UC IPM Online UC ANR home page UC IPM home page

UC IPM Home

SKIP navigation

 

Research and IPM

Grants Programs: Projects Database

Project description

Development of Sampling Procedures for Western Flower Thrips, Frankliniella occidentalis, in Greenhouse Flower Production. (96DS029)
Program UC IPM competitive research grants program
Principal
investigators
M.P. Parrella, Entomology, UC Davis
B.C. Murphy, Entomology, UC Davis
Host/habitat Greenhouse Crops; Flowers; Roses; Chrysanthemums
Pest Thrips
Discipline Entomology
Beneficial
organism
Unspecified
Review
panel
Decision Support
Start year (duration)  1996 (Two Years)
Objectives Determine the within- and between-plant distribution of western flower thrips on roses and chrysanthemums for common cultivars during the growing season and determine the optimal sample unit for estimating western flower thrips (WFT) abundance.

Develop and evaluate a practical, grower-oriented sampling procedure using sticky cards, plant samples, or a combination of the two for monitoring WFT to determine the need for control measures.

Estimate the relationship between WFT density on plants and the degree of feeding injury on foliage and flowers.

Verify effectiveness of the sampling procedures under commercial greenhouse conditions.

End-year
progress
During 1997 we completed all major objectives for WFT in fresh cut roses. Spatial distribution data for WTF were obtained from five commercial rose greenhouses in three regions (San Mateo, Monterey, and Santa Barbara counties) over the past two years. Data were used to quantify and assess the within-plant and between-plant distribution of WFT. We also determined a high degree of correlation existed between WFT captured on blue and yellow sticky cards and WFT density in roses demonstrating the potential for a sticky card monitoring procedure. Preliminary sample size estimates for estimating WFT abundance were generated for both a plant and a sticky card monitoring program. Sample size estimates showed development of a plant and/or sticky card monitoring program is feasible and likely cost effective. We also successfully estimated the relationship between WFT density in roses and the degree of feeding damage to foliage and flowers and developed preliminary estimates between WFT density and the proportion of the rose crop showing feeding injury. These results indicate development of a quantitative and meaningful economic and action thresholds for roses is feasible. Work is progressing to develop practical, grower-oriented sampling procedures and action guidelines in roses.

Completion of the objectives for chrysanthemums has progressed more slowly. Preliminary data on the within- and between-plant distribution indicate WFT abundance using plant samples can be estimated cost effectively in mums. Data are still being analyzed for some of this work. The degree of variation found in chrysanthemum cultivars and growing practices, in addition to interference from pesticides sprays, has required additional time and effort to obtain a sufficient database.

Top of page


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright 2018 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   web template revised: October 15, 2018 Contact webmaster.