Related Experiment Video
Updated: Sep 11, 2025
Sampling for Estimating Frankliniella Species Flower Thrips and Orius Species Predators in Field Experiments
Published on: July 17, 2019
Optimized use of UV-B light to suppress Western flower thrips in controlled environment tomato crops
Christian Nansen1, Yugeng Zou1, Maria D Hernandez1
1Department of Entomology and Nematology, University of California, Davis, California, USA.
Background:
LEDs (light emitting diodes) are being deployed in controlled environment crop production systems to boost crop growth, manipulate pest behavior, improve performance of natural enemies, and directly suppress pest populations. In this study, seven UV-B (280-315 nm) LED treatments were applied to tomato plants (Solanum lycopersicum L.) (in hours): 1 = 0, 2 = 0.5, 3 = 1, 4 = 2, 5 = 4, 6 = 8, and 7 = 24. Hyperspectral imaging data were acquired and examined based on spectral indices. After initial evaluations, we focused on effects of 4 h exposure to UV-B on oviposition preference and egg hatching by Western flower thrips (WFT) [Frankliniella occidentalis (Pergande)].
Results:
Exposure to UV-B for 4 h elicited an optimal combination of bio-responses: (1) based on vegetation indices, tomato plants appeared to recover from initial UV-B induced stress, (2) preference bioassays showed tomato plants were preferred by ovipositing WFTs over untreated control plants, and (3) 4 h exposure to UV-B significantly suppressed hatching rates of WFT eggs laid in tomato plants, irrespectively of whether deployed at night or during the day and irrespectively of whether projected from top (to adaxial sides of leaves) or bottom (to abaxial sides of leaves).
Conclusion:
From a comprehensive combination of plant and pest experiments, our results provide strong support for claims about 4 h exposure to UV-B possessing considerable potential as a pest management tactic. Results from this study support claims that pest management practices in controlled environment production systems may be more effective when deployed at night. This study is part of ongoing efforts to promote integration of innovative technologies to maximize both performance and sustainability of pest management strategies of vegetable and ornamental crops in controlled environments. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
