Primary screening and application of repellent plant volatiles to control tea leafhopper, Empoasca onukii Matsuda

Abstract

BACKGROUND The tea leafhopper, Empoasca onukii Matsuda (Hemiptera: Cicadellidae), is a major pest of tea plants in China. Here, we evaluated the repellent properties of eight volatile chemicals alone and in various combinations as tools for the management of this pest in tea gardens. These chemicals were from the Alliaceae and other aromatic plants, and are known to repel various insect species. RESULTS Among the eight volatile compounds, dimethyl disulfide (DMDS), 1,8‐cineole and allyl methyl sulfide were significantly repellent towards E. onukii adults. DMDS and 1,8‐cineole were mixed to formulate a binary repellent. Under field conditions, spraying and slow‐release applications of the mixture significantly decreased the density of E. onukii adults. The repelling effect after spraying was very short, only ∼ 2 days, but the slow‐release mixture had a longer term repelling effect on E. onukii adults. High emission of the slow‐release mixture, which was achieved by increasing the number of slow‐release bottles, had a stronger repellent effect than low emission. Moreover, when the amount emitted was sufficient, the slow‐release mixture significantly decreased the number of leafhopper nymphs in a treated tea‐plant line, and significantly decreased the number of leafhopper adults and nymphs in a tea‐plant line adjacent to the treated area. CONCLUSION This study demonstrates the repellent action of a mixture of DMDS and 1,8‐cineole applied by a slow‐release method against E. onukii in a tea plantation. This mixture has potential applications in integrated pest management schemes. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Electrophysiological and Behavioral Responses of Plutella xylostella (Lepidoptera: Plutellidae) to Volatiles from a Non-host Plant, Geranium, Pelargonium × hortorum (Geraniaceae)

“…The results of the net room trails were used to test the repellent effect of the slow-release blend-2 in the field as previously described with a few modifications. 33 The experiment was conducted in the field from July to October 2020. The DBM population density and number of eggs were confirmed before the field trial.…”

Field application of tea volatiles mediating host selection of Aleurocanthus spiniferus

“…The accumulating evidence on the C6-volatile (Z)-3hexenol supports its crucial role in mediating indirect defense responses in plants. Tea The application of plant-derived semiochemicals to control tea pests has been widely reported, such as the application of a mixture of dimethyl disul de (DMDS) and 1,8-eucalyptin to repel E. onukii in tea elds and the application of (E)-2-hexenal, (Z)-3-hexenol, (Z)-hexenyl acetate, (E)-ocimene, linalool, and geraniol as E. onukii attractants (Chen et al 2019;Cai et al 2020). Field trials had shown a signi cant improvement in trapping e ciency when combined with yellow sticky traps.…”

“…Some speci c compounds have been successfully used for population monitoring and integrated pest management (Li et al 2014;Chen et al 2019; Wang et al 2020). A binary repellent containing DMDS and 1,8-cineole, for instance, applied by a slow-release method against Empoasca onukii in a tea plantation (Cai et al 2020).…”

Characterization of Volatile Compounds from Tea Plants (Camellia sinensis (L.) Kuntze) and the Effect of Identified Compounds on Empoasca flavescens Behavior

“…The volatile compounds were dissolved in liquid paraffin (1%), and 20 µL of solution or paraffin alone was applied to a filter paper square (1 × 1 cm). One arm of the olfactometer [6,9] received a filter paper with the sample and the other arm received paraffin only. Charcoal and humidified, filtered air was driven into each tube with a vacuum pump.…”