• Korean journal of applied entomology
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• v.62 no.4
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• pp.245-253
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• 2023

A control technique using mass-trapping was developed against thrips infesting hot peppers cultivating in greenhouses. It was essential to develop effective lure(s) attracting thrips for the control technique. Especially, mass-trapping using aggregation pheromone (AP) of the thrips was not much effective in open field cultivating hot peppers. This study aimed to develop a new lure to enhance the attractiveness of AP-based mass-trapping. In addition, this study was designed to investigate the decrease of attractiveness of the AP-based mass-trapping in the open field conditions. Methyl isonicotinate (MIN) as a new lure was assessed by the laboratory olfactometry and showed its attractiveness to thrips and its mixture effect with AP to attract the thrips. These results led us to test the AP+MIN mixture in the open field conditions cultivating hot peppers. The mixture significantly enhanced the mass-trapping efficacy in the open field conditions. Especially, the significant increase of the captured numbers was found in the western flower thrips, Frankliniella occidentalis. Furthermore, the increase of the AP concentration in the mass-trapping significantly increased the captured numbers in F. occidentalis and other thrips occurring in the hot pepper field. This study demonstrated the difference in the AP-based mass-trapping efficacy of the thrips between greenhouse and open field conditions. It also showed the increase of mass-trapping efficacy by increasing AP concentration in the trap. Especially, this study proposes a high efficient mass-trapping technology by the addition of MIN to AP especially against F. occidentalis.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.369-377
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• 2021

Mass trapping of the western flower thrips, Frankliniella occidentalis, has been considered as an option to control this pest. This study applied the commercial lures to the hot pepper-cultivating greenhouses and assessed the enhancement of the attracting efficiency by adding to sticky traps. There was no color difference in the attracting efficiency between blue and yellow sticky traps. However, the installation position of the traps was crucial in the greenhouses. The more thrips were captured within host cropping area than outside areas of the crop. In vertical trap position, it was the most optimal to install the traps at the crop crown. Using these installation parameters, the yellow sticky traps captured approximately 1% population of the thrips. To enhance the trapping efficiency, the commercial lures containing aggregation pheromone or 4-methoxybenzaldehyde were added to the yellow sticky traps. However, these commercial lures did not significantly enhance the trapping efficiency compared to the yellow sticky trap alone. In contrast, Y-tube olfactometry assays confirmed the high efficiency of the aggregation pheromone or another plant volatile (methyl isonicotinate) to attract the thrips. Interestingly, these lure components had lower attracting efficiencies compared to the hot pepper flowers. The high attractive efficiency of the flowers was supported by the observation that the commercial lure was effective to enhance the trapping efficiency of the yellow sticky trap against F. occidentalis in Welsh onion (Allium fistulosum) field without any flowers. This study indicates the limitation of the commercial lures in application to hot pepper fields for the mass trapping of F. occidentalis. It also suggests active volatile component(s) from hot pepper flowers to attract F. occidentalis.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2341-2344
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• 2009

Metallacyclodimers, [Ag(OTf)($L1)]_2$ and [Ag($L2)]_2(OTf)_2$ (L1 = 1,3-dibromo-2,2-bis[(isonicotinoyloxy)methyl] propane; L2 = 2,5-dimethyl-2,5-bis(isonicotinoyloxy)hexane) were constructed and characterized. The crystal structure of [Ag(OTf)($L1)]_2$ reveals a 32-membered cyclodimer, whereas that of [Ag($L2)]_2(OTf)_2$ shows a linked 34-membered cyclodimer chain via intercyclic argentophilic (Ag…Ag) interactions. [Ag(OTf)($(L1)]_2$ affords “intramolecular $\pi-\pi$ interaction cyclodimer” whereas [Ag($L2)]_2(OTf)_2$ produces a racemic mixture of “twisted cyclodimer”. Ring-conformation of the cyclodimers was affected via the competition of electrostatic interaction and argentophilic interaction.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.209-218
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• 2019

This study was conducted to develop a technology for environmentally friendly control of sweet-potato whitefly, Bemisia tabaci, by controlling their behavior using a push-pull strategy in a tomato greenhouse. B. tabaci was attracted the most by yellow color, light source of 520 nm, whereas it avoided the complex light treatment of 450 + 660 nm. The two natural enemies of B. tabaci, Cyrtopeltis tenuis and Orius laevigatus, were attracted the most by 520 nm light source. B. tabaci was repelled by the volatile organic compounds ocimene and carvacrol and was the most attracted by methyl isonicotinate. When buckwheat was added into the tomato greenhouse, the density of C. tenuis was maintained at about 16 times higher than when untreated for 15 days. As a result of the combined treatment of push-pull strategy, the density per trap of B. tabaci was three times lower than when no treatment was applied, and the control of this pest increased with time and reached up to 68.7%.