Sequential sampling plans for western flower thrips (Thysanoptera: Thripidae) on greenhouse cucumbers

Area of Science:

• Agricultural Entomology
• Pest Management
• Horticulture

Background:

• Effective management of western flower thrips (Frankliniella occidentalis) in greenhouse cucumbers requires reliable sampling methods.
• Adoption of economic injury levels and thresholds by growers is hindered by the lack of cost-effective sampling programs.

Purpose of the Study:

• To develop two sequential sampling plans for western flower thrips (F. occidentalis) on greenhouse cucumbers.
• To provide tools for estimating pest density and classifying population levels relative to economic thresholds.

Main Methods:

• Development of a fixed-precision sequential sampling plan for estimating F. occidentalis adult density.
• Development of a sequential sampling plan for classifying thrips population levels (below/above economic thresholds).
• Validation of both plans using resampling simulation on independent datasets.

Main Results:

• The fixed-precision plan accurately estimated F. occidentalis density across various population levels.
• The classification plan required fewer samples when densities were far from the economic threshold.
• Simulation results informed recommendations for appropriate precision levels based on population density.

Conclusions:

• Sequential sampling plans offer efficient methods for managing western flower thrips in greenhouse cucumber production.
• A combination of fixed-precision and classification sampling plans is recommended for optimal pest management decisions.
• These tools can support grower adoption of integrated pest management strategies.