Recipient Organization
WASHINGTON STATE UNIVERSITY
240 FRENCH ADMINISTRATION BLDG
PULLMAN,WA 99164-0001
Performing Department
(N/A)
Non Technical Summary
This project will help pear growers implement new tools for integrated pest management including scouting, thresholds, selective materials and phenology models. As a result we anticipate a reduction in the use of broad spectrum insecticides and insecticides considered of concern for adverse effects on wildlife, a reduction in spray costs and an increase in beneficial insect populations on at least 1500 acres in the pear growing regions of Washington and Oregon.
Animal Health Component
100%
Research Effort Categories
Basic
0%
Applied
100%
Developmental
0%
Goals / Objectives
Objective 1: Implement and Expand IPM Scouting Network (Extension)• 1a. Provide scouting services in cooperation with fruit warehouses and chemical distributors.• 1b. WSU will train and support scouts.• 1c. Scout 100 orchards per year.• 1d. Update and maintain scouting information distribution platform.Objective 2: Evaluate Application of a Pear Psylla Phenology Model for IPM (Research)• Measure pear psylla and natural enemy numbers in 7 IPM and 7 conventional orchards.Objective 3. Test Pear Psylla and Natural Enemy Thresholds (Extension)• 3a. Test the accuracy of natural enemy inaction thresholds: if natural enemy inaction thresholds are met do pear psylla populations remain under control.• 3b. Test the accuracy of pear psylla economic thresholds: If psylla populations are below economic thresholds (ET) do pest populations remain below economic injury levels (EIL)?• 3c. Test the accuracy of pear psylla population models during the second and third generation.Objective 4. Increase Grower Knowledge and Implementation of Pear IPM Techniques (Extension)• 4a. Stakeholder Advisory Group. Convene grower and consultant stakeholders annually to acquire feedback and refine objectives.• 4b. Pear Entomology Weekly. A weekly e-mailed public report of scouting data from Objective 2 shared alongside degree-day appropriate IPM guidelines and notifications of extension events.• 4c. Update IPM Guidelines and Factsheet. Washington State University's Pear Psylla Integrated Pest Management was recently published in 2022 (Nottingham et al. 2022) with phenology based insecticide recommendations and economic thresholds. After three years of IPM program implementation it will be updated with revisions to IPM guidelines.• 4d. Implement Publicly Available Scouting Phone Application. We will convert the recently elaborated Scouting Network platform created in Power BI into a downloadable phone application available for Iphone and Android.• 4e. Study circles. Two study circles will be hosted per year.Objective 5. Expand IPM toolbox to additional regions (Research)• Scout 3 IPM and 3 conventional orchards for natural enemies and psylla in Hood River Oregon region (PI Adams).• Scout 3 IPM and 3 conventional orchards for natural enemies and psylla in Yakima Valley Washington region (PI Schmidt).• Evaluate Phenology Model IPM using Hood River Oregon and Yakima Valley Washington data.• Evaluate psylla and natural enemy thresholds using Hood River Oregon and Yakima Valley Washington data.• Cooperate with area consultants to train scouts and provide scouting platform to Oregon and Yakima valley area consultants.
Project Methods
3.1 Objective 1:Obj 1a Provide scouting services in cooperation with fruit warehouses and chemical distributors: 2 full- time scouts will be funded by the proposal and the equivalent of 2 full-time scouts with industry support (industry supported scouts may scout fewer sites part time). Obj 1b WSU will train and support scouts: Scout training will include weekly trainings conducted on Monday mornings. Scouts will be trained in beat tray and leaf sampling, psylla and natural enemy identification, laboratory leaf brushing and pear psylla and mite counting. As natural enemies emerge over the course of the growing season, weekly training is critical to help scouts correctly identify new natural enemies as they occur. Weekly training also allows project staff and scouts to discuss season-specific modifications to scouting techniques. Obj 1c Scout 100 orchards per year: Plots will be scouted once per week from early April to early October using beat trays, leaf samples, and earwig traps. Within each plot, thirty samples of canopy dwelling arthropods will be collected using the beat tray method. Each beat tray sample (one 'tray') involves holding a 45 by 45 cm white sheet 30 to 45 cm underneath a horizontal branch and striking it three times with a stiff rubber stick to dislodge insects onto the tray, which are then counted. Branches selected for sampling are 1 to 2 m above ground and 1.5 to 4 cm in diameter. The number of pear psylla adults and natural enemies per beat tray are counted. Major natural enemies included in analysis are adult T. insidiosus, Aranae (spiders), Anthocoridae (minute pirate bugs), C. verbasci (common mullein bugs), Chrysopidae (green lacewings), Coccinellidae (ladybird beetles), D. brevis, Forficula auricularia (European earwig), Geocoridae (big-eyed bugs), Hemerobiidae (brown lacewings), and Nabidae (damsel bugs). Additionally, leaf samples will be taken to determine densities of pear psylla eggs and nymphs. One hundred leaves are collected from ten randomly selected trees distributed throughout each plot. Prior to the development of vegetative shoots (from bloom in April until about June), twenty-five fruiting spurs are collected from both the lower and upper canopies of each tree. Lower canopy leaves are selected with two to three leaves in the inner, middle, and outer sections of scaffold limbs 1.2 to 1.8 m from the ground. Upper canopy leaves are taken from two fruit clusters using an extendable pole pruner. During summer, leaves are selected from both fruit clusters and shoots. Collected leaves are kept cool and returned to the lab to be sampled using a leaf brusher (Leedom Enterprises). Leaves are run through two motorized brushes which dislodge arthropods onto a revolving glass plate, creating a composite sample of arthropods which are counted under a stereoscopic microscope (Burts 1988, Horton 1999). Arthropods collected from the leaves included pear psylla eggs, young pear psylla nymphs (instars 1-3), old pear psylla nymphs (instars 4-5), mummified pear psylla nymphs, mealybugs, European red mites, Panonychus ulmi; spider mites T. urticae, T. mcdanieli; and pear rust mites, Epitrimerus pyri (Nalepa). Obj 1d Update and Maintain Scouting Information Distribution Platform: The Scouting Network App is an application designed to integrate research generated by WSU, with scouting data collected in the pear orchards. The project group will transition the Microsoft Power Apps system to a downloadable App available for iPhone and Android.3.2 Objective 2: Scouting led by Orpet will be conducted at seven paired locations (where one site follows IPM guidelines, and the other uses conventional broad-spectrum insecticides) that were previously studied during 2022-2023. The research goals of Objective 2, in contrast to related scouting in Objective 1, require an experimental design to scientifically evaluate the IPM program with appropriate controls for comparisons. Paired sites will be adjacent or nearby each other, planted at similar times, and have similar cultivar mixes. Sampling will be conducted weekly with the same methods as in Objective 1. Results for each location (pest and natural enemy counts) will be shared publicly weekly in an online newsletter (Objective 4b). Fruit damage will be assessed for Bartlett and Anjou pears within a week of their commercial harvest by inspecting and rating 100 fruit per orchard for pear psylla marking and other insect pest damage such as codling moth. Data will also be used for validation of pest management thresholds (Objective 3).3.3 Objective 3. Obj 3a. Natural enemy inaction threshold validation: To address the hypothesis that when natural enemies are above the threshold proposed by DuPont et al. 2023, third-generation psylla young nymphs did not significantly increase, we will test over two consecutive seasons datasets the relationship between pear psylla densities at each life stage and natural enemy densities. To determine the impact of natural enemy populations thresholds, a linear regression of the population of young psylla nymphs between the beginning (PPDD = 2,575) and maximum of the third-generation near harvest (PPDD = 4,100) will be conducted for 2 categories where natural enemies are above or below identified thresholds. Obj 3b. Pear psylla ET and EIL validation: To test the association between pear psylla young nymphs and adults ET at both 1300 and 2600 PPDD with population levels that exceed the EIL late in the season, in each management system (e.g., conventional, organic, IPM) we will create a dataset organized in a contingency table to be suitable for association analysis. Obj 3c. Pear psylla population projection validation: Model validation will be assessed by comparing the mean absolute error (MAE) of the model compared to MAE of the 2023 and 2024 predictions. For the 2023 and 2024 dataset, the prediction error will be assessed by computing the MAE between the actual pear psylla counts with the predicted value of the model.3.4 Objective 4. Increase Grower Knowledge and Implementation of Pear IPM TechniquesObj 4a. Stakeholder Advisory Group: Project PIs will meet with stakeholders on an annual basis to gather feedback on the project and refine project objectives and procedures. Obj 4b. Pear Entomology Weekly: Scouting data from each site in Objective 2 will be shared publicly by e-mail alongside IPM management guidelines. Obj 4c. Update IPM Guidelines and Factsheet: Project PIs will update Nottingham et al. (2022) with revisions to integrated pest management guidelines based on new research and stakeholder feedback. Obj 4d. Implement Publicly Available Scouting Phone Application: This program will be adapted into a phone application that can be downloaded for iPhone or Android. Obj 4e. Study circles: Two study circles will be hosted per year. Each study circle meeting will include a 30 min presentation by a member of the research team and 2 hours of facilitated discussion. A meal break provides informal networking time.3.5 Objective 5. PIs Adams and Schmidt will recruit scouts. These scouts will participate in an annual Scout Training. Scouts in each region will assess pest and natural enemy populations using beat trays and leaf sampling weekly for 22 to 24 weeks (see methodology Obj1). Sampling will be conducted in 3 IPM and 3 Conventional orchards in each region. Scouts will input data using the Scouting Network Application the day of sampling by 4pm. The Scouting App will send data to participating grower and consultant at 4pm. Data will be shared with co-PI Orpet for Objective 2: Evaluate Application of a Pear Psylla Phenology Model for IPM. Data will be shared with co-PI DuPont for Objective 3: Test Pear Psylla and Natural Enemy Thresholds. PIs will gather feedback from participating growers/consultants on Scouting Application and utility of thresholds.