• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.281-289
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• 2004

The sex pheromone blend (28-12AC : E8-12AC : Z8-12OH = 95 : 5 : 1) of oriental fruit moth, Grapholita molesta (Busck), was evaluated with reference to its male attractivity at different dosage and lure longevity of 1.0 mg in a field condition. Also, degree-days (DD) were calculated up to major phenological events of G. molesta using seasonal adult flights monitored by pheromone traps and egg population densities in early season in Suwon peach orchards. In the range of 0.1-4.0 mg dosage examined, G. molesta males caught in pheromone trap decreased with increasing total pheromone doses. The highest number of G. molesta males were attracted in traps baited with 0.1 mg-lure, and there were no significantly differences among 0.5 to 4.0 mg-lure. In longevity test with a 1.0 mg-lure, there was no difference in mean numbers of G. molesta males caught between traps with fresh-baited lures every 20d and field-lasted lures up to ${\approx}50d$ after trap installation, but thereafter more G. molesta males were attracted in the field-lasted lures than in the fresh-baited lures. Accumulated degree-days (DD) from January 1 to the first adult emergence (biofix) were 39DD at a lower threshold temperature $8.1^{\circ}C$. Degree-days from the biofix up to the 1st adult peak through 4th peak were 98DD, 620DD, 1233DD, and 1916DD, respectively. Required degree-days from the 1st adult peak to the 1st egg peak were 130DD, while the 2nd egg peak timing was simultaneous with the 2nd adult peak. Further, management strategies of G. molesta were discussed in peach orchards.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.393-398
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• 2020

The blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on cultivated blueberries in Korea. To develop a sensitive tool for monitoring this pest in blueberry orchards, we compared the attractiveness of host plant volatiles and sex pheromone to D. oxycoccana adults. We performed gas chromatography-mass spectrometry (GC-MS) analysis of solid-phase microextraction (SPME)-collected volatiles that were released from blueberry ('Darrow' cultivar). The analysis revealed two major volatiles, cinnamaldehyde and cinnamyl alcohol from flowers; and three major volatiles, β-caryophyllene, germacrene D, and α-farnesene from shoots and young fruits. In field tests conducted in Gunsan, Korea in 2019, commercialized cinnamaldehyde, cinnamyl alcohol, β-caryophyllene, and α-farnesene, used singly or in quaternary combination, were unattractive to the blueberry gall midge. However, traps baited with the known sex pheromone (2R,14R)-2,14-diacetoxyheptadecane attracted significantly more males than the treatments with plant volatiles or the control. No synergistic effect was observed between sex pheromone and plant volatiles. Male D. oxycoccana were captured in the pheromone traps from May to August, with three peaks in mid-May, late June, and late July in Gunsan blueberry fields in 2020.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.107-112
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• 2002

Seasonal occurrence pattern of the peach pyramid moth (PPM), Dichocrosis punctfferahs, was studied by sex pheromone traps and mercury light traps in several Fuyu persimmon orchards under different control pressures in southern region of Korea in 2000 and 2001. Fruit damage by the larvae was also checked at harvesting time from 1999 to 2001. The pattern showed 3 distinct peaks; the 1st one in mid to late June, the 2nd one in mid to late August, and the 3rd one in late September. Number of PPM catches was higher in less controlled than in intensively controlled orchards. There were no persimmon fruits damaged by the larvae of PPM and persimmon fruit moth, Stathmopoda masinissa, in our samples from the testing orchards at harvesting time. Therefore, it is unlikely that these two quarantine pests are included in the exporting fruits. Considering flora adjacent to the tested orchards and zero levels of fruit damage by the larvae, there is a strong possibility that the moths flew from neighbouring chestnut trees or other host plants to be attracted to the traps in the persimmon orchards.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.31-36
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• 2005

Adoxophyes spp. are the major rests of a pear. The larvae attack both leaves and fruits. (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac) and 10-methyldodecyl acetate (10me-12:Ac) have been reported as the sex pheromone components of the genus Adoxophyes. Our objective was to determine the difference in sex pheromone composition of three different A. spp. populations each from Cheonan, Sangju, and Naju area orchards in Korea. Gas chromatography (GC) analyses of pheromone gland extracts of virgin females confirmed the presence of two compounds (Z9-14:Ac and Z11-14:Ac) in Cheonan and Sangju populations, and four compounds (Z9-14:Ac, Z11-14:Ac, E11-14:Ac and tome-12:Ac) in Naju population. The Z9-14:Ac and Z11-14:Ac were detected in the ratio of 80:20 in the Cheonan population and 3:97 in the Sangju population. Females of Naju population produced sex pheromone blend consisting of Z9-14:Ac, Z11-14:Ac, E11-14:Ac and 10me-12:Ac at a ratio of 31:62:6:1. Field trapping tests in pear orchards with Z9-14:Ac and Z11-14:Ac indicated that maximum captures of the male were obtained with traps baited by 80:20 in Cheonan, 10:90 in Sangju, and 30:70 in Naju. These results suggest that there are remarkable geographical variations in the sex pheromone composition of A. spp. in pear orchards in Korea, and taxonomic classification of these species must be carefully assessed.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.161-167
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• 2006

The citrus leafminer (CLM), Phyllocnistis citrella Stainton, is an oligophagous pest of Rutaceae family, especially Citrus spp. occurring in most worldwide citrus-growing areas. This study was conducted to evaluate a sex pheromone chemical of CLM, (Z,Z)-7,11-hexadecadienal (7Z,11Z-16:Al) in monitoring CLM by trap types, the diel activity and the influence of some weather factors on trap catch. CLM was well attracted on a trap baited 7Z,11Z-16:Al 1mg. Sticky wing trap was more effective than bucket trap. Most caught CLM were attracted at 2$\sim$6 a.m. regardless of season, and activity time of CLM was affected by sunrise time as well as sunset time. The trap catch of CLM was more influenced by wind velocity than temperature for activity time of CLM. The number of caught CLM was fallen at below 13$^{\circ}C$, but there was little effect for trap catch at over that temperature. The average wind velocity at over 2.0 m/sec made the number of caught CLM drop down. The precipitation did not affect the number of caught CLM when the average wind velocity was lower than at 2.0 m/sec.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.105-115
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• 2018

The comstock mealybug is one of the serious insect pest in pear. It is necessary effective control methods such as attractive sex pheromone. Using sex pheromones is necessary for studying the physiology and ecology of insect pests. In the present study, the sex pheromone of comstock mealybug was used for investigating the flying acts of the adult male. As temperature increased, the development period of eggs shortened, but it was longer at $30^{\circ}C$. The mean number of eggs laid was 482 at $25^{\circ}C$ and males constituted 37% of the experimental population at $30^{\circ}C$. The flight of the male comstock mealybug was mostly restricted to a 2-4 hour period after sunrise, even if condition of light period is changed. Male mealybugs were incapable of upwind flight towards an attractant when air velocity was 1.5 mph. Preference of height was tested in a pear orchard. The ineffective heights of the traps were 2 and 2.5 m, whereas the effective heights were 1 and 1.5 m. Many captured males at 0.5, 1, and 5 m, and the number of captured males were similar in 10, 15, and 20 m. Male mealybugs were captured up to a distance of 50 m, suggesting that it is possible to control the male mealybugs that are more than 50 m away when sex pheromone traps are used.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.299-303
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• 1999

Studies were conducted in Mt. Namsan, Seoul, during the summer of 1997 and 1998 using racemic disparlure to determine seasonal occurrence and circadian activity in male gypsy moth, and size of egg mass and wing length of male moth. Male gypsy moths occurred from middle part of July until middle part of August and peaked in late part of July. Circadian activity of male moths initiated from 12: 00h and continued until 21: 00h, and the peak time was between 14: 00h and 17: 00h. Mean number of moths captured per trap in 1997 was larger than that in 1998, however, eggs per mass, egg size and wing length were not significantly different between the two years, 1997 and 1998.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.449-459
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• 2012

Fruit borers such as Grapholita molesta, G. dimorpha and Carposina sasakii are major pests of plum in Korea. Population densities and seasonal occurrence were monitored using the synthetic sex pheromone trap in Uiseong and Gyeongsan, two important major plum growing area in Korea. In 2010 and 2011, adults of G. molesta were caught from mid April with the peak of late April, and then undergone three more generations in Gyeongsan. Grapholita dimorpha appeared from late April and they showed three peaks until late September. Both Grapholita species occurred a few days later in Uiseong than in Gyeongsan where the latitude is $1^{\circ}$ lower. There was no difference of the phenological occurrence of C. sasakii between Gyeongsan and Uiseong, showing the same patterns of two or three peaks. Population size was in order of G. molesta, G. dimorpha and C. sasakii with 63:16:20 and 47:35:18 in Gyeongsan and 51:18:31 and 46:13:36 in Uiseong, in 2010 and 2011 respectively. There was no difference between the numbers of Grapholita species caught in the trap installed inside and outside of the orchards.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.77-83
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• 2022

This study was conducted to determine the optimal composition of sex attractant for monitoring adults of the tobacco cutworm, Spodoptera litura, in Korea. Lures of different compositions from the two sex pheromone components the female, (Z,E)-9,11-tetradecadienyl acetate (Z9E11-14:Ac) and (Z,E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac), were compared for male attraction using synthetic chemicals, rubber septa, and funnel traps in soybean and peanut fields. After sequential tests were conducted using three sets of the two components different ranges from 5:5 to 10:1, from 9:1 to 99:1, and from 9:1 to 39:1, the 19:1 ratio was identified as the most efficient composition. However, S. litura males were barely caught in the trap of the Z9E11-14Ac single component lure. The results show that both the sex attractant compounds are necessary for monitoring adults S. litura males. The higher the pheromone amount in the dispenser in the range from 0.1 to 10 mg, the more males were attracted. Furthermore, the trap height of 1.5 m was optimal for male capture.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.46-51
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• 2007

In this study, two commercial mating disruptors were compared in terms of disruption of Oriental fruit moth, Grapholita molesta, male orientation, in which a new dispenser type, $SPLAT^{(R)}$, was compared with a current dispenser type, $Isomate^{(R)}$-M ROSSO. For this assessment, the last three year field monitoring data were analyzed for the efficacy of Isomate type dispenser. Then two commercial dispensers were compared in different localities with sub-locality replications during identical monitoring period from mid February to late August. There appeared to be four adult population peaks, in which the overwintering population size was positively correlated with the following reproductive population sizes. Isomate type dispenser effectively suppressed G. molesta populations during all growing seasons with some annual variation in its efficacy. Between two dispensers, SPLAT type was much effective. The difference in their efficacy may be caused by the difference in composition of major pheromone component.