suite 100, Salem, OR 97301 [email protected]
Japanese Beetle 2018 Japanese beetle treatment operations:
• ~2,200 acre area treated with granular insecticide, ~5,800 residences • Treated lawn areas, but also ornamental planting beds (beds not treated in 2017) • April 2 to June 2 2018 (Acelepryn G), Sept. 5 and Oct. 10 (Grubgone! BtG) • Treated 31 residences in Oakland, OR (Douglas County, 10 beetles detected 2017) • Residents supportive o 5,113 “yes” consent forms collected (~88%) o 80 “no” forms returned (1.3%) o 25 medical exemptions requested and granted o 400 non-response warrants served (7%); 448 warrants requested
2017 Japanese beetle treatment / 2018 trapping Results
• Acelepryn takes 90 days to become active in the soil, and effects grubs hatching in the soil in the fall; 2017 treatment success is measured by 2018 trapping results • 2017 Treatment area comparisons: o In the 2017 treatment area we captured 22,688 beetles. o In the same area in 2018, we captured 13,251 beetles, ▪ 41.6% population reduction o 2017 average beetles per trap: 34.7 o 2018 average beetles per trap: 21.5 ▪ 37.7% per trap reduction • Numbers are going in the right direction, but still a lot of work to do • Overall Numbers: o 2017: 23,454 beetles detected o 2018: 16,461 beetles detected o 2018 Japanese beetle detections at PDX (within normal range that we see annually), Swan island (reduced from last year). o 1 beetle detected in Oakland, OR (Reduction not a result of our treatment)
2019 Japanese beetle Proposed Operations
• Larger treatment area as 2018, up to 8500 residences • Consent gathering begins in January 2019; Treatment in Spring • Beetles do not appear to be spreading quickly from the area, but containment still a concern o Yard debris quarantine in part of Washington County will continue in 2019.
7
Gypsy Moth Oregon Department of Agriculture (ODA) routinely conducts extensive survey programs for gypsy moth (GM, Lymantria dispar dispar) and its Asian strain (Asian gypsy moth, AGM, Lymantria dispar asiatica). Both moths can be detected with the same trap and lure. Survey traps are placed at a density of 1-4 traps per square mile. A GM detection in any area results in delimitation trapping for the following two years at higher trap densities. If no moths are detected in those two years, delimitation trapping is completed.
2016 Delimitation Results:
• Lane County: Two GM were detected in Lane Co. in 2016. Delimitation trapping in 2017 and 2018 did not detect any moths at this site, and is now completed. • Josephine County: 4 GM were detected in Josephine Co. in 2016. These were detected in the delimitation areas from 2013, 2014, and 2015. Delimitation trapping in 2017 and 2018 did not detect any moths at this site, and is now completed. • Multnomah County: Delimitation trapping for 2 AGM detected in 2015 did not detect addition AGM moths in 2016, 2017, or 2018 and is now completed. The eradication program conducted in 2016 is considered successful.
2017 Delimitation Results:
• Lane County: 2 GM were newly detected SE of Eugene in 2017. Delimitation in 2018 did not detect GM at this site. A second year of delimitation will continue at this site in 2019. • Josephine County: 1 GM was detected in Josephine County SE of Cave Junction in 2017. Delimitation trapping in 2018 did not detect any GM at this site. A second year of delimitation will continue at this site is 2019. • Multnomah County: 3 GM were detected in Multnomah County in Portland in 2017. Delimitation trapping in 2018 did not detect any GM at these sites in 2018, however a detection did occur in close proximity (2.23 mi/3.59 km) to the overlapping delimitation areas (see below). A second year of delimitation will continue at these sites in 2019. • Benton County: 5 GM were newly detected at 2 nearby sites in Benton County in 2017. Delimitation and add-on traps placed in 2018 detected 27 GM.
An eradication program is being planned for 2019 and is currently in early planning stages. Two egg mass searches in August and December 2019 did not recover any masses. The proposed site consists of two apartment complexes occupied by university students, some likely from infested states. The actual introductory pathway is unknown and may be impossible to determine, as this is the second year of detection in an area of generally temporary residents (e.g. college students). The proposed eradication area is 45 acres, and will consist of two ground applications of Bacillus thuringiensis Kurstaki (BtK).
2018 Detection Survey Results (New Detections):
• 2018 Statewide survey: ODA placed approximately 10,899 AGM and 5,080 GM traps (total 15,979 traps) in 31 counties throughout Oregon in 2018 • Deschutes County: 1 GM was detected in Deschutes County in Bend in 2018. Delimitation trapping will begin in 2019. The source is currently unknown. • Lane County: 2 GM were found at 2 sites approximately 1 km apart in west Eugene. Delimitation trapping will begin in this area in 2019. The source is currently unknown. These sites are outside of the delimitation area for GM detected in Lane County in 2017.
8
• Marion County: 2 GM were detected at 2 new sites in Marion County in 2018; 1 GM in Champoeg State Park and 1 GM in Keizer in a residential area. Delimitation trapping will begin at these sites in 2019. The sources are currently unknown. • Multnomah County: 3 GM were detected at 3 new sites in Multnomah County in 2018; 1 in North Portland (Piedmont Neighborhood), 1 in NW Portland (industrial area; close to 2017 GM delimitation area), 1 in Dixie Mountain/Scappoose Area. Delimitation trapping will begin at these sites in 2019. The sources of these GM are currently unknown.
9
Intraspecific Competition Affects the Pupation Behavior of Spotted-Wing
Drosophila (Drosophila suzukii) in Natural and Artificial diets
C.S. Bezerra Da Silva, K.R. Park, R.A. Blood, V.M. Walton
Department of Horticulture, Oregon State University, 4017 Agricultural and Life Sciences Building,
Corvallis, OR 97331, USA
[email protected], [email protected], [email protected],
Spotted-wing drosophila (SWD, Drosophila suzukii) pupates attached (in, on fruit) or detached (off fruit) to their host, but factors influencing such decision are unknown. Females of this species often lay multiple eggs per host fruit thus exposing their offspring to intraspecific competition (IC). IC may cause stress, cannibalism, and affect survival and reproduction. Here, we hypothesized that IC motivates detached pupation in SWD as a means to escape the effects of IC. In laboratory, IC correlated positively to detached pupation in both cornmeal medium and blueberry fruit. Males were more prone to detached pupation than females. In blueberry, IC-exposed larvae pupated farther away from their host fruit relative to singly-developed individuals. Detached pupation buffered the negative effects of IC on SWD survival and fitness. Shorter egg-pupa development, higher pupa- adult survival, and larger adult size were found in individuals that displayed detached pupation relative to those that pupated attached to the fruit. These findings demonstrate that SWD larvae select pupation sites based on IC and such strategy is associated with improved survival and fitness. This information contributes to a better understanding of SWD biology and behavior, giving insights to the development of improved practices to manage this pest in the field.
This work and other related studies are in preparation for submission to a peer-reviewed journal.
10
A Brief History of the Biological Control of Weeds in Oregon 2018, Colin Park, UNL Masters in Entomology Candidate
The first documented release of an imported natural enemy (classical biocontrol agent) to control an exotic terrestrial plant (designated noxious weed) in Oregon occurred in Corvallis in 1943 with the introduction of a St. Johnswort leaf beetle. In the 75 years since then, 78 species of biocontrol agents, mostly insects, have been introduced to control 27 different plant species in the state. Due to host range cross-over in closely related weeds, this has resulted in 120 agent-host combinations.1 In a recent comprehensive review for the Oregon Department of Agriculture, Noxious Weed Control Program, 26 species of these biocontrol agents were found to be both widespread and effective in controlling their target host(s), a rate of 1/3rd, and the state program overall was estimated to have a net annual benefit of 14.6 M$ in 2018 USD.2 Early work in Oregon on St. Johnswort in the 1940s and then tansy ragwort starting in the 1950s were both considered highly successful ecologically and economically.3 Biocontrol of tansy ragwort alone is estimated to save 5-10 M$ in the state each year.4 These ‘classics’ helped to spur broad interest and support for developing this technology, catapulting Oregon into one of the world’s foremost advocates for using natural enemies to control invasive species across taxa. The rate of development and permitting, culminating in new biocontrol agent introductions, increased steadily in the subsequent decades, in Oregon and globally, peaking in the mid-1990s.1 In the late 1990s concern for impacts on native thistles lead to call for a slowing of new introductions, in order to review research protocols for evaluating direct feeding by agents on native plant species. More rigorous and extensive host-specificity testing, greater transparency in the permit granting process, as well as enhanced consultation with natural resource management agencies and the public have resulted. Additionally, indirect negative effects on endangered species (ESA) became a proven area of concern starting in about 2010, following litigation that resulted from the ESA protected Southwest Willow Flycatcher (Empidonax traillii extimus) loosing crucial nesting habitat—in part provided by invasive Tamarisk plants—due to population reductions cause by an exotic leaf beetle approved for release in the US.5 USDA APHIS which oversees the permitting process for exotic plant pests, immediately suspended all permits for the continued movement of this agent, and further slowed the approval of new agents while interagency reviews were conducted on how to better predict such secondary trophic effects on ESA protected species. In sum, in order to respond to the concerns that have resulted from improved ecological understanding and concern, and to develop more transparent protocols for the approval of new biological control agents, a major reduction in the approval of new agents occurred in recent decades, while policy improvements were considered and implemented. During this same time, several breakthroughs have improved risk assessment testing:
• Many decades of applied biocontrol results now provide real world statistics on predictive modelling, showing a high rate of risk prediction success in pre-release studies.6 • Improved phylogenetic understanding of the plant kingdom allow for more precise targeting of potential non-target plant species of concern that will require study prior to permitting.
11
• New innovations in simulating multi-choice host testing under lab conditions enable more accurate forecasts of proposed agent behavior and risk to non-target host populations.7 • Additionally, efforts to also quantify what positive effects on threatened and endangered species prospective biocontrol agents might have in the environment are now also being included in the permitting decision-making framework. These refinements in assessment methods, combined with continued demand for alternatives to pesticide use from the public, as well as numerous comprehensive retrospective reviews of the state of the science, have very recently resulted in the renewed investment and approval of new agents for the biocontrol of weeds both in Oregon and globally.8, 9
Works Cited: 1: Oregon Department of Agriculture Biocontrol Release Database, 2018 2: The Research Group, LLC. 2014. Economic Impact from Selected Noxious Weeds in Oregon. Prepared for Oregon Department of Agriculture, Noxious Weed Control Program. Corvallis, OR 3: Richter, P.O. 1966. Biological Control of Insects and Weeds in Oregon. Agricultural Experiment Station. Oregon State University. Technical Bulletin No. 90. Corvallis, OR 4: Coombs, E.C, H. Radtke, D.L. Issaacson, S.P. Snyder, 1996. Economic and Regional Benefits from the Biological Control of Tansy Ragwort in Oregon. IX International Symposium on Biological Control of Weeds 5: Hatten, J.R. 2016. A Satellite Model of Southwestern Willow Flycatcher Breeding Habitat and a Simulation of Potential Effects of Tamarisk Leaf Beetles, Southwestern United States. Geological Survey Open-File Report http://dx.doi.org/10.3133/ofr20161120 6: Schwarzländer, M., H.L. Hinz, R.L Winston, M.D. Day, 2018. Biological Control of Weeds: An Analysis of introductions, Rates of Establishment and Estimates of Success, Worldwide. BioControl 7: Park, I., S.D. Eigenbrode, S.P. Cook, M. Schwarzländer, 2018 Examining Olfactory and Visual Cues Governing Host-specificity of a Weed Biological Control Candidate Species to Refine Pre- release Risk Assessment. BioControl
8: Messing, R. H., M. G. Wright, 2006. Biological Control of Invasive Species: Solution or Pollution? Frontiers in Ecology and the Environment 9: Oregon Department of Agriculture 2018, A Clogged Biocontrol Pipeline: Time for a Solution. XV International Symposium on Biological Control of Weeds
12
DISCOVERY OF THREE SPECIES OF SLUG-KILLING NEMATODES IN OREGON AND AN ASSESSMENT OF THEIR LETHALITY TO THE KEY SLUG PEST, DEROCERAS RETICULATUM Colton, AJ.1, Denver, D.R.2, Howe, D.K.2, and Mc Donnell, R.J.1 Department of Crop and Soil Science, Oregon State University, Corvallis OR 97331 Department of Integrative Biology, Oregon State University, Corvallis OR 97331 [email protected]; [email protected]; [email protected]; [email protected]
Nematodes in the genus Phasmarhabditis (Rhabditidae) are lethal parasites of many species of terrestrial slugs and snails, and hence they have important biological control potential. In fact, in Europe, Phasmarhabditis hermaphrodita is currently being used as a commercially available biological control agent (Nemaslug®) to protect a wide range of crops from gastropod damage. The recent discovery of multiple species of Phasmarhabditis in California has resulted in renewed interest in these nematodes as biological control agents of slugs and snails in North America. This provided the incentive for this study, which aimed to 1) Determine if nematodes in the genus Phasmarhabditis are present in Oregon, and if so 2) Assess the lethality of these species and strains to the gray field slug (Deroceras reticulatum) which is the most damaging slug pest in the region. To this end, surveys were completed in a wide range of different cropping systems throughout the state and nematodes recovered from moribund and dead slugs were identified using molecular methods (16S gene). Three species of Phasmarhabditis (P. hermaphrodita, P. papillosa, and P. californica) have been collected from multiple locations throughout Oregon to date. Infectivity trials with these species were completed in the laboratory in 16oz plastic containers containing 25g sterilized, basic topsoil (EarthGro) dampened using 15ml deionized water. Twenty thousand mixed stage nematodes were added to each container and then six Deroceras reticulatum were placed on top of the inoculated soil. Control containers contained no nematodes and all treatment and controls were replicated five times. These trials showed that all three nematode species were lethal to D. reticulatum but the extent of mortality and the speed with which the nematodes cause slug death varied between nematode species. Future research needs for this promising pest control system are highlighted.
13
RODENTICIDE EFFICACY STUDIES WITH CHLOROPHACINEIN AND ZINC PHOSPHIDE IN WASHINGTON STATE HOPYARDS D.B. Walsh Washington State University Irrigated Agriculture Research and Extension Center 24106 N. Bunn Road, Prosser, WA 99350 [email protected]
Severe outbreaks of voles Microtus spp. occurred in hopyards in 2017. Vole feeding girdled hop bines which resulted in the collapse and complete crop loss on injured bines. Damage was clustered in hopyards and harvest was impacted as crews had to make decisions as to whether or not to skip harvesting bines in damaged patches. We speculate that it was the substantial time hop yards had snow cover in the winter of 2017 that contributed to the outbreak of vole populations in Washington State hopyards. This blanket of snow lasted from late December to early March in many locations. Under the snow cover a vole Nirvana was created that stayed warm while simultaneously the snow protected the voles from predation by owls, hawks and cats. When seeking control options we discovered that no rodenticides were registered for use in Washington State hopyards. The Washington State Department of Agriculture issued a 2-yr provisional 24C Special Local Need Registration for zinc phosphide in 2017 and another 2-yr provisional 24C Special Local Need registration for chlorophacinonein in 2018. These provisional 24C registrations required that efficacy studies be completed in order for these two products to be granted full 5-yr 24Cs. We detail herin the data we collected in fall 2018. Voles are mouse like rodents somewhat similar in appearance to pocket gophers. They have a compact, heavy body, short legs, short-furred tail, small eyes, and partially hidden ears. Their long, coarse fur is blackish brown to grayish brown. When fully grown they can measure 5 to 8 inches long, including the tail. Voles are active day and night, year-round. They are normally found in areas with dense vegetation. Voles dig many short, shallow burrows and make underground nests of grass, stems, and leaves. In areas with winter snow, voles will burrow in and through the snow to the surface. Vole populations fluctuate from year to year; under favorable conditions their populations can increase rapidly. In some areas their numbers are cyclical, reaching peak numbers every 3 to 6 years before dropping back to low levels. Voles may breed any time of year, but the peak breeding period is spring. Voles are extremely prolific, with females maturing in 35 to 40 days and having five to ten litters per year. Litter size ranges from three to six. Voles seldom live past 12 months of age. Zinc phosphide is an inorganic compound that combines phosphorus with zinc. When an animal eats the bait, the acid in the animal's stomach turns the zinc phosphide into phosphine. Phosphine is highly toxic and when a sufficient dose is ingested pest rodents die. Chlorophacinone is an anticoagulant rodenticide that has proven effective for over 30 years in various bait formulations against field rodents including: black-tailed prairie dogs, commensal rodents, ground squirrels, pocket gophers, rats and mice, and voles. These anticoagulants require multiple feedings for mortality to occur and off target poisonings of mammals are remedied by ingestion of vitamin K. `Zinc phosphide and diphacinone have registered aerial applications approved in orchard systems in Washington State. Aerial application is not permitted with chlorophacinone. Hop growers are 14
impacted by labor shortages immediately after hop harvest as farm workers are recruited by apple growers to pick apples. Therefore the most efficient way to cover substantial areas with baits is by aerial application. Research plots were established in a hopyard near Moxee, WA on September 18, 2018 immediately after hop harvest was completed. Plots were set out in a randomized complete block design in which in which 8 replicates of 2.25 acre areas were set aside for treatment with either zinc phosphide or chlorophacinone and 8 replicates of 1 acre that remained untreated with a rodenticide. Asphalt roofing shingles were purchased and cut in half to form squares of approximately, 1.25 ft2. Eight of these roof shingles were arbitrarily placed over vole trails to create bait stations in row over residual basal foliage in the hop row per replicate on October 1, 2018. On October 5, 2018 for a pre- treatment assessment of vole abundance apples were sliced (8 slices per apple) in field and skewered on bamboo shish-kebab skewers. These apple slices were the placed under each roof shingle bait stations in the vole trails. These slices were then collected and evaluated on October 11 after 5 days in the field. Approximately 2/3 of the apple slices were gnawed by voles in this pre-treatment assessment (see table below). On October 15, 2018 chlorophacinonein (Rozol®Vole Bait) and zinc phosphide were spread mechanically at a rate of 10 lbs. product per acre. Fresh apple slices were deployed on 19 October as detailed above for a post rodenticide application assessment of the efficacy of the two candidate rodenticides. Analysis of variance was conducted and treatment means were subjected to pairwise t-tests. According to the “gnawed apple index” both chlorophacinonein and zinc phosphide significantly reduced the abundance of voles in the treated areas.
Percent apple slice gnawed ± standard deviation on Active Ingredient Trade name 11-Oct 25-Oct Untreated Untreated 54.69± 9.30 57.81± 13.26a chlorophacinonein Rozol®Vole Bait 71.88± 6.25 9.38± 6.25b zinc phosphide ZP Rodent Bait AG 62.50± 10.21 6.25± 12.50b Treatment means for the gnawed apple index separated by an uncommon letter are significantly (p<0.05) different in pairwise t-tests.
These data will be submitted to the WSDA in anticipation that the full 5-yr Section 24C Special Local Need Registrations will be issued for both zinc phosphide and chlorophacinonein for use as rodenticides in Washington State Hopyards.
15
BROWN MARMORATED STINK BUG NATURAL ENEMIES IN CALIFORNIA D.M. Lightle1, C. Borkent2, V. Popescu2 and C. Pickett2 1UC Cooperative Extension, Glenn County PO Box 697, Orland, CA 95963 2California Department of Food and Agriculture 3294 Meadowview Rd, Sacramento, CA 95832 [email protected], [email protected]
Brown marmorated stink bug (Halyomorpha halys, BMSB) has high potential for damage on numerous California specialty fruit and nut crops (olive, almond, pistachio and peach, among others). This study was undertaken throughout the state of California to understand the native natural enemy complex that may be providing predation and parasitism of BMSB eggs, as well as develop a method for identifying predators from the remains of BMSB egg clusters. In 2017, 729 sentinel egg cards (cardstock containing approximately 28 eggs; figure 1) were placed in 49 sites in California (4 southern, 9 central, 36 northern). In 2018, over 1,000 sentinel egg cards were deployed, including 564 egg cards at 54 locations in northern California. Egg cards were pinned to woody plants (e.g. trunks or tree branches) or attached to the underside of a leaf. Cards remained out for three nights before bringing indoors, imaging, and storing to rear parasitoids. A limited number of sites were equipped with a time-lapse camera which took photos every 5 minutes while the cards were deployed.
Figure 1. Example sentinel egg card with BMSB egg cluster.
In 2017, 26% of the eggs placed on trunks or branches, and 8% of the eggs placed on leaves were consumed by predators. Time lapse photos indicated that the predators include spiders, carabids, ants, earwigs, cockroaches and parasitoids. Damage by predators was more likely to occur to egg masses situated on branches, whereas parasitism was greater when eggs were located on leaves. Predation was most likely to occur during the night. Time-lapse photos also showed that each predator has a distinct feeding “foot-print”, where the type of predator can be identified by the damage left to the egg remains. Predator information will help inform conservation of important natural enemies in both agricultural and urban locations. Low levels of parasitism by native parasitoids continues to underscore the need for release of Trissolcus japonicus to help protect against damage in agricultural production systems in California.
16
BOTRYTIS AND SPOTTED WING DROSOPHILA Gracie Galindo, Caelin Alba, Tara Neill, Walt Mahaffee, Jana Lee USDA-ARS Horticultural Crops Research Unit 3420 NW Orchard Ave., Corvallis, OR 97330 [email protected] , [email protected]
Botrytis cinerea is a fungal pathogen that causes grey mold and affects many different crops in the Pacific Northwest such as blackberries, blueberries, grapes, raspberries, and strawberries. Botrytis spores are often spread by wind or rain and sometimes insects (Holz et al. 2007). The role of insects, like spotted wing drosophila, Drosophila suzukii, in mediating the dispersion of Botrytis is unknown. Drosophila suzukii, is a major insect pest of small fruits in the Pacific Northwest and affects the same fruits as of those infected by Botrytis. While the role of D. suzukii as a vector for Botrytis is unclear, Drosophila melanogaster, a close relative to D. suzukii, is known to carry Botrytis spores on its external cuticle and can release spores after passage through its digestive track (Louis et al. 1996). Subsequent interaction between D. melanogaster and fruit may result in transfer of spores. To determine if similar mechanisms of transmission of Botrytis are facilitated by D. suzukii we investigated 1) if D. suzukii can carry Botrytis spores and 2) if they can transfer Botrytis spores from one fruit to another fruit resulting in Botrytis infection.
Methods Drosophila suzukii used in experiments were from laboratory colony started from wild flies collected from infested fruits and reared on autoclaved diet with no living yeast.
Question 1: Does D. suzukii carry Botrytis spores? To assess if D. suzukii are capable of carrying Botrytis spores, choice and no-choice assays were conducted on blueberries inoculated with GFP-Botrytis cinerea (fluoresces green under UV light). For choice assays, 12 (6♀: 6♂) adult D. suzukii (7 days old) were placed in a petri dish (25 x 90 mm) that contained one infected GFP-B. cinerea blueberry, during the sporulation phase, on one side of the dish and one uninfected blueberry on the other side. For no-choice assays, 12 (6♀: 6♂) adult D. suzukii (7 days old) were placed in a petri dish (25 x 90 mm) that contained one infected GFP-B. cinerea blueberry. After flies were exposed for 24 hours, they were individually transferred, using aseptic technique, into 24-well plates containing either a selective media (Potato Dextrose Agar ½ strength with Hygromycin 75µl/ml) or a non-selective media (Potato Dextrose Agar ½ strength). Flies were allowed to walk on media for 24 hours and were then individually removed from the well plates (Figure 1). The plates were incubated at 21°C and were monitored for Botrytis growth for one week. Six replicates were conducted on selective media for choice and no-choice assays and seven replicates were conducted on non-selective media for both choice and no-choice assays. Botrytis growth was assessed by recording the percent area of florescence observed in each individual well.
Figure 1. Diagram of experimental design for no-choice and choice assays.
17
Question 2: Does D. suzukii transfer Botrytis to berries? To assess transfer of Botrytis to berries, 12 (6♀: 6♂) adult D. suzukii (5 to 8 days old) were placed in a petri dish (25 x 90 mm) that contained one infected Botrytis cinerea blueberry (mixed with four strains 250, 251, Ger 1, and Ipm) and exposed for 24 hours. Flies were then individually transferred, using aseptic technique, into sterile treatment arenas (25 x 90 mm petri dishes). Treatments included 1) intact blueberry + ♀, 2) intact blueberry + ♂, 3) control intact (no flies) blueberry, 4) wounded blueberry + ♀, 5) wounded blueberry + ♂, and 6) control wounded (no flies) blueberry. All berries used were initially disinfected by soaking them in a 7.3% bleach solution for 5 minutes and were then rinsed with sterile DI water. Blueberries were wounded by inserting a sterile probe completely through each berry twice. Flies were allowed to walk around the treatment arenas for 24 hours at room temperature. After 24 hours, flies were individually removed, using aseptic technique, from treatment arenas (Figure 2). To provide treatment arenas with moisture, sterile DI water was added onto a small piece of sterile filter paper every other day until the last day of observations. Berries were monitored for 11 days after files were removed from treatment arenas, and Botrytis growth was assessed by recording if Botrytis was present and the percent area of Botrytis covering berry surface. A total of eight trials were conducted, each containing three replicates for each treatment condition (a total of 24 replicates per treatment).
Figure 2. Diagram of Botrytis transfer assays.
Statistics No statistics were run on Question 1 which confirmed GFP-Botrytis transfer to agar media. For Question 2, all data were first included to test if fly presence led to Botrytis development on clean berries by Chi-square analysis. Subsequent analyses excluded ‘no fly’ control treatments to test whether wounding status (wounded/ intact), fly sex (female/ male), or the four combinations (intact+♀, intact+♂, wounded+♀, wounded+♂) led to Botrytis infection by additional Chi-square
18
tests. Next, the proportion of the berry surface covered with Botrytis was compared among all data with fly presence as the effect variable, trial as a random effect on proportion coverage as the dependent variable. Subsequent analysis excluded ‘no fly’ treatments to test wounding status, fly sex or the interaction as effect variables, and trial as a random effect in a linear mixed model, with post- hoc means comparisons by Tukey HSD. Lastly, uninfected berries were excluded from the dataset, and coverage was compared among only ‘Botrytis-positive’ berries between wounded/ intact berries in a similar model. All analysis were done in JMP 14.0.
Results Question 1: Does D. suzukii carry Botrytis spores? GPF-Botrytis was positive in all transfers on selective and non-selective media. On selective media, both choice (n=72) and no-choice (n=72) tests had an average of 100% area of florescence. On non- selective media, choice tests (n=84) had an average of 53.3% area of florescence while no-choice (n=84) tests had an average of 56.3% area of florescence.
Question 2: Does D. suzukii transfer Botrytis to berries? Fly presence had an effect on Botrytis transfer (presence/ absence). The rate of Botrytis infection was significantly higher (~53%) in blueberries that were exposed to either female and male D. suzukii while 10.4% of control berries (berries with no flies) developed Botrytis, suggesting some background contamination (χ2 = 27.7, P = <0.0001; Figure 3-1st section).
To examine potential differences in transfer between wounding status of berries and between males and females, ‘no fly’ control treatments were excluded from subsequent analyses. The incidence of Botrytis in wounded blueberries (68.8%) was significantly higher than intact blueberries (37.5%), suggesting that wounded berries are more susceptible to Botrytis infection (χ2= 9.6, P = 0.002; Figure 3-2nd section). When all berries with flies are considered, there were no differences between males and females for Botrytis transfer (χ2 = 0.042, P = 0.84; Figure 3-1st section). However, differences in transfer incidence are highest among males with wounded berries when all four groups are compared to each other (χ2 = 10.8, P = 0.013; Figure 3-3rd section).
19
The presence of flies also had an effect on percent of berry surface covered with Botrytis. The percent area of Botrytis covering blueberry surface was greater in berries exposed to males (18.9%) and females (12.1%) compared to blueberries without flies (4.3%; Fly presence F1,135= 6.6, P = 0.012; Figure 4-1st section).
Once again, ‘no fly’ control treatments were excluded from subsequent analyses to examine differences in Botrytis coverage between wounding status of berries and between males and females. Botrytis coverage was significantly higher in wounded blueberries (22.7%) than intact blueberries nd (8.4%; F1,85 = 6.6, P = 0.012; Figure 4-2 section). However, this could be related to the fact that wounded berries had more infected berries. When only Botrytis-infected berries are considered, wounded and intact berries had similar surface coverage, 33% ±6 and 22% ±8 (F1,43 = 0.85, P = 0.36, trial as a random effect). Neither sex (F1,85 = 1.5, P = 0.22) nor the interaction between sex and wounding (F1,85 = 0.18, P = 0.67) resulted in significant differences in surface coverage.
Summary Based on observations made in these studies, Drosophila suzukii are physically capable of vectoring spores of Botrytis. However, these studies were conducted in petri dishes in a laboratory and doesn’t necessarily reflect field conditions. Therefore, future work should determine the extent to which D. suzukii contributes to the dispersal and economical damage of Botrytis in agricultural settings. Thus far, males and females appear to transfer Botrytis similarly to blueberries in controlled conditions. Initially, we thought that the ovipositional activity of females may encourage infection, or hinder infection if females transfer other competitive microorganisms during oviposition.
References Holz, G., S. Coertze, and B. Williamson (2007) The ecology of Botrytis on plant surfaces. In Y. Elad, B. Williamson, P. Tudzynski and N. Delen (eds.), Botrytis: Biology, Pathology and Control. Springer, Netherlands.
Louis C, Girard M, Kuhl G, Lopez-Ferber M (1996) Persistence of Botrytis cinerea in its vector Drosophila melanogaster. Phytopathology 86:934-939 Section I: Invasive and Emerging Pests (Poster Presentation)
20
HELPING OUT THE SAMURAI WASP J. C. Lee, Hanna McIntosh, Gracie Galindo USDA-ARS Horticultural Crops Research Unit 3420 NW Orchard Ave., Corvallis, OR 97330 [email protected] , [email protected] , [email protected]
The brown marmorated stink bug (BMSB), Halyomorpha halys, is a serious polyphagous pest and a nuisance in our homes. Unfortunately, these large-bodied pests are difficult to manage with insecticides due to their long legs and thick exoskeleton. Biological control with the Samurai wasp, Trissolcus japonicus, can potentially reduce pest populations. To use T. japonicus more effectively, we need to improve our ability to mass rear them, and find ways to enhance their survival in the field. First, we examined frozen and variable-aged BMSB egg masses for rearing T. japonicus, since many labs are constrained by the number of fresh eggs available year around. We found that frozen eggs are suitable for T. japonicus development, but had lower overall parasitism rates than fresh eggs. Parasitism rate continued to decrease the longer frozen eggs were stored in the freezer. BMSB eggs collected within 3 days of laying were equivalent to <1 d old eggs and showed no reduction in parasitism. We conclude that frozen and <3 d old eggs can be used supplementally in rearing when availability of fresh, newly-laid eggs is low, but we advise against complete replacement of fresh eggs. Second, we assessed possible floral resources for T. japonicus by testing longevity when provided marigold, sweet alyssum, or buckwheat in the laboratory. Survival of wasps fed buckwheat was equivalent to those fed honey (positive control), and increased survival compared to wasps fed only water (negative control). Next, we conducted nutrient profile bioassays to determine how each flower impacts the lipid, glycogen, and sugar levels of wasps. Lipid and glycogen levels were the same for all treatments, but buckwheat increased sugar levels equivalent to honey (positive control). We conclude that buckwheat provides a suitable floral resource for T. japonicus, likely by providing critical sugars to the wasp.
Note: The first project is in review at the journal Biocontrol Science and Technology by McIntosh et al.
21
ACUTE TOXICITY OF ESSENTIAL OILS TO ADULTS OF THE PEST SLUG DEROCERAS RETICULATUM IN LABORATORY AND GREENHOUSE BIOASSAYS M. L. Klein, T. Chastain, R. J. Mc Donnell Department of Crop and Soil Science, Oregon State University 3050 SW Campus Way, Corvallis, OR 97331 [email protected], [email protected], [email protected]
Terrestrial slugs are a successful group of organisms that are distributed throughout the world, in many cases, becoming established crop pests. In Oregon, the gray field slug, Deroceras reticulatum is of primary concern due to it feeding on key arable crops in the region including annual ryegrass, perennial ryegrass, tall fescue, and white clover. The slug has become ubiquitous in the Willamette Valley, thriving in the region’s cool, rainy climate, similar to that of its native range in Western Europe. In crops grown in the Willamette Valley, the loss of field burning as a control method, and an increase in no-till production have led to increased slug damage and in turn encouraged growers to become more reliant on a limited selection of chemical controls. The most prevalent active ingredients: metaldehyde and iron phosphate however, typically only elicit a 10 to 60 % mortality rate, leading to an increased interest in new and effective chemical controls. To date there has been minimal progress made on developing novel molluscicides. However, over the past 20 years, essential oils, a diverse group of plant-derived distillates, have proven effective at controlling various insects, mites, fungi, and nematodes and are becoming more prominent as a means of controlling mollusks. Essential oil toxicity towards the terrestrial pest snail Cornu aspersum, and several species of marine and aquatic mollusks has been demonstrated, however, their effectiveness against terrestrial slugs has not been determined. In this study, gray field slugs were exposed to one of thirteen different essential oil solutions in concentrations between 0.05 % and 1 % in order to determine the Lethal Concentration 50 (LC50) of each oil. Thyme and spearmint were most lethal to slugs with LC50 values of 0.148 % and 0.153 % respectively. The two most toxic treatments were then tested in a greenhouse microcosm setting to simulate field conditions. Microcosms were planted with annual ryegrass, inoculated with slugs, and treated with a spray of double the LC99. Both thyme and spearmint treatments were 97.5 % lethal. In a separate greenhouse bioassay, seedlings of two cultivars of perennial ryegrass and two cultivars of tall fescue were directly sprayed with either thyme or spearmint oil at concentrations of 0.25 % and 0.5 %. Phytotoxicity was assessed by eye, with a chlorophyll meter, and by taking dry weight of plants at 6 and 17 days after treatment. No signs of phytotoxicity or differences in growth were detected. Although essential oils are more expensive than conventional chemical controls (e.g. Slug- Fest All Weather Formula), they can cause rapid mortality, are non-toxic to humans, and are exempt from pesticide registration and residue tolerance requirements. Thyme and spearmint oil could be used in certified organic operations or in rotation with conventional chemicals when other modes of action are needed. Also, specific constituent molecules could be isolated and tested for their efficacy against slugs, potentially lowering costs.
22
RNAi TECHNOLOGY: CURRENT STATUS AS AN ALTERNATIVE PEST MANAGEMENT TOOL TO CONTROL SPOTTED WING DROSOPHILA S.-J. Ahn1,2, K.M. Donahue1, M.-Y. Choi1 1USDA-ARS Horticultural Crops Research Unit, 3420 NW Orchard Ave., Corvallis, OR 97330 2Department of Crop and Soil Science, Oregon State University, 3050 SW Campus Way, Corvallis, OR 97331 [email protected], [email protected] RNA interference (RNAi) is a post-transcriptional gene silencing mechanism that is initiated by the presence of double-stranded RNA (dsRNA), resulting in degradation of a target messenger RNA (mRNA) and failure of the corresponding protein production. RNAi by dsRNA has been exploited for various applications, like investigation of gene function by gene-specific knockdown. Gene suppression via RNAi also provides an alternative strategy for insect pest management. Recently, EPA approved the first RNAi product developed by Monsanto, a genetically modified corn, to control the western corn rootworm. Although RNAi technology is a promising tool for insect pest management, the efficacy of RNAi varies among different insect orders and also depends on various factors. Among others, three major challenges in RNAi for insect pest management are: (1) identifying suitable target genes, (2) providing cost-effective dsRNA production, and (3) developing optimal dsRNA delivery into the target pest. The spotted wing drosophila (SWD), Drosophila suzukii, a serious invasive pest damaging a broad range of small fruits in U.S, has rarely been investigated for RNAi. Here we applied the RNAi technology against SWD to address the major challenges above. First, we screened 32 different genes for the RNAi to SWD by injecting dsRNA into the SWD adult. Target genes included housekeeping genes, neurohormone genes and receptor genes. Results showed various mortality among different target genes to SWD adult. The most effective three target genes were selected for further study. It was confirmed that the three candidate genes were significantly suppressed in their gene expression (mRNA level) by dsRNA injection. Second, we developed a cost-effective dsRNA production using a bacterial expression system. The dsRNA-template DNA fragment was inserted in the special expression vector (L4440), which was then transformed into the dsRNA degradation enzyme-deficient E. coli strain (HT115). After induction of RNA transcription, and the dsRNA produced was extracted and quantified. As a result, a considerable amount of dsRNA, 19.5 µg per ml, was produced by liquid culture and the purification process was also simplified using sonication method. The delivery of dsRNA is the next challenge to be addressed. The most applicable option is to let the adults to feed dsRNA. We tested the stability of dsRNA in the gut by incubating dsRNA with the gut homogenates. Interestingly, dsRNA was degraded when it was mixed with the midgut homogenate, not with the foregut homogenate, suggesting the dsRNA-degradation enzyme might be active in the fly’s gut. More research is required to circumvent this gut barrier for the effective and field-applicable RNAi technology to manage SWD.
23
Figure 1. Mortality of the SWD adults after injection of different dsRNAs. Adult flies were injected with 1 µg of dsRNA delivered in 50 mL water, and the mortality measured after 24 h. GFP (green fluorescence protein) dsRNA was used as a control.
Figure 2. Schematic diagram of the bacterially-expressed dsRNA production system. (A) The target gene fragment is inserted in the multi-cloning site in the expression vector (L4440), which is then transformed into the RNase III-deficient E. coli strain HT115 (DE3). IPTG induces RNA transcription, and the dsRNA produced is purified. (B) The target dsRNA isolated from bacterial culture were analyzed by agarose gel by electrophoresis. White arrows indicate dsRNAs. M: DNA marker.
24
Figure 3. Degradation of dsRNA by midgut homogenate of SWD adult. (A) The gut structure of SWD adult is composed of foregut (including crop), midgut, and hindgut. (B) Gel electrophoresis after incubation of dsRNA at 37 °C for 30 min with different treatments: 1, dsRNA only (control); 2, gut homogenate only (control); 3, dsRNA + RNaseIII (positive control); 4, dsRNA + gut homogenate (10 gut equivalent); 5, dsRNA + gut homogenate (5 gut equivalent); 6, dsRNA + gut homogenate (1 gut equivalent); 7, dsRNA + gut homogenate (0.5 gut equivalent).
25
Testing compatibility of a biocontrol agent of Halyomorpha halys with pest management regimes in Pacific Northwest hazelnuts
Tatum Marie, David Lowenstein, Erica Rudolph, Anthony Mugica, Heather Andrews, and Nik Wiman Oregon State University, North Willamette Research and Extension Center, Aurora, OR
Oregon is responsible for 99% of the US hazelnut crop, and production has entered a new phase of expansion enabled by new disease resistant varieties. Historically, filbertworm, Cydia latiferreana (Walsingham), a native tortricid moth, has been the key direct pest of hazelnuts. Conventional growers normally make one to two applications of a pyrethroid spray (Asana), while organic growers rely heavily on applications of spinosad (Entrust). The invasion of the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), has meant that PNW hazelnut growers have yet another direct insect pest to contend with. This insect feeds on hazelnuts and can damage the kernel by feeding through the shell. Unfortunately, the most effective insecticides for this insect greatly disrupt integrated pest management regimes in crops, which could mean additional applications of pyrethroids will be required to keep damage in check. Such management practices would increase the possibility of secondary pest issues, and otherwise disrupt the current IPM system. Hazelnut insecticide use is minimal compared to tree fruits and other perennial crops and there is a high reliance on biological control, particularly for aphids and leafrollers. The samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), is a highly effective egg parasitoid of H. halys, and has been shown to exhibit a 75% parasitization rate in its native range in Asia. This wasp was found in Portland in 2016, most likely following adventive introduction. Since then, our team has redistributed T. japonicus around OR in locations that have high populations of H. halys and specialty crop production, in an attempt to help the wasp become established and limit the impact of the stink bug on high-value crops. As the parasitoid establishes across the state of OR, this research was intended to help us determine if biocontrol will be compatible with pest management practices. We evaluated wasp mortality when exposed to insecticides registered for use against C. latiferreana in hazelnuts. In the summer of 2018 mesh clip cages containing five to seven T. japonicus were hung in trees prior to being treated with insecticides. Cages were removed from trees 24 hours after applications were made, and wasps were assessed for mortality several weeks following deployment. Wasps exposed to the diamaide insecticide Altacor survived longer than wasps treated with all other insecticides. Altacor is an insecticide which targets lepidopteran pests, and based on our results, could be compatible with biocontrol agents such as T. japonicus. In a study that coincided with our T. japonicus mortality assessment, we found that C. latiferreana damage was significantly reduced when trees were treated with Altacor.
26
While it does appear that some insecticides that are effective against C. latiferreana could be compatible with biocontrol of H. halys, it is more likely that T. japonicus will be better able to control H. halys in areas outside of managed crops. T. japonicus is thought to prefer to forage among understory plants in forest habits, which tend to surround many crops grown in western OR, including hazelnut orchards. This means that there is a high likelihood that T. japonicus could become established in habitats surrounding hazelnut orchards, and prevent or reduce H. halys from immigrating into the crop.
27
SECTION II Bees and Pollinators
28
THE OMICS APPROACH TO HONEY BEE NUTRITION Priyadarshini Chakrabarti1*, Jeffrey T. Morré2, Liping Yang2, Claudia S. Maier2,3 and Ramesh R. Sagili1
1 Department of Horticulture, Oregon State University, Corvallis, OR 97331, USA 2 Department of Chemistry, Oregon State University, Corvallis, OR 97331, USA 3 Linus Pauling Institute, Oregon State University, Corvallis, OR 97331, USA
[email protected], [email protected], [email protected], [email protected], [email protected]
Introduction Poor nutrition is one among the suite of factors cited as probable causes for honey bee colony declines over the past decade. Habitat loss, monocultures, and changes in plant flowering phenology are believed to be largely contributing to poor nutrition1-4. Pollen and nectar are the two principal food resources (macronutrients) for honey bees. Carbohydrate-rich nectar supplies bees with energy, while pollen serves as the primary source of proteins, lipids, and vitamins5-6. Research on honey bee nutrition is still an underdeveloped area7-8 even though bee nutrition has been studied for a significant amount of time. Honey bee nutrition has largely focused on understanding the requirements for carbohydrates and proteins and research on the needs of phytosterols in bees is still needed. Like macronutrients, micronutrients also play an important role in honey bee nutrition. Sterols, an important micronutrient, play a vital role in insect physiology. Sterols are precursors for molting hormones, act as signaling molecules affecting development and are critical for cell membrane development and function9-10. Honey bees like all insects, are sterol auxotrophs being unable to synthesize sterols and hence depend on dietary sources for the sterols10. Honey bee colonies used for crop pollination often endure nutritional stress due to the quality or quantity of pollen forage available to them in such agricultural landscapes is inadequate2. Beekeepers feed artificial protein supplements to their colonies during periods of nutritional dearth. However, protein supplements which lack 24-methylenecholesterol, a critical phytosterol, are unable to sustain long term brood rearing in those colonies. Hence, there is an urgent need to understand the phytosterol composition of major bee forage pollens and other bee dietary sources. There is also a need to holistically look at the other nutritional composition of various bee diets. Mass spectrometric analytical approach has the potential to assist in critical nutritional evaluations and studies pertaining to honey bee nutrition. Our study discusses the results and insights gained based on this mass spectrometric techniques.
29
Results and Discussion The study has approached bee nutrition from three different perspectives. We applied mass spectrometry methods to study proteomics, metabolomics and targeted lipidomics (phytosterol analysis). Honey bees treated with 0.5% 24-methylenecholesterol in their diets demonstrate significant changes in their proteome profiles. The proteomics study involved the label free quantification of the proteome of honey bee heads measured at the Oregon State University’s Mass Spectrometry Center (OSUMSC). A total of 2057 proteins with high confidence were identified from honey bee samples. Relative quantitative proteomic analysis indicated that the expression of interested proteins exhibited significant differences between groups treated with sterol diets and the control group. Important proteins, like major royal jelly protein 1, fatty acid binding protein, oxysterol binding protein and vitellogenin changed in abundance with varying dietary sterol concentrations. Metabolomics studies at the OSUMSC helps to further understand the differential nutritional framework of various honey bee dietary sources – pollens, vegetable oils and commercial diets. Metabolites were separated on an Inertsil Phenyl-3 stationary phase (GL Sciences) coupled to a quadrupole-time-of-flight mass spectrometer (Triple TOF 5600, AB SCIEX) with MS/MS spectra recorded using Information Dependent Acquisition-Mass Spectrometry (IDA-MS). Metabolites have been identified using the OSU-IROA in-house metabolite library. LC-Atmospheric Pressure Chemical Ionization-Multiple Reaction Monitoring (LC-APCI-MRM) were established and standardized at the OSUMSC for the quantification of 12 different phytosterols. Each of the sample types differed in their sterol composition. The concentration of our phytosterol of interest, 24-methylenecholesterol, was found to be 3490±74 ppm, 662±73 ppm and 110±10 ppm in corbicular almond pollen, honey bee tissues and borage oil respectively. However, 24-methylenecholesterol was not detected in the commercial diet sample. It is crucial to evaluate the nutritional composition of various honey bee diets holistically. The knowledge gained by understanding phytosterol composition and other important metabolites in various crop and non-crop pollens could be used by beekeepers (by selecting appropriate pollen substitutes) and land managers/conservation groups to improve bee nutrition. This will benefit bees dependent on pollen for their growth and survival. This research is also important to understand the physiological underpinnings of nutrients (sterols for example) on honey bee physiology and lays the foundations for future research on identifying key protein markers vis-à-vis nutritional stress. References 1. Kremen, C., Williams, N. M. & Thorp, R. W. Crop pollination from native bees at risk from agricultural intensification. Proc. Natl. Acad. Sci. 99, 16812–16816 (2002). 2. Naug, D. Nutritional stress due to habitat loss may explain recent honeybee colony collapses. Biol. Conserv. 142, 2369–2372 (2009). 3. Vanbergen, A. J. et al. Threats to an ecosystem service: pressures on pollinators. Front. Ecol. Environ. 11, 251–259 (2013). 4. Otto, C. R. V., Roth, C. L., Carlson, B. L. & Smart, M. D. Land-use change reduces habitat suitability for supporting managed honey bee colonies in the Northern Great Plains. Proc. Natl. Acad. Sci. 113, 10430–10435 (2016). 30
5. Brodschneider, R. & Crailsheim, K. Nutrition and health in honey bees. Apidologie 41, 278- 294 (2010). 6. Winston, M. L. The biology of the honey bee (Harvard University Press, Cambridge, 1987). 7. Somerville, D. Fat Bees Skinny Bees: - a manual on honey bee nutrition for beekeepers. Rural Industries Research and Development Corporation. NSW Dept. Primary Industries (Goulburn, NSW, Australia, ISBN 1 74151 1526, 2005). 8. Bonoan, R. E., O’Connor, L. D. & Starks, P. T. Seasonality of honey bee (Apis mellifera) micronutrient supplementation and environmental limitation. J. Insect Physiol. 107, 23–28 (2018). 9. Behmer, S. T. & Nes, W. D. Insect Sterol Nutrition and Physiology: A Global Overview. Adv. In Insect Phys. DOI: 10.1016/S0065-2806(03)31001-X (2003). 10. Carvalho, M. et al. Survival strategies of a sterol auxotroph. Development 137, 3675-3685 (2010).
31
SECTION III Environmental Toxicology and Regulatory Issues
32
Insecticide/Miticide/Fungicide Decline in PNW Caneberries Bev Gerdeman, Joe DeFrancesco, Camille Holladay and Hollis Spitler [email protected], [email protected], [email protected], [email protected]
Spotted wing drosophila, Drosophila suzukii, is the primary direct pest of caneberry fruit. Weekly insecticide applications that are necessary to protect berries may put growers at risk for pesticide residue violations in overseas markets. 2018 was the 2nd year of a 3-year study to evaluate insecticide, miticide and fungicide degradation curves for the PNW region. Field trials were conducted in Lynden, WA (raspberry), and Aurora, OR (raspberry and blackberry). All treatments were replicated four times with an over-the-row boom at the Washington site, and with a backpack sprayer at the Oregon site. Residue analysis was performed by Synergistic Pesticide Lab in Portland, OR. Target export countries include Australia (AU), Canada (CA), China (CH), European Union (EU), Hong Kong (HK) Japan (JA), Korea (KO) and Taiwan (TA). Maximum Residue Levels (MRLs) or tolerances, based on the “www.globalmrl.com” database, are current as of 12/01/2018. Fifteen insecticide/miticides and 14 fungicides were included in the study (Table 1). Luna Tranquility, Pristine, Tanos and Switch are combo treatments requiring decline studies on both products. Products are divided into 2 treatments each for insecticides/miticides and 2 for fungicides to reduce the chances of incompatibility. No buffers were added.
Table 1. 2018 Caneberry Decline Study Rate USA PHI Active ingredient Product IRAC Rate (product/A) (lb ai/A) (days) Treatment #1 (T1) Tank Mix bifenazate Acramite 50WS 25 0.5 16 oz. 1 bifenthrin Brigade 2EC 3A 0.1 6.4 fl. oz. 3 fenbutatin (hexakis) Vendex 50W 12B 1 32 oz. 3 hexythiazox Savey DF 10A 0.1875 24.0 fl. oz. 3 imidacloprid Admire Pro 4A 0.1 2.8 fl. oz. 3 methoxyfenozide Intrepid 18A 0.25 16 fl. oz. 3 spinetoram Delegate WG 5 0.09 6.0 oz. 1 flupyridifurone Sivanto Prime 4D 0.18 14 fl oz 0 Treatment #2 (T2) Tank Mix acequinocyl Kanemite 15SC 20B 0.3 31 fl. oz. 1 cyantraniliprole Exirel ** 28 0.133 20.5 fl. oz. 3 fenpropathrin Danitol 2.4EC 3A 0.3 16.0 fl. oz. 3 malathion Malathion 8F 1B 2 32.0 fl. oz. 1 spinosad Success 5 0.09 6.0 fl. oz. 1 thiamethoxam Actara 4A 0.047 3.0 oz. 3 zeta-cypermethrin Mustang MAXX 3A 0.025 4.0 fl. oz. 1
Rate USA PHI Active Ingredient Product FRAC Rate (product/A) (lb. a.i./A (days) Treatment # 3 (T3) Tank Mix Azoxystrobin Abound 11 0.25 15.5 fl. oz. 0 Captan Captan 4L M04 2 64 fl. oz. 3 Fenhexamid Elevate 17 0.75 24 oz.. 0 Fluopyram + pyrimethanil Luna Tranq 7 & 9 0.9 27 fl. oz. 0 0.075 Rasp = 3 oz. Myclobutanil Rally 3 0 0.125 Black = 5 oz. Penthiopyrad** Fontelis 200 7 0.313 24 fl. oz. 0 Polyoxin-D Ph-D 19 0.044 6.2 oz. 0 Treatment # 4 (T4) Tank mix Boscalid + pyraclostrobin Pristine 7 & 11 0.55 23 fl. oz. 0 Cymoxanil + famoxadone Tanos 27 & 11 0.31 10 oz. 0 Cyprodinil + fludioxonil Switch 9 & 12 0.55 14 oz. 0 Iprodione Rovral 2 1 32 fl. oz. 0 Isofetamid Kenja 7 0.4 15.5 fl. oz. 7 Pydiflumetofen** ??? 7 0.134 10.3 fl. oz. 0 Pyriofenone Prolivo 300 SC 50 0.098 5 fl. oz. 0 ** not currently registered in caneberries, *** new formulation not yet registered in caneberries 33
Residue Declines of Select Active Ingredients The MRL for cyantraniliprole for caneberries was established by the EPA in November 2018; however, it is not yet registered. Registration is expected by the 2019 field season at which time a 1- day PHI is expected. The decline patterns below (Fig. 1) indicate the residue at 1-day PHI is well below the US tolerance set at 4.0 ppm for both raspberries and blackberries, however this is a relatively new chemistry and MRLs have not been established in many other countries, as reflected by the “no tolerance” status in TW and CH, or by low tolerances as seen in EU (0.9 ppm), KO (0.7), CA (0.1), AU (0.05) and JA (0.01). Nevertheless, this year’s decline study suggests residues drop below 0.9 ppm sometime between 1 and 3 days with some fluctuations, and below 0.7 ppm between 5 and 7 days for raspberries and 7 and 10 days for blackberries. A third year is definitely needed to provide more confident decline curves.
Fig. 1. Cyantraniliprole decline 2018 caneberries.
2018 represents the first year of results for acequinocyl (Kanemite) (Fig. 2). The US tolerance is 4.0 ppm; the graph indicates the residue level was well below that at 1-Day PHI. Although the residues declined quickly, the tolerance is not very compatible with those of major trading partners including no tolerance set for AU, CH, HK and JA. The EU and TA tolerances are set at 0.01 but residues remain at 0.05 beyond 21 days.
Fig. 2. Acequinocyl decline 2018 caneberries.
34
2018 is also the first year we collected residue data for pyriofenone (Prolivo) (Fig. 3). The US tolerance is 0.9 ppm at 1-Day PHI. By 1-Day PHI, residues were all below 0.74 ppm and dropped steadily afterwards, similar to the curve exhibited by OSU blackberries. Only CA (0.9 ppm) and KO (2 ppm) have similar or higher MRLs than the US. The remaining countries either have no established MRL (CH, HK and TA) or it is set very low (EU and JA at 0.01 ppm, and AU at 0.05). Residues finally fall within this range but very late, somewhere between 14 (0.1 ppm) and 21 days (0.04). Additional decline studies are needed to verify these curves.
Fig. 3. Pyriofenone decline 2018 caneberries.
2018 was the first year for fenbutatin oxide (Vendex) to be included in the residue decline study (Fig. 4). Vendex is an older miticide, first registered in the US in 1974, and is not registered on blackberry. Residues at 3-day PHI were well below the US tolerance (10 ppm) and below the MRLs in the EU (5 ppm) and KO (3.0 ppm); but declines fluctuated at two of the sites, a warning that at least two more years will be required to provide reliable curves. Residue levels were above 1.0 ppm even after 16 days, which would not be acceptable in AU; residue levels did not meet Taiwan’s MRL of 0.01 ppm even after 21 days.
Fig. 4. Fenbutatin oxide decline 2018 caneberries.
35
Sivanto Prime, flupyradifurone, was added to the residue study in 2018. All residues fell well below the US tolerance set at 5 ppm at 1-Day PHI. This is a fairly new insecticide and the MRLs set by the trading partners reflect this. No tolerance is assigned to AU, CH and HK while the EU and KO (1.5 ppm) tolerances were close to the 1-day PHI of 1.4 ppm. Japan’s tolerance (0.01ppm) is not attainable even beyond 21 days.
These results are preliminary, particularly those represented here for the first time. Decline studies require at least three years to provide reliable trends due to the inherent fluctuations between sites, including differences in plant age, application equipment and weather.
36
SECTION IV Field Crop Pests
37
QUANTIFYING ACARICIDE RESISTANCE STATUS IN SEVERAL CALIFORNIA BERRY PLANTATIONs TETRANYCUS URTICAE POPULATIONS TO BIFENAZATE, HEXYTHIOZOX, AND ABAMECTIN. A. Adesanya and D. Walsh Department of Entomology, Washington State University
Populations of two-spotted spider mites Tetranychus urticae collected from conventional and organic berry plantations in several growing districts of California were subjected to dose mortality bioassay tests for the commonly used acaricides abamectin, bifenazate, and hexythiazox. The growing districts included Oxnard, Watsonville, Elkhorn Slough, and Salinas. Six mite populations were collected from strawberries. One population was collected from a plantation of organic blackberries in Watsonville, one population was from a conventional raspberry plantation near Oxnard and one population was from a conventional raspberry field near Oxnard. Three of the populations were collected from strawberry fields being produced organically and three were from strawberry fields being produced under conventional practices. These data present a snapshot of the resistance status of these populations at these specific locations for when the mites were collected on March 5, 2018. Mites when received at WSU were transferred and held in colony on bean plants. The mites were sorted and all other mite species beside the two spotted mite Tetranychus urticae Koch (Acari:Tetranychidae) were eliminated from our newly established colonies. All of the results detailed specifically were conducted on T. urticae. We have conducted similar research for several years now in Washington State, primarily on mites in hopyards but additionally in peppermint and silage corn and alfalfa seed fields. The outcome of the dose-response bioassays for bifenazate, hexythiazox, and abamectin are presented in the figures and tables below. T. urticae populations from organic farms were generally more sensitive to the three tested acaricides compared to mite populations collected from conventional farms. With abamectin and bifenazate we subjected adult gravid female T. urticae to serial dilutions of these acaricides in bioassay arenas that consist of leaf disks with 10 mites transferred onto each leaf disk. The mites on the leaf disks are sprayed in our Potter™ precision spray tower and evaluated for mortality roughly 24 hrs after treatment. The mites are considered “dead” if they fail to move less than their body length when prodded by a small camel-hair brush. For mite growth inhibiting (ovicidal) acaricides like hexythiozox, we create our leaf disk arenas and populate the leaf disks with gravid adult females. We permit the female mites to lay eggs for 24 hrs and then we remove them. We count the number of eggs present on each leaf disk and then spray the eggs on the leaf disk bioassay arenas in our Potter spray tower. Mortality is assessed by failure of the eggs to hatch between 4 and 5 days after treatment. Mite eggs are most susceptible to poisoning when they are newly laid and tolerance increases as eggs mature. Most untreated eggs will hatch within 4 and 5 days at room temperature in the laboratory. In both bioassay methods mortality is corrected for control (untreated with acaricides) mortality by Abbot’s formula. We develop resistance ratios (RR) by dividing the lethal concentration of the acaricide being tested that is required to kill to kill 50% of the candidate population (LC50) divided by the LC50 of 38
our acaricide naïve laboratory population. Our susceptible lab colony was field collected from volunteer grape vines in Montana over 10 years ago. It has been maintained in colony and exposed to no poisons since. Hence we call this population our “acaricide naïve population”. We conclude that if RRs are less than 10 (10
resistant (RR>100) and the other 6 populations to be moderately resistant (10>RR<100). Obviously resistance to hexythiozox is widespread among the California berry growing districts.
Table 2. Toxicity of Hexythiazox(Savey) to T. urticae populations collected from Strawberry plots in California Population % N Slope±S LC50(95% RR50 LC90(95% RR9 χ² (df) a Mort E CI) CI) 0 Susceptible, 100 65 0.87±0.0 2.2(1.0-4.5) 1 64.7(24.5- 1 71.6(13 WA 6 9 395.7) ) Oxnard 1 48.7 31 0.5±0.1 1190(399.7- 541 >> >> 3.8(10) Conv SB 5 13465) Oxnard 2 82.8 28 0.5±0.1 43.1(15.9- 19.6 11257(2053- 174 13.3(10 Organic SB 3 127) 59791) ) Oxnard 3 83.4 30 0.9±0.12 64.8(37- 29.5 2029(856- 31.4 8.4(10) Organic SB 1 111) 8352) Oxnard 4 64.1 29 0.6±0.1 189.1(93- 86 42325(6884- 654. 7.4(10) Conv RB 6 532) 173481) 2 Salinas 1 77.6 23 0.7±0.13 829(425- 376.8 4207(1308- 65 3.4(10) Conv SB 6 1674) 38157) Wat 1 Organic SB Wat 2 84.9 25 0.7±0.1 43.7(22.6- 19.9 3335.8(1013. 51.6 7.7(10) Organic BB 0 84.7) 8-29929) Elkhorn 1 78.2 25 0.7±0.1 143.7(56.4- 65.3 9328(1756- 144. 10.8(10 Organic SB 6 465) 854447) 2 ) Elkhorn 2 75.1 31 1.1±0.2 204.8(119- 93.1090 3531(1439- 54.6 5.7(10) Conv SB 4 343) 9 25271) a:% Mortality stands for the % mortality of eggs at the maximum labelled rate of hexythiozoxon Conv= Conventional field; SB = strawberry; RB = raspberry; BB = blackberry
Our results with abamectin are confusing The greatest RR we have calculated in Washington was 107.64 and this was from a hopyard in Mabton, WA. Our results from California (Table 3) are showing that most of the populations were susceptible or moderately resistant to abamectin. It is our intention to try to test some additional mite populations collected from Watsonville and Salinas in late summer 2018. We believe that we may have held these mites in colony for too long. However, in previous studies we have observed that resistance to abamectin stays fairly heritable in populations for multiple generations when the population is held in colony and is not exposed to any toxins including abamectin. Table 3. Toxicity of abamectin to T. urticae populations collected from Strawberry plots in California Population % N Slope±S LC50(95 RR5 LC90(95 RR9 χ² (df) Mortality E % CI) 0 % CI) 0 a Susceptible, 100 24 1.4±0.2 0.8(0.5- 1 6.7(4.2- 1 6.2(16) WA 1 1.3) 13.4)
40
Oxnard 1 60 27 1.65±0.3 7.8(5.8- 9.8 46.2(27.5- 6.9 3.8(13) Conv SB 0 10.4) 127.4) Oxnard 2 72 23 1.1±0.2 2.2(1.2- 2.8 31.9(15.4- 4.8 18.6(13 Organic SB 5 3.8) 124.8) ) Oxnard 3 Organic SB Oxnard 4 61.4 28 1.3±0.2 7.7(4.5- 9.6 72.3(29.8- 10.8 26.2(13 Conv RB 0 14.6) 361.2) ) Salinas 1 60.8 25 1.9±0.6 8.5(6.3- 10.6 39.7(19.1- 5.9 1.7(10) Conv SB 9 16.1) 219.7) Wat 1 89 35 0.78±0.1 1.0(0.25- 1.3 44.2(14.4- 6.6 21.5(10 Organic SB 1 2 2.1) 364.6) ) Wat 2 83.7 23 0.98±0.1 1.6(0.89- 2 40.5(20.6- 6.0 5.7(10) Organic BB 9 2 2.5) 115.7) Elkhorn 1 85.5 27 3.4±0.4 4.9(4.0- 6.1 11.7(9.4- 1.8 6.9(13) Organic SB 4 5.9) 16.3) Elkhorn 2 44.5 25 1.5±0.5 14.1(9.5- 17.6 98.4(31.8- 14.7 8.7(10) Conv SB 3 41.8) 272.6) a:% Mortality stands for the % mortality of mites at the maximum labelled rate of Abamectin on strawberry Conv= Conventional field; SB = strawberry; RB = raspberry; BB = blackberry
Bioassay experiments on spirodiclofen and acequinocyl have also been completed. The data is yet to be compiled. At present we have defined molecular markers from mite populations in Washington State that are associated with acaricide resistance to bifenthrin, bifenaztae, spiromesifen, fenpyroximate, hexythiozox, etoxazole, clofentazineand cyflumetofen. We are presently working on acequinicyl. Markers for abamectin resistance have been identified in Europe, South Korea, and Israel. Our populations in Washington State have not tested positive for any of these point mutations. Several of the California mite populations we sampled have tested positive for these point mutations associated with abamectin resistance. We have submitted a research proposal to the California Strawberry Commission and will complete further studies if the proposal is positively received.
41
LYGUS EFFICACY TRIALS IN ALFALFA PRODUCED FOR SEED 2018. D. Walsh & D. Groenendale Environmental and Agricultural Entomology Laboratory WSU IAREC 245106 N. Bunn Rd. Prosser, WA 99350 [email protected] Insecticides were screened for their ability to control Lygus bugs and alfalfa weevil on alfalfa produced for seed and for their potential negative impact on beneficial arthropods in mid summer 2018. Field plots were established at the irrigated Agriculture Research and Extension Center near Prosser, WA. Established plots were 360 ft2 (18 ft. wide and 20 ft. long) and all treatments were replicated 4 times in a randomized complete block design. Insecticides were applied to mimic grower timing at the post-bloom period of production.
Treatments were applied on August 9, 2018 using a CO2-powered backpack sprayer equipped with a four-nozzle boom using 19.8 gallons of water per acre as a carrier. Five 180° sweeps per plot were used post- application on August 10, 14, and 24 as a means to sample Lygus and other arthropod abundance including aphids, spiders, big-eyed bugs, minute pirate bugs, assassin bugs, lace wings, lady bird beetles and weevils. Abundance counts for Lygus, spiders, damsel bugs, and alfalfa weevils are detailed in this report. The abundance of other arthropods was inconsequential. Analysis of variance (ANOVA) was conducted on insect abundance counts for each pest on each respective sample date. The insect abundance counts for each pest by insect treatment was then compared to the untreated control population means in pair wise t-tests. Transform was a superior insecticideand provided control of Lygus that was consistently equal to or superior to the pyrethroids including Mustang Maxx and Warrior II. All treatment effects were done by 21 days after treatment. It should be noted that these plots were established on a 1acre block of poorly managed alfalfa hay on the WSU IAREC Roza unit. Section 18 Emergency Exemptions were issued for Transform (sulfoxaflor) in 2018 in Washington State and Idaho. A Crisis Section 18 was issued in Oregon. We anticipate that these 3 states will continue to submit Section 18 requests for Transform until Corteva receives registration of Transform on their Tier 2 crops. Alfalfa is among the crops on Corteva’s Tier 2 list. Growers of alfalfa seed should soon have this 2nd “safer” insecticide for use on blooming alfalfa once Transform is registered. We have determined that if growers of alfalfa produced for seed follow simple recommendations like limiting insecticide sprays to evening hours with products like Beleaf and Transform that Lygus bugs can be controlled with relative safety and minimal harm to pollinating bees. My present recommendations for Lygus control on alfalfa include a pre-bloom “cleanup spray. There are several effective pyrethroids and organophosphate products registered as well as some effective premix products that contain OPs and pyrethroids. During early bloom the insecticide of choice is Beleaf and later in bloom as the plants desiccate Transform is the insecticide of choice. Growers are limited to 2 applications of Beleaf and Transform. Some growers are seriously considering using Transform as their pre-bloom cleanup spray given Transform’s efficacy and its softer footprint on beneficial arthropods. Other factors include the fact that Transform does not appear to flare mite outbreaks compared to the pyrethroids registered for use on alfalfa grown for seed. Most alfalfa seed fields require mid-summer
42
acaricide sprays after pyrethroids have been used in late spring. Days after Lygus Lygus Lygus Damsel Alfalfa Date treatment Treatment Adult large nymph small nymph Spider bugs weevil 8/10/2018 1 Control 19 11.5 18.25 2 1 1.25 8/10/2018 1 Beleaf 50 SG 9.5 8.25 6.25* 5 2.25 1.75 8/10/2018 1 Biological Soil & foliar 19.75 11.5 15.25 3.5 1.75 0.5 8/10/2018 1 Cobalt Advanced 5.5* 4.75* 0.75* 3.25 0 1.25 8/10/2018 1 Mustang Maxx 4.25* 5.5 9.75 1 0 2.75 8/10/2018 1 Naled 19.5 9.25 7 3.5 0 0 8/10/2018 1 Sivanto 29.25 8 18.75 3.25 3 0.5 8/10/2018 1 Stallion 3* 1.75* 3.25* 2 0.25 0.25 8/10/2018 1 Transform1.5 8.25* 4* 5.25* 5.75 3.25 0.5 8/10/2018 1 Transform2.25 6.25* 2.25* 4.25* 6.5 1.75 0.25 8/10/2018 1 Warrior II 4.75* 6.5 10.5 1.75 0 2
8/14/2018 5 Control 12.25 8.5 8.25 3.5 0.75 1.25 8/14/2018 5 Beleaf 50 SG 14.5 5 6.25 6.5 1 1.75 8/14/2018 5 Biological Soil & foliar 12 5.25 3.75 6.75 3.75 0.75 8/14/2018 5 Cobalt Advanced 6.75* 2* 1* 0.25 0.25 0 8/14/2018 5 Mustang Maxx 4.75* 7.5 7 1.25 0.5 6.5 8/14/2018 5 Naled 21.25 7.75 5.5 7.25 2.5 0.5 8/14/2018 5 Sivanto* 15.75 6.5 7.5 4.5 1.25 1.75 8/14/2018 5 Stallion 7.75 2.25 1.5* 5.25 0 4 8/14/2018 5 Transform1.5 12.75 0.5* 0.5* 7 0.25 1 8/14/2018 5 Transform2.25 8 2.5* 2.25* 5 1 1.5 8/14/2018 5 Warrior II 8.25 8.5 3.5 3.75 1 9
8/24/2018 15 Control 17.75 12.5 10 3.25 1.25 2 8/24/2018 15 Beleaf 50 SG 10.75 5.25 15 4.75 0.75 1.25 8/24/2018 15 Biological Soil & foliar 13.5 6.5 14.5 4.5 1.75 0.5 8/24/2018 15 Cobalt Advanced 11.25 1.75* 11 2 0.25 1 8/24/2018 15 Mustang Maxx 11.25 8.25 23.75 2 0 3 8/24/2018 15 Naled 12.5 3.75 16 4.75 1.75 0.75 8/24/2018 15 Sivanto* 13.25 10.25 19.75 2.5 0 0.75 8/24/2018 15 Stallion 13.5 0.75* 24 2.25 0.5 3.25 8/24/2018 15 Transform1.5 21 1.25* 21.25 3.75 1 1 8/24/2018 15 Transform2.25 16.25 4.5 14.75 4.75 0.25 1.25 8/24/2018 15 Warrior II 15.5 4.75 10.25 1.25 0.75 4 */ treatment means are significantly lower than in the untreated Control plots
43
2018 ACARICIDE EFFICACY TRIALS IN WASHINGTON STATE HOPYARDS D.B. Walsh Washington State University Irrigated Agriculture Research and Extension Center 24106 N. Bunn Road, Prosser, WA 99350 [email protected] 2018 Acaricide Efficacy Field Trials Eighteen acaricide treatments were applied to hops cv. ‘Tomahawk’ on the Roza Unit at WSU Prosser on July 27, 2018 by airblast sprayer in 200 gallons of water per acre to 4 replicates of seven hills with 2 strings per hill in 14-ft rows with plants spaced every 3.5 feet in row (Table 1).
Table 1. Acaricides applied
Tractor /Pak blast Product Active Ingredient Rate/Acre 1 Control (Untreated) None none none 2 GWN-1518 ? 24 fl oz/acre 3 GWN10666 ? 24 fl oz/acre 4 Magister SC Fenazaquin 36 fl oz/acre 5 GWN10666 ? 24 fl oz/acre +Magister SC Fenazaquin 10 fl oz/acre 6 GWN10666 ? 24 fl oz/acre +Magister AC Fenazaquin 32 fl oz/acre 7 Nexter Pyridaben 17 fl oz/acre 8 GWN10666 ? 24 fl oz/acre + Nexter SC Pyridaben 17 fl oz/acre 9 Envidor Spirodiclofen 24.7 fl oz/acre + Nexter SC Pyridaben 17 fl oz/acre 10 Viglilant 4SC ** Bifenazate 24 fl oz/acre 11 Zeal SC Etoxazole 6 fl oz/acre 12 V-10470 ? 34.5 fl oz/acre 13 V-10471 ? 38.5 fl oz/acre 14 V-10470*** ? 34.5 fl oz/acre 15 TetraCURB Concentrate Rosemary Oil 128 fl oz/acre 16 NOF02 Rosemary Oil 128 fl oz/acre 17 TetraCURB Concentrate Rosemary Oil 64 fl oz/acre 18 NOF02 Rosemary Oil 64 fl oz/acre * add 1% v/v oil +water conditioner label rate oz/acre ** Plus buffer at 5.5-6.5 and Crop oil at 1% v/v *** NIS 0.25%v/v or 0.125%v/v depending on protocol
44
Plots and rows were offset with 7 untreated hills at either end and to each side of the treated plot. A pretreatment sample was collected and analyzed from each plot from the hopyard on July 20, 2018. Acaricide efficacy was evaluated 3, 7, and 13, days following the applications (on July 30, August 3, August 9, and August 16) (Table 2). Mite abundance was calculated using a mite-brushing technique. On each sample date 10 leaves per replicate plot were collected and labeled and placed in an ice chest. When all sample leaves were collected they were transported to the Environmental and Agricultural Entomology Laboratory located at WSU Prosser. The 10 leaves from each replicate plot were then mite brushed onto a glass plate. Subsequently the number of spider mites, spider mite eggs, predatory mites, and other beneficial arthropods present were qualified and quantified. Calculations were made to quantify the estimated abundance of mites and other arthropods per leaf. All other arthropods counted including predatory mites were inconsequential and there were no differences among treatments in the abundance of predatory arthropods. Spider mite abundance was moderate this year peaking at around 55 mites per leaf in the untreated control plots on August 9, thirteen days after treatment.
Table 2. Results of 2018 acaricide efficacy trial. Data is detailed by the mean number of mites or mite eggs per leaf ± the standard deviation of the mean
7/20/2018 7/30/2018 8/3/2018 8/9/2018 Treatment mite/leaf mite/leaf mite/leaf mite/leaf control 1.45 0.97 10.40 9.87 15.70 8.28 55.47 49.82 Gowen-1518 / TriTek 1% 2.30 3.13 5.30 5.27 40.80 37.58 16.93 10.78 Gowen-10666 / TriTek 1% 1.25 2.05 5.90 3.41 30.60 9.03 36.93 6.87 Magister 2nd Control No chemical left 0.25 0.43 3.85 2.97 14.30 5.70 13.20 5.49 Gowen-10666+ MagisterSC / TriTek 1% 0.35 0.50 1.30 1.14 10.30 3.86 12.00 2.59 Gowen-10666+ MagisterSC / TriTek 1% 1.05 1.23 4.70 1.28 18.70 10.46 22.67 16.73 Nexter / TriTek 1% 1.00 0.93 2.35 2.25 19.00 17.54 30.00 11.92 Gowen-1066+Nexter SC / TriTek 1% 2.45 2.80 3.40 4.20 13.20 7.56 24.67 14.87 Envidor+NexterSC /TriTek 1% 1.40 0.97 4.10 3.31 18.10 5.44 18.80 16.12 Vigilant 4SC** 0.30 0.33 6.90 5.82 12.20 3.23 16.80 8.98 Zeal SC 0.45 0.78 2.65 2.33 10.00 5.37 25.07 11.69 V10470 2.05 3.44 4.45 2.46 9.20 3.78 17.60 12.17 V10471 0.85 0.54 6.00 3.64 26.80 25.27 18.93 8.15 V10470*** 1.55 0.96 5.50 5.20 18.00 8.08 29.20 23.76 TetraCURB Concentrate 0.70 0.88 5.20 6.93 38.60 36.90 19.20 7.53 NOF02 1.05 0.77 3.35 2.70 29.90 14.94 12.00 1.42 TetraCURB Concentrate 0.80 0.55 5.30 4.21 15.20 6.69 11.87 3.71 NOF02 1.45 2.17 13.50 14.88 45.30 30.40 17.60 9.60
eggs/leaf eggs/leaf eggs/leaf eggs/leaf control 0.55 0.61 20.90 19.06 31.10 4.07 129.33 50.33 Gowen-1518 / TriTek 1% 0.90 1.06 11.90 9.55 94.10 81.20 118.00 41.48 Gowen-10666 / TriTek 1% 0.10 0.10 12.55 7.22 70.80 20.93 109.33 26.65 Magister 2nd Control No chemical left 0.00 0.00 14.05 13.62 48.50 21.76 115.07 34.03 Gowen-10666+ MagisterSC / TriTek 1% 0.45 0.30 1.45 0.91 31.00 11.32 132.93 46.64 Gowen-10666+ MagisterSC / TriTek 1% 1.15 1.20 6.20 3.38 47.80 8.84 99.07 27.91 Nexter / TriTek 1% 0.15 0.26 5.95 4.67 21.30 13.07 262.53 45.27 Gowen-1066+Nexter SC / TriTek 1% 1.05 0.89 4.45 5.80 64.60 32.78 93.87 47.54 Envidor+NexterSC /TriTek 1% 0.65 0.65 6.90 4.15 55.40 31.76 90.93 61.57 Vigilant 4SC** 1.10 1.18 10.45 8.25 27.00 11.19 116.13 31.68 Zeal SC 0.55 0.84 3.55 2.40 44.80 27.62 216.00 106.79 V10470 0.30 0.52 6.25 1.51 24.30 6.99 140.27 59.38 V10471 0.95 0.95 8.75 5.71 106.80 125.26 125.73 25.81 V10470*** 0.35 0.22 14.40 8.03 51.50 30.75 127.33 85.89 TetraCURB Concentrate 0.25 0.43 7.15 7.91 127.00 169.45 162.27 135.20 NOF02 0.40 0.49 10.50 6.97 82.30 41.99 109.20 29.81 TetraCURB Concentrate 0.35 0.41 10.40 1.32 25.50 8.91 91.07 50.39 NOF02 0.35 0.38 29.00 24.54 349.60 383.35 115.40 47.80
45
LANDSCAPE EFFECT ON LYGUS MOVEMENT AND CROP SELECTION
G. Shrestha, J. Antwi, and S.I. Rondon Oregon State University, Hermiston Agricultural Research and Extension Center 2121 South First Street, Hermiston, OR 97838 [email protected], [email protected]
In the Pacific Northwest, Lygus bugs complex is perceived as a major threat to potato production systems. This insect inflicts direct damage to potatoes through both feeding and oviposition; it is also suspected that Lygus bugs may carry pathogens. Despite our efforts, it remains unknown, if Lygus feeding damage affects potato tuber yield and quality. There is already a management program in place, which includes pesticide control; control is effective but is limited because of the high movement capability of Lygus adults and immatures. Thus, the overall study aims to determine the effect of landscape on Lygus movement and crop selection preference. Our preliminary data indicates that Lygus prefer some potato varieties such as Alturas compared to Burbank, Umatilla or Rangers. Our hypothesis is in tune to the vertical and spatial distribution of Lygus at the plant level or at the landscape level. Understanding insect pest movement behavior is crucial for managing generalist insects that feed on multiple host plant species.
46
EVALUATING INSECTICIDE RESISTANCE IN ONION THRIPS
Tim Waters1, Adekunle Adesanya2 and Doug Walsh2 Washington State University Extension1 Washington State University Department of Entomology2 [email protected] Onion thrips, Thrips tabaci, are the key insect pest of onions. Thrips feeding results in economic loss by reducing onion quality and size. Onion thrips also vector a tospovirus (IYSV) that is the causal agent of Iris Yellow Spot disease. The pest management strategy for most commercial onion farms focusses on the application of different chemistries of insecticides to reduce the infestation of onion thrips. Previous study by the Walsh lab at IAREC Prosser, documented the universal incidence resistance to pyrethroids among onion thrips populations in Washington State. The source of resistance is through mutations in the voltage-gated sodium channel; the target site of pyrethroids such as lambda-cyhalothrin. Another class of insecticide commonly used for thrips control in onion field is the carbamates oxamyl (Vydate ®) and methomyl (Lannate® LV). The goal of this study is to characterize the resistance status of onion thrips populations in Washington onion fields to carbamates, specifically methomyl and oxamyl. Detailed herein are our results for methomyl and oxamyl resistance status. Methomyl and oxamyl are often applied multiple times to individual onion fields over the course of the growing season and both methomyl and oxamyl have been in use on onions for over 25 years. Due to regulatory and environmental issues, the rate of development of insecticide resistance typically far outpaces the discovery and registration of new chemistries/products. Hence, following insecticide resistance management practices are essential to preserve the efficacy of the currently available insecticides.
Full dose response bioassays were performed on onion thrips larvae from five commercial onion fields (one organic and four conventional) in central Washington in 2018. The bioassays were performed in situ in the fields for a more precise resistance/susceptibility quantification using a protocol adapted from a previous study.
The thrips population from the organic onion farm was the most susceptible to oxamyl and methomyl with 100% mortality at the labeled rate of both insecticides. We observed significantly reduced efficacy of oxamyl and methomyl in thrips populations from conventional onion farms. These results clearly demonstrated that methomyl has been overused in conventional onion fields and that new strategies need to be developed to achieve thrips control without development of further resistance.
Funding for this project was provided by: the Washington State Commission on Pesticide Registration and the Columbia Basin Onion Research Committee.
Thanks to Hartley Farms, CSS Farms, and Lenwood Farms for allowing thrips from their onion fields to be assayed.
47
SECTION V Potato Pests
48
CAN THE PNW REESTABLISH POTATO IPM PROGRAMS
Alan Schreiber, Tim Waters (Washington State University) Agriculture Development Group, Inc. 2621 Ringold Road Eltopia, WA 99330 (509) 266 4348 [email protected]
Twenty years ago, Pacific Northwest potato growers were largely concerned about Colorado potato beetle, green peach aphid, wireworm and occasionally two-spotted spider mites. In 2018, a PNW grower may face these four insect pests but also, western Lygus bug, western flower thrips, potato tuberworm, beet leafhopper, three species of lepidopterous pests and potato psyllids. Especially impactful to potato insect pest management programs has been the recent arrival of potato psyllid and the sometimes accompanying bacterial disease that causes zebra chip. Grower efforts to eliminate the possibility of zebra chip in commercial potatoes has essentially wiped out potato insect pest management programs.
Currently growers apply insecticides on a calendar schedule and commonly apply ten or more insecticides in a season. Applications of these insecticides are known to foment aphid and mite outbreaks. Research by Schreiber in 2017 established for the first time that applications of insecticides targeting potato psyllids can cause outbreaks of western flower thrips. This finding is similar to WSU’s Tim Waters results showing that pyrethroid applications in onions can cause onion thrips outbreaks.
An effort lead by the Northwest Potato Research Consortium’s Andy Jensen and OSU’s Paul Jepsen have initiated an effort to try and reestablish potato IPM programs in the Pacific Northwest. The vehicle for this effort is the Potato IPM Workgroup (a.k.a. Resilient Potato Production Initiative Group.
Research by Schreiber in 2018, found that intensive sampling and use of higher action thresholds resulted in a substantial reduction in insecticide applications as compared to a more standard high input, risk averse potato pest management approach.
Plans are being made to expand this effort in 2019 to commercial fields that will be intensively sampled with presubscribed action thresholds and use of selective insecticides. These fields will be compared to fields that are managed in a more conventional manner.
49
TIMING APPLICATIONS FOR CONTROL OF LYGUS SPP. IN POTATOES D. I. Thompson, and S. I. Rondon Oregon State University, Hermiston Agricultural Research and Extension Center 2121 South 1st Street Hermiston, OR 97838 [email protected], [email protected]
Lygus spp. are an emerging concern in the Columbia basin as they affect many crops including potatoes. As chemical applications are underway in potato fields to control Lygus bugs, growers and field men do not have much information on the real effect Lygus may have on yield and best chemistry and appropriate timing of application(s). In 2018, the OSU Irrigated Agricultural Entomology Program conducted a field trial to determine pesticide efficacy and timing of application to control Lygus nymphs and adults. Plots were 7.6 m long and 8 rows wide with a .86 m row spacing. Applications were made with a Tractor mounted CO2 sprayer at 30 psi pressure, with Tee Jet A11002VS nozzles spaced 20 inches on a 12 ft boom, with an application rate of 30 gallons per acre. Each of the 14 treatments was replicated 4 times for a total of 56 plots. Standard agronomic practices were followed for the duration of the trial e.g. Applications were made on a weekly basis starting at the first Lygus detection. Each week, there were 14 treatments, including the control, that were based on gradually eliminating insecticide applications weekly. Treatments were applied starting the third week of May. Insecticides were applied as followed: (1) oxamyl (Group 1A), (2) permethrin (Group 3), (3) flocnicamid (Group 29), and (4) sulfoxaflor (Group 4C) followed by 1, 2, 3, 4, 1, etc. Each treatment was then excluded from the treatment rotation on a weekly basis until the last treatment was made at 13 weeks. Insect sampling was conducted weekly from the time of emergence until vines were killed and mowed for harvest. Our data suggest that nymphs are easier to control compared to adults. None of the pesticides, when analyzed individually, controlled Lygus adults season long; this may be due to adults highly mobility. Although there were not statistically differences in yield, some trends were observed.
50
THE POTATO PSYLLID IN THE COLUMBIA BASIN: PEST MANAGEMENT STRATEGY Maria Montes de Oca and S.I. Rondon Oregon State University Hermiston Agricultural Research and Extension Center 2121 S First Street, Hermiston OR 97838 [email protected], [email protected]
Since 2011, there are continuous efforts in combating zebra chip disease in the Columbia Basin. Zebra chip caused by the pathogen known as Candidatus Liberibacter solanacearum, is a destructive disease affecting potatoes, and has the potential to cause significant economic losses. Zebra chip is transmitted by the potato psyllid Bactericera cockerelli Šulc. The potato psyllid is a phloem- feeding insect that has a limited host range across including a couple of plant families including Solanaceous crops and weeds. When an infected psyllid (‘hot’) feeds on a healthy plant, the bacterium travels through the phloem of the plant down to the tubers causing higher than normal sugar concentration. That concentration turns the flesh of the potato dark, which is evident while frying. Though the defect is harmless to consumers, the flavor of the product is altered, making infected tubers unmarketable. To date, most strategies to avoid ZC infection in potato fields have been vector control through the regular use of pesticides. Currently, our group is investigating alternative means of control. In 2016 and 2017, the OSU Irrigated Agricultural Entomology program located in Hermiston OR, conducted some greenhouse trials to determine the benefits of using different applications and concentrations of Calcium. Going back to our biology days, we know that Calcium is a key component of cell walls, because it helps build a strong structure and ensures cell stability. Thus, our hypothesis is that Calcium enriched cell walls will be more resistant to bacterial attack. Plants require calcium as it plays an important role in their growth and development. The health of cell membranes is necessary for the overall survival of the plant cell, and that can only be done with sufficient calcium around the membranes. In our experiment, four calcium concentrations plus a control (water) were applied to four potato plants per treatment. A week later, “hot” psyllids were released into clip cages. After a week, clip cages were removed and plants were observed daily. Same procedure was followed with clean psyllids. Plants were taken to yield and number of tubers per plant per treatment were counted. Our data revealed some interesting trends and differences.
51
EFFECT OF SELECTED INSECTICIDES AGAINST COLORADO POTATO BEETLES AND ITS NATURAL ENEMIES IN THE COLUMBIA BASIN
P. Yang1, M.S. Crossley2, and S.I. Rondon1 1Oregon State University, Hermiston Agricultural Research and Extension Center, 2121 S 1st Hermiston, OR 97838; 2University of Wisconsin-Madison, 1630 Linden Dr. #637 Madison, WI 53706 [email protected]; [email protected]; [email protected]
Over the last century, the U.S. potato (Solanum tuberosum L.) industry has suffered from one of the most important insect defoliators, the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae). This insect has a history of repeated adaptation to different insecticides modes of action, while exhibiting a geographic pattern of decreasing insecticide resistance from east to west. There are multiple reports of insecticide resistance for eastern L. decemlineata populations; however, to our knowledge, there are no reports for western populations. Our program is interested in developing baseline information to support the knowledge related to L. decemlinata resistance situation in the western U.S. In the Columbia Basin of southeastern Washington and northeastern Oregon, potato is a dominant cash crop. More than 35,000 acres of potatoes are planted annually in Oregon alone, yielding about 550 hundred weight per acre. Leptinotarsa decemlineata, a pest native to Central Mexico, has a close-fitting evolutionary relationship with plants in the family Solanaceae, thus potentially capable of causing significant losses. The heavy reliance of pesticides for the control of this insect, has led to a potential problem that must be understood while searching for alternative means of control. In this study, several insecticides (imidacloprid, spinosad, chlorantraniliprole, and abamectin), widely used in western states were measured against larval and adult L. decemlineata. Three locations in the Columbia Basin were selected including one location from the Midwest. Larval and adult insecticide LD50’s and mean percent mortality were generated. For this experiment, larvae were reared from eggs collected from commercial fields in the region; adults were also collected to augment the population of L. decemlineata in our colonies. Topical bioassays were performed with various doses (10, 100 or 1000 ppm) plus a control. Mortality was recorded 2 days after treatment, and the LD50 was determined using a logit regression. Larvae were considered dead if the tissue was necrotic; adults were considered dead if they did not show any type of movement. Additionally, in a field study, pesticides used at planting (imidacloprid, thiamethoxam) were tested to determine their effectiveness controlling L. decemlineata, and an important parasitoid of L. decemlineata, Myiopharus doryphorae (Diptera: Tachinidae). Results in both studies vary depending on location and insecticide a.i. Our data will serve as baseline for future resistance studies.
52
SECTION VI Pests of Wine Grapes & Small Fruits
53
CONTROLLING SPOTTED WING DROSOPHILA IN ORGANIC BERRIES
Alan Schreiber and Steve Song Agriculture Development Group, Inc. 2621 Ringold Road Eltopia, WA 99330 (509) 266 4348 [email protected]
Eleven years ago, there was an estimated 600 acres of organic blueberries in the United States. By the end of 2018, Washington will be approaching 4,000 acres of organic blueberries and has already established itself as the leading producer of this crop in the world. When this area and the additional areas of blueberries are transitioning to organic status are fully bearing and fully transitioned, Washington will probably have between 80 and 100 million pounds of organic blueberries. Acreage of this crop is expanding due to the favorable prices received and the relative lack of insect and disease pressure the industry has enjoyed. More than 90% of organic blueberries are located in eastern Washington. Prior to 2012, virtually no insecticides or fungicides had been applied to blueberries grown in eastern Washington, while blueberries produced in western Washington have significant disease and insect pressure. Spotted wing drosophila (SWD) was detected in eastern Washington in 2010 but was not sufficiently widespread, and presented in sufficient numbers or was not noticed prior to 2012. The year 2012 was a turning point for blueberry production. Several growers deployed significant SWD programs, other growers who were less aware of the pest or less sophisticated in the SWD control programs suffered significant losses. For fresh blueberries, detection of a single larvae per pallet results in rejection of the whole pallet. Processed blueberries have lower standards, but production of blueberries for the processed markets require a competent SWD control program. Several shipments of blueberries from eastern and western Washington have been rejected due to the presence of SWD. The Washington Blueberry Commission is under significant pressure to respond to this situation. For conventional growers, there are a number of insecticidal options available. Unfortunately, only one organic insecticide (Entrust, spinosad, Dow AgroSciences) has been demonstrated to have sufficient efficacy against SWD, prior to the beginning of this research program. Organic blueberry growers rely heavily on Entrust, and the Washington (and California and Oregon) organic blueberry industry is very dependent on this product. One of the challenges growers have is that there is a limit on the amount of this product that can be applied during the course of the season, resulting in usage of lower rates in order to extend coverage throughout the season. The registrant of Entrust, Dow AgroSciences, now requires use of an alternative, effective insecticides after every two applications. Growers currently question whether there is anything effective enough to rotate with Entrust. SWD has been documented as having developed resistance to Entrust in blueberries in the Watsonville area of California. While strong scientific data may be lacking to support resistance in SWD to Entrust, two things are known: 1) Entrust is not working as well as it once did against SWD in the areas where it has been used the longest time , and 2) such heavy reliance on a single mode of action, year after year in a pest with a propensity to develop resistance is a risky situation. The
54
Washington blueberry industry is desperate to develop new organic products for SWD control. In a late season SWD blackberry trial, Schreiber’s group has developed successful data for three organic products demonstrating that 1) he can complete a SWD trial, 2) addition of sugar improves efficacy of products not previously known to control SWD and 3) there are other products potentially available. The data collected in 2017 has developed a single program that appears to be comparable or better than an Entrust only program. Materials and Methods During the summer of 2018, the staff of the Agriculture Development Group, Inc. started a research trial investigating the efficacy of different organic insecticides and their combination/rotation for the control of spotted wing drosophila (SWD) in blackberry, compared to conventional insecticides. The experimental design for this trial was a RCB with 4 replications and plot sizes of 10ft x 25ft. Applications for this trial were made with an over the row sprayer calibrated to apply treatment sprays at 30 gallons per acre (Photo 1). Applications were initiated at first appearance of SWD on July-19. Treatments of this trial had different combinations of products and application timings. Applications A, B, C, D, E, F were made on July 19 and 26, August 2, 9, 16, and 23, respectively. 20 berries per plot were collected before each application, in additional of August 30 (7 days after application F=7 DAF) then soaked in salt water for 30 minutes before the amount of SWD larvae was counted (Photo 2). The sum of SWD collected at all dates for each treatments was calculated to represent the study total #.
Results and Discussion No phytotoxicity was observed for all treatments at all application timings. During this study, significant lower than untreated check results was only observed at 7 days after application B (DAB) and study total SWD, with numerically differentiations in other rating dates. Both rates of IKI3106+acetamiprid (treatments 1 and 2) maintained less than untreated control SWD larvae population consistently through 7 days after application B (DAB) to 7 days after application F (DAF) with up to 70% control at 7 DAB (Table 1 column 3; Figure 1). IKI3106+acetamiprid had no obvious dosage effect (higher rate had same SWD control as low rate) with a 35% control of study total SWD (Table 1 column 8; Figure 2). It is important to mention that the control effect weakened after 7 DAB when the SWD population increased dramatically and no significant control can be observed in the total SWD data. Similar trend was observed for most treatments during the study. Combination of Grandevo and sugar (treatment 6) also had 59% control by 7 DAB and the control efficacy increased to 83% when pre-treatment of Jet Ag was applied (treatment 8) (Table 1 column 3; Figure 1). Similarly, the pre-treatments of Jet Ag improved the control efficacy of Venerate from 43% to 52% (treatment 7 VS. treatment 9). Apparently, the addition of pre-treatment of Jet Ag generally improve the control efficacy of both Grandevo and Venerate throughout the whole study with slightly reduced study total SWD from Jet Ag added treatments which reduced total SWD from 252 to 242 by treatment 8 and 260 to 222 by treatment 9 (Table 1 column 8; Figure 2). The highest rate of V-10433 at 22 fl oz/a and Veratran D (15 lb/a) had significantly less SWD larva than untreated at 7 DAB with 88% and 64% relative control (Table 1 column 3; Figure 1). Meantime, V-10433 at lower rates (8 and 11 fl oz/a in treatments 11 and 12) only had numerically 55
less SWD than untreated, but the rotation of v-10433 at 6 fl oz/a with Entrust consistently exhibited enhanced SWD control than Entrust alone with 81% control at 7 DAB and 37% total SWD control while Entrust alone had 73% and 31% (Table 1 columns 3 and 8). Delegate at low or high rate had statistically the same level of SWD infestation with 65 and 86% control by 7 DAB, while the effect weakened in later rating dates with only numerically less study total than untreated. However, the higher rate (6 oz/a) Delegate had the second lowest total SWD (following Warrior II) with 39% overall control, indicating a positive dosage control effect especially in the later rating dates with higher SWD pressure (Table 1 column 8; Figure 2). In contrast, conventional insecticides like Exirel and Warrior II showed only 56% control by 7 DAB. However, Warrior II was the only treatment showed significantly less study total SWD than untreated check with a 41% overall control (Table 1 column 8; Figure 2). In summary, IKI3106+acetamiprid at either 52 (treatment 1) or 78 (treatment 2) g a.i./ha, rotation of Entrust and V-10433 (treatment 16) or Entrust alone (treatment 17), Delegate at 6 oz/a (treatment 20), and Warrior II (treatment 22) performed the best with statistically the same total SWD control between 31% to 41%. Delegate at lower rate 4.5 oz/a and Veratran D at 15lbs/a also had good performance with a 25 % total SWD control. Other treatments, especially Jet Ag pretreatment followed by Grandevo or Venerate (treatment 8 and 9) showed some potential yet the control efficacy was very inconsistent fluctuation at different rating date, which also resulted in a <13% or even negative total control (higher # than untreated). Considering the very high SWD pressure, the best performed organic treatments showed very promising (equal or better than Entrust and Warrior) SWD control efficacy, suggesting great potential of rotation for reduced resistance risks.
56
Table 1. ANOVA mean separation table for all treatments at different dates.
Pest Name SWD SWD SWD SWD SWD SWD SWD SWD Crop Name Blackberry Blackberry Blackberry Blackberry Blackberry Blackberry Blackberry Blackberry Rating Date 19-Jul 26-Jul 2-Aug 9-Aug 16-Aug 23-Aug 30-Aug Rating Type count count count count count count count Study total Rating Unit # # # # # # # # Days After First/Last Applic. 0 0 7 7 14 7 21 7 28 7 35 7 42 7 Trt Treatment Rate Appl No. Name Rate Unit Code 1* 2* 3* 4* 5* 6* 7* 8* 1 IKI-3106+Acetamiprid 52 g ai/ha ABCDE 0 a 2 a 8.5 def 12 a 23 f 45 a 83 a 174 def 2 IKI-3106+Acetamiprid 78 g ai/ha ABCDE 0 a 0 a 10.5 c-f 15 a 29 ef 56 a 65 a 174 def 3 IKI3106 100SL 60 g ai/ha ABCDE 0 a 0.5 a 12.3 c-f 37 a 70 b-f 41 a 72 a 233 b-f 4 Voliam Flexi 168 g ai/ha ABCDE 0 a 0.5 a 9 def 54 a 47 def 76 a 51 a 236 b-f 5 Minecto Pro 143 g ai/ha ABCDE 0 a 0.8 a 8.8 def 51 a 39 def 44 a 118 a 261 b-f 6 Grandevo 3 lb/a ABCDEF 0 a 0.8 a 11.5 c-f 26 a 51 def 71 a 98 a 258 b-f NuFilm P 1 pt/a ABCDEF suger 5 % v/v ABCDEF 7 Venerate 3 qt/a ABCDEF 0 a 0.3 a 16 b-e 15 a 86 bcd 79 a 64 a 260 b-f NuFilm P 1 pt/a ABCDEF suger 5 % v/v ABCDEF 8 Jet Ag 1.2 % v/v ABCDEF 0 a 0 a 4.8 f 24 a 56 def 79 a 78 a 242 b-f Grandevo 3 lb/a ABCDEF NuFilm P 1 pt/a ABCDEF suger 5 % v/v ABCDEF 9 Jet Ag 1.2 % v/v ABCDEF 0 a 1 a 13.5 c-f 48 a 32 ef 53 a 75 a 222 b-f Venerate 3 qt/a ABCDEF NuFilm P 1 pt/a ABCDEF suger 5 % v/v ABCDEF 10 V-10433 4 fl oz/a ABCDEF 0 a 0 a 28.8 a 28 a 141 a 94 a 118 a 410 a 11 V-10433 8 fl oz/a ABCDEF 0 a 1.8 a 27.8 a 19 a 141 a 117 a 101 a 407 a 12 V-10433 11 fl oz/a ABCDEF 0 a 0.3 a 17.8 a-d 29 a 121 ab 65 a 57 a 290 bc 13 V-10433 22 fl oz/a ABCDEF 0.3 a 0.8 a 3.5 f 17 a 109 abc 87 a 97 a 315 ab 14 AZERA 2.5 pt/a ABCDEF 0 a 3.5 a 21 abc 22 a 69 b-f 54 a 96 a 265 b-f 15 VERATRAN D 15 lb/a ABCDEF 0 a 0 a 10.3 c-f 19 a 54 def 54 a 67 a 203 c-f 16 ENTRUST SC 6 fl oz/a ACE 0 a 0.3 a 5.3 ef 25 a 64 c-f 41 a 36 a 170 def V-10433 11 fl oz/a BDF 17 ENTRUST SC 6 fl oz/a ABCDEF 0.3 a 0.5 a 7.5 def 16 a 52 def 53 a 59 a 187 c-f 18 Ecotec 4 pt/a ABCDEF 0 a 1 a 25 ab 27 a 79 b-e 97 a 47 a 275 bcd 19 Delegate 4.5 oz/a ABCD 0 a 0.8 a 4 f 20 a 26 f 51 a 102 a 203 c-f 20 Delegate 6 oz/a ABCD 0 a 0.3 a 9.8 def 25 a 27 ef 42 a 62 a 165 ef 21 Exirel 13.5 fl oz/a ABCD 0 a 0.8 a 12.5 c-f 26 a 67 c-f 54 a 98 a 257 b-f 22 Warrior II 2.56 fl oz/a ABCD 0 a 0 a 11.3 c-f 11 a 41 def 45 a 51 a 159 f 23 Untreated 0 a 1.5 a 28.3 a 30 a 51 def 80 a 79 a 269 b-e LSD P=.05 0.21 2.29 11.22 35.97 52.13 47.08 60.31 109.86 Standard Deviation 0.15 1.62 7.95 25.48 36.92 33.35 42.72 77.81 Treatment F 0.94 1.023 3.882 0.854 3.572 1.586 1.145 3.003 Treatment Prob(F) 0.5464 0.4509 0.0001 0.6503 0.0001 0.0776 0.3267 0.0003 Figure 1. SWD larvae population at 7 days after application B (7 DAB).
57
Spotted Wing Drosophila Population Control with Precision Guided Sterile Males: Proof-of- concept in Drosophila melanogaster. G. Alton President and COO; Agragene Inc.
The sterile insect technique (SIT) is an environmentally safe and proven technology to suppress wild populations. However, the conventional approach used since the 1950s requires stringent sex selection, precisely controlled irradiation of pupae and subsequent rearing and shipments of live adult insects to field sites. Thus, it is expensive and requires large scale factory production. As such, it is not a commercially viable approach to achieve insect birth control in specialty crop pests. To further advance its utility, a novel CRISPR-based technology termed “precision guided SIT” (pgSIT) is described. PgSIT mechanistically relies on a dominant genetic technology that enables simultaneous sexing and sterilization, facilitating the release of eggs into the environment ensuring only sterile adult males emerge. Importantly, for field applications, the release of eggs will eliminate burdens of manually sexing and sterilizing males, thereby reducing overall effort and increasing scalability. Spotted wing drosophila (Drosophila suzukii) is an economically important pest of blueberry, strawberry, blackberry, raspberry and cherry. Additionally, many other crops are also susceptible to damage by this pest. To demonstrate efficacy, we systematically engineer multiple pgSIT systems in Drosophila melanogaster, which is a highly related subspecies to spotted wing drosophila. These consistently give rise to 100% sterile males. Importantly, we demonstrate that pgSIT-generated males are fit and competitive vs. wild type males. Using mathematical models, we predict pgSIT will induce substantially greater population suppression than can be achieved by currently-available self-limiting suppression technologies. Agragene intends to commercialize this technology in spotted wing drosophila as part on an integrated pest management strategy initially in Oregon blueberry, raspberry and cherry fields.
58
PHYSIOLOGICAL EFFECT OF ERYTHRITOL FOR SPOTTED WING DROSOPHILA M-Y. Choi, J. C. Lee, USDA-ARS Horticultural Crops Research Unit 3420 NW Orchard Ave., Corvallis, OR 97330 [email protected], [email protected]
Spotted wing drosophila (SWD), Drosophila suzukii, is a widespread economic pest of most of small fruits including berry and cherry crops around the world. To avoid over use of chemical insecticides that is currently major option to control SWD, growers might need biological-based approaches as chemical alternatives. Sugars mixed in insecticides have been used to increase insecticidal effectiveness by acting as a phagostimulant, causing pests to ingest more insecticide. These sugars are mainly nutritive sugars including sucrose, not non-nutritive sugars. Recently, we found various combinations of erythritol, a non-nutritive sugar, having an insecticidal effect on SWD. The effects are the reduction of the fly longevity and fecundity under various sugar formulations. The study suggests potential physiological mode of actions on the fly are starvation from the feeding of non- metabolizable erythritol, and imbalance of osmotic pressure in the hemolymph and digestive organs in the fly.
59
FIELD TESTS OF ERYTHRITOL FOR SPOTTED WING DROSOPHILA J. C. Lee, Man-Yeon Choi USDA-ARS Horticultural Crops Research Unit 3420 NW Orchard Ave., Corvallis, OR 97330 [email protected] , [email protected]
Spotted wing drosophila (SWD), Drosophila suzukii, is a widespread economic pest of small fruits and cherries around the world. While this pest is often controlled by insecticides, growers have asked for biorational approaches that are conveniently applied and ‘soft’. Erythritol is a non-caloric sugar that is safe for human consumption but kills and reduces the fecundity of SWD. Previous lab and greenhouse cage studies have shown promise. We further tested the efficacy of a 2M erythritol: 0.5 M sucrose spray in an open greenhouse with potted blueberry plants, and in an experimental blueberry plot. Fewer SWD developed from sprayed blueberries compared to the controls when fruit were collected from an open field. Also, fewer eggs were laid on sprayed berries when flies were confined to clusters for 24 hours in the field.
60
ANTIMICROBIALS FOR SPOTTED WING DROSOPHILA CONTROL J. C. Lee, L. Komnenus USDA-ARS Horticultural Crops Research Unit 3420 NW Orchard Ave., Corvallis, OR 97330 [email protected] , [email protected]
Spotted wing drosophila (SWD), Drosophila suzukii, is a widespread economic pest of small fruits and cherries around the world. This pest is primarily controlled by chemical insecticides. Growers may also spray crops with anti-microbial products to sterilize fruit, and this is thought to help with controlling SWD. While it is known that SWD adults are attracted to yeast odors and yeast are an important component of their gut microflora, the effectiveness of these antimicrobials and how they affect SWD need to be documented. Therefore, we studied how two commercial products impacted the settling rates of adults on fruit, oviposition rates, and survivorship of eggs in fruit. Fewer male and female SWD settled on berries dipped in antimicrobials during a 2 h exposure period. There was no reduction in the number of eggs laid on berries treated with antimicrobials under no-choice. There was no reduction in the proportion of eggs that developed to adulthood from berries dipped in antimicrobials; these eggs were laid prior to dipping.
61
Preliminary results on the efficacy of plant volatiles in the biocontrol of the azalea lace bug K.V. Graham1 and J. Lee2 1Oregon State University, 2USDA-ARS Corvallis [email protected], [email protected]
The azalea lace bug, Stephanitis pyriodies (Tingidae) is a pest of azaleas and rhododendrons (Ericaceae) which are popular ornamental bushes used for landscaping across the US and in many other parts of the world. Oregon was the number one exporter of florist’s azalea last year. Presently systemic insecticides are the only reliable control since contact insecticides can’t reach neither the eggs, which are oviposited inside the leaf tissue and covered with a dark substance which hardens as it dries, nor the nymphs and adults which tend to hang out on the underside of the leaf. Our lab has shown green lacewing are effective predators of the azalea lace bug. The former can be purchased as larvae and tapped onto affected plants or in the form of an egg card. The aim of this project is to attract naturally occurring green lacewing (Chrysoperla plorabunda) to azalea lace bug infested bushes with synthetic plant volatiles. In a multifactorial study1, it was determined that a combination of compounds performed much better than single compounds in attracting green lacewings. Compounds for this study were chosen based on their performance, their attractiveness to males and females, and if they had increased oviposition in previous studies2.
Parameters analyzed included number of eggs per cm2, number of nymphs and adults, and number of predators on two separate CRD studies: one with potted rhododendrons, the other with landscape azaleas. Of these, only the number of eggs/cm2 on the potted rhododendrons was significantly different; a multiple comparison test showed the AA+PE+AP treatment was significantly different from AA+PE+MeSA treatment and the control. Though not significantly different, there was a steady upward trend for predatory hemipterans and predatory mites whereas green lacewing numbers were very low. The MeSA+AA+PAA did not yield significant differences, thus is not included in the chart below.
The lack of effect in our study may be explained by a recently published study3. Compounds used as the attractants in our study (acetophenone, methyl salicylate and phenyl acetate) showed low 62
binding affinity for the olfactory binding proteins in Chrysoperla sinica (CsinOBPs). According to the authors, if compounds do not have a binding affinity for an insect predator’s OBPs, they would
not be attracted to them. Reportedly, the CsinOBPs exhibited antenna-enriched expression patterns like those of another lacewing species, C. pallens. Assuming C. plorabunda has a similar expression pattern as C. sinica and C. pallens, compounds better suited for a lure would be those which showed high binding affinity such as cis-3-hexenyl butyrate, farnesol and 2-pentadecanone or (−)-trans- caryophyllene, β-caryophyllene, (E)-β-farnesene, farnesol, and 2-hexyl-1-decanol.
1Jones, V.P., D. R. Horton, N.J. Mills, T.R. Unruh, C.C. Baker, T. D. Melton, E. Milickzy, S. A. Steffan, P.W. Shearer, K.G. Amarasekare. 2016. Evaluating plant volatiles for monitoring natural enemies in apple, pear and walnut orchards. Biological Control 102: 53-65. 2Koczor, S., Szentkirályi, F., Fekete, Z. and Tóth, M., 2017. Smells good, feels good: oviposition of Chrysoperla carnea-complex lacewings can be concentrated locally in the field with a combination of appropriate olfactory and tactile stimuli. Journal of Pest Science 90(1): 311-317. 3Li, Z.Q., Zhang, S., Cai, X.M., Luo, J.Y., Dong, S.L., Cui, J.J. and Chen, Z.M., 2018. Distinct binding affinities of odorant-binding proteins from the natural predator Chrysoperla sinica suggest different strategies to hunt prey. Journal of insect physiology, 111, pp.25-31.
63
SECTION VII Pests of Turf and Ornamentals
64
Survey of Spider Mites and Natural Enemies on ‘Autumn Blaze’ Maple in Oregon Nursery Production
Robin Rosetta Oregon State University
15210 NE Miley Rd, Aurora, OR 97002-9543
Oregon is the largest producer of shade trees in the nation. One of the most popular trees grown in Oregon shade tree production is Autumn Blaze® maple, Acer x freemanii Autumn Blaze®. Shade tree nurseries commonly manage insect pests such as lygus bugs, Lygus hesperus which feed on the new terminal growth on maples. The lygus bug feeding damages or kills the maple terminal, requiring additional labor to reinstitute another terminal to meet stringent quality demands for trees with strong central leaders. Most of the insecticides used for lygus bugs on maples are broad spectrum pyrethroids or organophophates. In the spring of 2018, a nursery contacted Oregon State University Extension concerned about outbreaks of spider mites caused by insecticides used to control lygus bugs on the growing tips of the maple shade trees. In order to better understand the timing and ecology of the spider mite outbreaks on these maples, a survey was implemented to determine the secondary pest complex, with a focus on spider mites and potential natural enemies, on Autumn Blaze® maple grown in a commercial nursery in Oregon during the late spring and summer of 2018,
Methods:
The survey was conducted in a field of Autumn Blaze® maple located at a commercial shade tree nursery in Marion County, Oregon. Three blocks (Block 1, Block 2, Block3) of Autumn Blaze® maples were sampled to determine populations of two-spotted spider mites (TSSM), Tetranychus urticae; aphids (various species treated as one); green lacewings, (unidentified species); lady beetles (various species treated as one); spider-mite destroyer, Stethorus sp.; small arboreal beetles, possibly carabids (unidentified species); whiteflies (unidentified species); predatory mites (unidentified species); and spiders (unidentified species). From May 20, 2018 through August 21, 2018, twenty trees from each block were randomly sampled weekly with one lower leaf removed and the leaf underside assessed for the above species using an OptiVisor (Forestry Supplies).
On June 26, an unfamiliar spider mite was found during field sampling. Samples were collected and photographed using a stereo microscope (Leica microscope using Olympus Camedia camera). The mites in the images were tentatively identified as maple spider mites (MSM), Oligonychus aceris, and sampling for this spider mite was added to the survey. Specimens were collected at two additional nursery sites and sent to the Oregon Department of Agriculture for confirmation.
A tiny beetle, possibly a carabid, was sometimes noted searching on maple leaves. The behavior appeared to be predatory so assessment of this, as yet unidentified, beetle was added to the survey.
65
Results
Small numbers of TSSM were found in blocks 1 & 3 in late May but not found in block 2 until July 3. Two-spotted spider mites populations peaked in block 1 on July 9 with 68 mites per 20 leaves or 3.4 mites/leaf average. TSSM peaked in block 2 on July 19 with 18 mites on 20 leaves or 0.9 mites/leaf average, and TSSM reached a high of 136 mites per 20 leaves or 6.8 mites/leaf average in block 3 on July 3.
The mite samples sent to the ODA were confirmed by Josh Vlach as maple spider mite, a new species detection for Oregon. While MSM was found only in one block, 3, on June 26, it was found in the two other blocks, 1 & 2, by July 3. MSM continued to be found in every block during each sampling date except July 31.
Maple spider mite populations varied between the three blocks. In block 1, MSM nearly equally cohabited the maples with TSSM. The maple spider mite population had three peaks, the highest with 90 mites per 20 leaf samples or 5 mites/leaf average on August 21, the last sample date for the trial. In block 2, the MSM dominated compared to very low levels of TSSM with a bi-modal distribution. In block two, MSM populations were highest on August 21, with 212 mites per 20 leaves or 10.6 mites/leaf average. In block 3, MSM populations remained at far lower levels, with the highest peak of 47 mites per 20 leaves or 2.35 mites/leaf average. Sampling was discontinued early (July 31) in this plot due to forest fire smoke pollution and time limitations on the following sample dates.
Aphids are an important alternate prey source for generalist predators and were evident from the beginning of sampling on May 29 but were absent by June 26 in blocks 1 & 2 and by July 3 in block 3. There was evidence of aphid parasitoids (mummies) and entomopathogenic fungi (dead diseased aphids) on sample leaves.
Green lacewing sightings around the plots and green lacewing eggs were found in all blocks sporadically from the first two weeks of sampling but began to increase in July. Green lacewing eggs were the most abundant natural enemies on our sample units through the end of the summer sampling period. Green lacewing eggs peaked in block 1 on July 17 with 17 eggs per 20 leaves or an average of 0.85 eggs/leaf. The eggs were found in that block on each sampling date thereafter. Green lacewing eggs peaked in block two on August 8 with 20 green lacewing eggs per 20 leaves or an average of 1.0 egg/leaf. The peak green lacewing egg population for block 3 was 11 eggs per 20 leaves or 0.55 eggs/leaf on July 17.
Spider mite destroyer, Stethorus sp., is a specialist predator on spider mites. Both adult and larval stages of Stethorus lady beetles were found sporadically in all blocks but generally increased mid-late July. They were not found by the last sample date on Aug. 21.
Predatory mites and their eggs were sighted as early as June 26 in block 3 but were found in blocks 1 & 2 by July 9. Their numbers remained relatively low, with a peak of 6 predatory mites per 20 leaves in block 1 on July 17. No predatory mites were found by the last sample date on Aug. 21.
The unidentified beetle, thought to be a carabid, was first noted on sample leaves on June 19 in all blocks. The beetle was not found on the sample unit leaves by July 31.
Only 3 spiders were found on sample leaves throughout the season and only in block 1. Only one lady beetle, that was not a Stethorus sp., was found during sampling. Whiteflies, potentially alternate prey for generalist predators, were present sporadically throughout the season but in very low numbers.
Pesticide application information will be added to this survey and further statistical analysis is ongoing. A second year of survey is planned for this system with the addition of sampling for the primary terminal pest. It was apparent during the 2018 system that the dominant terminal pest of maples during this survey was not lygus, which was present in low numbers, but was thrips, as many more terminals showed the 66
presence and damage of thrips. Tolerance for both pests is similarly low, but the management options for thrips includes a larger array of more selective insecticides compared to those insecticides used for lygus. Enhancing our knowledge of the activity of both the primary or key terminal pests and the secondary pests, we may be able to help growers choose more selective insecticides applied with better timing to increase management of key pests, mitigate disruption of natural enemies present in maple production, and reduce secondary pest outbreaks.
120 Autumn Blaze® maple Block 1 100 80 60 40 20 0
2-spot sm maple sm aphids gr lwg egg lady beetl Stethorus Carabid whitefly pred mite spider
Fig. 1. Survey of Secondary Insects and Mite Pests and Natural Enemies on Autumn Blaze® maple in Block 1 of a Commercial Nursery Production in Oregon.
67
SECTION VIII New & Current Product Development
68
CID BIO-SCIENCE, INC.: A REVIEW OF INSTRUMENTATION AVAILABLE TO EVALUATE PLANT RESPONSE TO INSECT DAMAGE K.Tso CID Bio-Science, Inc. 1554 NE 3rd Ave, Camas, WA 98607 [email protected]
Who We Are CID Bio-Science, Inc., has been designing instruments for agricultural and environmental plant research for over 28 years. Our company was established in 1989 with the introduction of our state-of-the-art handheld photosynthesis system. Since then we have expanded to develop 13 instruments to measure plant function, continuously employing new innovations and technologies. Headquartered in the Pacific Northwest of the United States, CID instruments are represented by distributors in 44 countries. In 2012 we founded subsidiary company, Felix Instruments - Applied Food Science, to put our decades of experience engineering plant science tools to work for the commercial agriculture sector. Focusing on pre- and postharvest applications, Felix Instruments helps fresh market professionals maximize the value of their products with our line of Gas Analyzers and NIR Produce Quality Meter.
The CI-110 Plant Canopy Imager The Plant Canopy Imager CI-110 captures wide-angle canopy images while estimating Leaf Area Index (LAI) and measuring Photosynthetically Active Radiation (PAR) levels. Images live- update on the built-in capacitive monitor, providing instant data for verification and analysis using integrated software in the field under any daylight conditions. User-selected zenith and azimuthal divisions allow investigation of any canopy sectors desired, and the instrument’s light-weight design makes it convenient for canopy imaging in any location. Now with updated GPS accuracy with access to four different satellite constellations, and the ability to interchange lens filters over the camera for more specific measurements.
CI-600 and 602 In-Situ Root Imagers Observing a root system throughout a plant’s life cycle is key to understanding overall plant behavior and health, and to improving crop performance. The CI-600 is a minirhizotron that can capture non-destructive, high-resolution, digital images of living roots in soil over multiple growing seasons. Durable and lightweight, the CI-600 is a portable minirhizotron that is easy to transport to any field location and can be used in sites with root tubes across a range of treatments or conditions. Our free root analysis software, RootSnap!, quickly and easily calculates parameters including root length, area, volume, diameter & branching angle. 69
Felix Instruments Gas Analyzers Ethylene production in plants is a common response to stress, such as that caused by insect damage. Felix Instruments offers a wide range of gas analyzers to measure levels of ethylene, CO2 and O2 in real time. Our handheld gas analyzers offer an intuitive user interface, making it simple to operate right out of the box. A built-in data logger stores thousands of data points and conveniently communicates data through USB to a PC or tablet for later analysis.
Brief Overview of Other CID Bio-Science Tools CID Bio-Science, Inc. makes other instruments that you may find useful to your work including the: CI-202 Portable Laser Leaf Area Meter; CI-203 Handheld Laser Leaf Area Meter; CI- 340 Handheld Photosynthesis System; and the CI-710 Mini Leaf Spectrometer.
70
SECTION IX Extension & Consulting: Updates and Notes from the Field
71
REGIONAL MONITORING FOR TRUE ARMYWORM
J. Green1, T. Thomson2, N. Anderson3, C. Bouska1, and W. Jessie3 1OSU Dept. of Horticulture 4017 Ag. & Life Sci. Bldg., Corvallis, OR. 97331 2Northwest Agricultural Consulting Dallas, OR. 97338 3OSU Dept. of Crop and Soil Science / OSU Extension 3017 Ag. & Life Sci. Bldg., Corvallis, OR. 97331
[email protected]; [email protected]; [email protected]
Cutworms and armyworms have extremely wide host ranges and have been identified as a medium to high priority pest by various commodity groups including small fruit, grass and forage, grain, vegetable, cranberry, and mint.
Increasing concern of armyworms in Oregon crops spurred area consultants and Extension personnel to perform regional surveys. A more concerted effort is planned for next year. Without predictive tools (monitoring of adult moths, crop scouting, and detection of larvae), armyworm attacks are only noticed too late, when the most severe damage has already been done.
True armyworm outbreaks are cyclical, and tend to occur in the PNW every 7 to 15 years. Because this species is a long-range migrant, patterns of migration are currently under investigation2 to provide insight that may aid predictive efforts and therefore control of this damaging pest. We are working with those researchers to try to determine geographic sources of true armyworms in Oregon at varying times of the year.
In warmer regions, Mythimna unipuncta (MUNI) overwinters as a partially mature larvae, but phenologic trends in the PNW are unknown. Flight activity peaks in late September, and it has been suggested that adult moths can overwinter in the PNW. Periodic field scouting for larvae occurred in each monitored region, and no abnormally high levels nor outbreaks were noted. This is consistent with reports from growers who, while very concerned about armyworm based on prior years, did not seem to experience abnormal damage from May-Sept 2018. There was, however, increased pressure from winter cutworm, Noctua pronuba, in grass seed and mint from Nov - current.
COOS and CURRY COUNTIES – An OSU Extension agent set and managed 25 baited bucket traps that were placed near pastures throughout Coos and Curry counties and monitored from June to August. The peak trap catch was ~ 7 moths/day. These baseline data obtained will be very useful for trap efforts planned for 2019.
72
TILLAMOOK COUNTY – Baited bucket traps were set at fifteen locations near pastures and dairy facilities by an independent consultant. From 15 May through the 19 Sept collection, all 15 sites were operational. From late September through 23 October, 6 sites were monitored, and 5 of those sites were monitored from 31 October through the end of the trapping season. In general, three activity peaks were noted in 2018. Three generations are considered normal for this species; up to five generations have been observed in Kentucky, two in Western Canada.
1 2 3 4 5 7 8 9 10 11 12 13 14 15 6
5
4
3
MUNI MUNI adults/day 2
1
0
Figure 3. Activity of true armyworm moths (Mythimna unipuncta, MUNI), as measured by baited bucket traps at 15 sites in Tillamook County, OR. May 15 – Dec 6, 2018. Pheromone lure changes are indicated by arrows. LINN COUNTY – A preliminary trapping program for true armyworm was performed by OSU Extension faculty in Linn County; it consisted of 6 baited bucket traps set in perennial ryegrass fields and monitored from 20 Jun to 30 July. Activity peaked on 23 Jul, with an average maximum catch of 3 moths per day. Although true armyworm is not a species traditionally measured by the VegNet program, MUNI was tracked at a few locations as a non-target catch (if detected in bertha armyworm pheromone traps). POLK COUNTY – Armyworms are a big concern due to the large acreage of grass seed grown in the area. Baited pheromone traps (n=8) were set in four different areas and monitored from 30 May to 6 Jul. The average trap count early in the season was skewed by a particularly high catch at one site near Forest Grove, OR (11 moths/day on 1 Jun). References – 1. Breeland, S.G., Biological studies on the armyworm, Pseudaletia unipuncta (Haworth). Tennessee (Lepidoptera: Noctuidae). J. Tenn. Acad. Sci, 1958. 33: p. 263-347. 2. Doward, K., Migratory movements of the true armyworm (Mythimna unipuncta)(Haworth): An investigation using naturally occurring stable hydrogen isotopes, M.S. Thesis in Biology. 2018, Univ. of Western Ontario. 73
Attendee List for 78th Pacific Northwest Insect Management Conference
January 07, 2019 Portland, Oregon Attendee List for 78th PacificParticipants: Northwest 39 Insect Management Conference
January 07, 2019 Portland, Oregon Participants: 39 Nino Adams Rich Affeldt Seung-Joon Ahn Phone: Phone: 5036402313 Central Oregon Seeds, Inc. 5417384030 [email protected] Phone: 541-475-7231 [email protected] [email protected]
Gordon Alton Ross Benedict Rachel Blood Phone: 8583358120 Collins Agricultural Consultants Phone: 2693700008 [email protected] Phone: 5037813374 [email protected] [email protected]
J Reed Britt Ron Britt Priyadarshini Chakrabarti Basu Phone: Phone: 5099669681 Phone: 5099669681 5412860804 [email protected] [email protected] priyadarshini.chakrabarti@oregonstate. edu
Man-yeon Choi Chris Clemens Sean Collins Phone: 541-738-4030 Phone: 509-308-5599 Phone: 5038607458 [email protected] [email protected] [email protected]
Andrew Colton Phone: 541 Stephen Flanagan Gracie Galindo Phone: 9081149 UC Davis- IR4 Program 5417384110 [email protected] Phone: 5416883155 [email protected] [email protected]
Beverly Gerdeman Jessica Green Phone: Chris Hedstrom Phone: Phone: 360-848-6153 5417373464 5039864654 [email protected] [email protected] [email protected]
1 of 3 74
Beverly Gerdeman Jessica Green Phone: Chris Hedstrom Phone: Phone: 360-848-6153 5417373464 5039864654 [email protected] [email protected] [email protected]
Jess Holcomb Phone: Matt Klaus Matthew Klein Phone: 5094139633 Phone: 5099859916 3025989666 [email protected] [email protected] [email protected]
Alan Knight Lauren Komnenus Phone: Amanda Koppel Phone: 509- Phone: 509-454-5657 5417384110 868-6298 [email protected] [email protected] [email protected]
Jana Lee Dani Lightle Chris Looney Phone: 5417384110 Phone: 5308651153 Phone: 360-902-1976 [email protected] [email protected] [email protected]
Gary Melchior Phone: Jef Nichols Amanda Ohrn 5095204779 Phone: 5099691780 Phone: 503-986-4640 [email protected] [email protected] [email protected]
Colin Park Grant Pynes Chris Rechner Phone: Phone: 503-351-7143 Phone: 5413256889 2178365334 [email protected] [email protected] [email protected]
Robin Rosetta Katerina Velasco Graham Douglas Walsh Phone: 503-678-1264 Phone: 5417384110 Phone: 5097862226 [email protected] [email protected] [email protected]
Tim Waters John Weber Jafe Weems Phone: 5095453511 Phone: 5413251352 Phone: 5156648426 [email protected] [email protected] [email protected]
75