• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.241-246
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• 2010

Field experiments were carried out to establish economic threshold for com borer (Ostrinia furnacalis (Guen$\'{e}$e)) on waxy com plants by examining the number of adult insects caught in pheromone traps and the injury levels of waxy com which were artificially controlled. Adult com borers were lured into the pheromone traps during the whole growth period in five areas in Gangwon province including Chuncheon. The number of com borers trapped was the greatest in Chuncheon followed by Cheolwon and Hongcheon, and the same trend was observed for injury level of waxy com. Based on marketable yield data of waxy com plants related to the artificially-controlled injury levels at tassel stage, spray threshold was determined as the injury level of 11~15%, where the injury of com plants exceeded the economically admitting level.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.22-27
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• 2022

The attraction effects of light emitting diode (LED) trap to Spodoptera exigua and Spodoptera litura adults were evaluated in greenhouse and compared with those of no light trap, which is typical used in commercial trap. At this time, in order to attract these two species of moths, sex pheromone traps were installed at the top side according to the degree of tomato growth inside the tomato cultivation greenhouse around the LED trap. In addition, two types of light-emitting traps (420 nm, 470 nm) were installed in the greenhouse at 1/40 m², respectively. Also two sex pheromone were installed inside of the greenhouse according to the height of the tomato plants. 10 days later, Blue-light trap(BLB, 470 nm wavelength) was 3.1-3.5 times more attractive than Violet-light trap(VLB, 420 nm wavelength) in S. exigua (105.6 ± 7.3) and S. litura (42.0 ± 3.1) respectively, whereas the no-light trap was little attractive to S. exigua (33.7 ± 2.8) and S. litura (12.0 ± 1.5). On the other hand, after the installation of the sex pheromone trap and the LED trap, there was no damage to S. litura (Fabricius) and S. exigua in the pesticide-free area, indicating a high possibility of control. At this time, the operating cost of the two types of LED traps was 80 won/m² per unit area, and it was confirmed that both types of moths could be controlled. In addition, as a result of confirming the number of two types of moths caught in the sexual pheromone trap and two types of LED traps after 4 months, it was judged that eco-friendly control was possible as more than 373 moths/trap were attracted to the two types of moths.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.417-421
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• 2009

Monitoring was conducted to investigate the occurrence of Grapholita dimorpha Komai in Korean apple orchards using sex pheromone traps. G. dimorpa showed four peaks per year: early May, from late June to early July, from late July to mid August, and from late August to September. After adult emergence of the over-wintered G. dimorpha, G. dimorpha catches was decreased significantly and increased again after July. In G. molesta traps, G. molesta and G. dimorpha were trapped by 98.8 and 1.2%, respectively. Conversely in G. dimorpha traps, G. dimorpha and G. molesta were trapped by 99.7 and 0.3%, respectively. The 30.6% of the moths from the damaged apple fruits were G. dimorpha. This is the first report on G. dimorpha in apple orchards in Korea.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.67-72
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• 2009

The kairomonal activity of the aggregation pheromones of Riptortus clavatus for the egg parasitoid, Gryon japonicum, were investigated in soybean field. The parasitism rate of G. japonicum gradually decreased when the distances between pheromone traps and egg sites were increased from 0 to 15 m. The active distance of pheromone source for parasitoid attraction was estimated to be ca. 15 m. Under field conditions, the parasitoid wasp population peaked during the late August and early September, and the parasitism rate increased when the number of pheromone traps was increased from one to three per $165\;m^2$. However, insecticide-treated plots, the level of parasitism recorded is relatively low. Sex ratios in field populations of G. japonicum were female-biased.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.207-213
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• 2012

The cryptic mealybug, Pseudococcus cryptus, has been increasingly damaging citrus, particularly those plants grown in plastic greenhouses. This study was conducted to monitor the seasonal phenology of adult male cryptic mealybugs and to determine the timing for control using a sex pheromone trap. Adult males responded to a synthetic sex pheromone and trap color. An increasing number of males were attracted to the traps with increasing concentrations of sex pheromone up to 5 mg. The males occurred annually four times and had three cohorts at a time due to different overwintering developmental stages. After overwintering the adult males began to in mid-late April. A positive correlation was observed between the number of adult males caught in traps and the mean density per twig of all motile stages except first stage nymphs of the cryptic mealybugs. The peak time for the first nymph to occur was estimated from the maximum attraction time of the males, and the cumulative degree days (DD) was 350 DD, similar with the preoviposition period.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.169-172
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• 2006

Sex pheromone blends of large black chafer, Holotrichia parallela (Motschulasky), which consist of a major component L-isoleucine methyl ester (LIME) and a minor component (R)-(-)-linalool, showed different attractiveness depending on the mixing ratios of the two components in potato fields in South Korea. The best ratio for H. parallela attraction was 2.5:1 of LIME and (R)-(-)-linalool. The attraction ability of pheromone traps bated with 2.5:1 ratio did not drop up to 14m, but significantly decreased at 21m from H parallela release point. Korean population of H. parallela showed almost same periodical activity to sex pheromone with that reported in Japan, which showing a circabidian periodicity of 48h cycle.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.9-14
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• 1995

From a chemist's perspective, Scarabaeidae is one of the most exciting group of insects to work on the isolation, identification, and synthesis of sex pheromones because-as opposed to Lepidoptera, which by and large utilizes straight chain alcohols, aldehydes, and acetates-the pheromonal chemistry of scarab beetles is remarkably diverse. While species in the subfamily Rutelinae utilize pheromone constituents, which are presumably fatty acid derivatives, the more primitive species in the subfamily Melolonthinae use phenolic, amino acid derivative, and terpenoid compounds. Here, I discuss the recent advances we have accomplished in the identification of scarab sex pheromones with especial emphasis on their chemical diversity. Also, I discuss the potential role of these sex pheromones in insect pest management. Field tests revealed that, in contrast to what has been frequently observed in the Lepidoptera, the higher the dosage of sex pheromone loaded in the traps the greater the capture of scarab beetles. These data suggest that mass trapping is more likely to be useful for scarab pest management than mating distruption.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.165-167
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• 2003

The seasonal occurrence of smaller clearwing moth (Synanthedon tenuis) was monitored with sex pheromone traps in sweet persimmon orchards in Gimhae and Jinju in 1998, 2001, and 2002. Results indicated that it occurred in two generations a year. The first generation of the moth occurred from mid-May to early July, and the second one_from late July to late September, showing the peaks in early June and early to mid-August, respectively.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.289-294
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• 2015

Striped flea beetle, Phyllotreta striolata (SFB) and turnip sawfly, Athalia rosae ruficornis (TSF) are two economically important sporadic pests in radish fields on Jeju island. The response of adult SFB and TSF to a mixture of aggregation pheromone, (+)-(6R,7S)-himachala-9,11-diene and host plant volatile, allyl isothiocyanate (HAI), as well as to yellow and blue sticky traps was examined in radish fields. Adult SFB was more attracted to the sticky trap with HAI, regardless of the color of the sticky trap; however, adult TSF was more attracted on the yellow sticky trap than blue, and no effect of HAI was observed. The adult SFB and TSF can be effectively monitored using yellow sticky traps placed 10 cm above the plant canopy. SFB and TSF had 3 and 5 peak times in a year, respectively. The first peak occurred in the middle of March for SFB and mid-late of April for TSF. We expect that the results of the present study can facilitate minimizing the damage caused by the two important pests in commercial radish fields.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.349-356
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• 2007

Three active components (Z8-12:Ac, E8-12:Ac, and Z8-12:OH) are known in sex pheromone of the oriental fruit moth, Grapholita molesta, and have been commercially available to apply for population monitoring and mating disruption. However, there have been variation among commercial products in pheromone composition and amount impregnated in each pheromone releaser. This study was performed to optimize factors influencing on pheromone monitoring of G. molesta by analyzing pheromone composition/amount, effective period of releaser, and trap type/placement in apple trees. High purity of Z8-12:Ac component was effective to attract males, in which 96% or more of cis acetate isomer component appeared to be optimal composition. Pheromone amounts ($0.01-1\;{\mu}g$) impregnated in each rubber dispenser did not give significant effect on monitoring during 90 days from June to August. "Delta" trap was much more efficient than "cone" trap to collect males. Trap installation was another factor, in which placing traps at canopy level was much efficient than at trunk or ground levels. Pheromone trap monitoring with these optimal factors indicated three to four adult peaks from June to September in addition to high overwintering population from April to May in pesticide-applied orchards in Andong, Korea.