This survey was conducted from 1992 to 2005 in the major apple producing districts in southern part of South Korea including 4~8 cities, to know the occurrence and damage level of two major pests, Carposina sasakii and Grapholita molesta that attack apple fruit. The fruit damage by G. molesta during the harvest period ranged from 0.02 to 1.64%. A tendency of higher damage of G. molesta was observed after 1997 compared with the previous years. The other hand, the fruit damage by C. sasakii was 0.02 to 1.30%, and the damage level was very low with fruit damage of ＜ 0.3% except 1998. The orchard infested with G. molesta was 13 to 71%, while 12 to 57% with C. sasakii. The rates of orchards where fruit damage by G. molesta was found were higher than those by C. sasakii after 1997. The tendency of fruit damage rates in the orchard where the most fruit damage was found was same with the trend of orchard rates infested with the pests. The maximum damage rate by G. molesta was 20.0% in 2005, while 4.5% by C. sasakii in 1998. The damaged shoot rates by the first generation G. molesta was 0.1~8.1%, and it had a positive correlation with the rates of fruit damage during the harvest period. Consequently, it is concluded that G. molesta is dominant species compared with C. sasakii in commercial apple orchards recently.

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 ㎍) 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.

This study was performed to estimate the efficacy of three commercial mating disruptors for the control of oriental fruit moth, Grapholita molesta (Busck), using a food-baited trap to collect field females. Mated female ratios estimated in the mating disruptor-treated areas were compared with the estimates of male trap captures, and both estimates were evaluated on the basis of crop damage measured by shoot tip damage caused by G. molesta. Both males and females were attracted to the food trap-baited with terpinyl acetate in apple orchard. Spermatophore of G. molesta was similar to female bursa copulatrix in size. Though there was more than 95% reduction in male trap captures indicating significant mating disruption, significant crop damage occurred on apple leaf buds, in which more than 35% of captured females were mated. This study demonstrates that assessment of the mated females would be more reasonable to represent the efficacy of mating disruptor(s) than the assessment of the male captures in G. molesta.

Three sex pheromone components (cis-8-dodecenyl acetate (Z12Ac), trans-8-dodecenyl acetate (E12Ac), cis-8-dodecenol (Z12OH)) of the Oriental fruit moth, Grapholita molesta, were chemically synthesized. Especially to increase the composition of cis-stereoisomer, a triple bond intermediate was hydrogenated at -20℃ with catalytic Pd/BaSO₄. The resulting product consisted of the acetates with a stereoisomer ratio in 92:8 (Z:E). The biological activity of the synthesized pheromone compounds was analyzed both in male responses and orientation disruption. The indoor pheromone effect was determined by male flight behavior showing wing movement in response to lure. Different mixtures of the synthetic pheromone components were prepared by mixing acetate and alcohol components in 100:0, 99:1, and 90:10 (g/g) and tested with a comparison of a standard commercial pheromone lure. The highest pheromone effect was observed in only acetate mixture (100:0) and the effect was reduced with the addition of the alcohol component. This indoor pheromone effect could be observed in field monitoring trial, in which 100:0 mixture showed the highest trap catches. Orientation disruption assay was conducted indoor by using a cage, in which the center had a commercial lure on sticky plate and the four candidates were placed at 6 ㎝ away from the central lure on each of four directions. Test males were released to the arena during overnight (12 h) and then the caught males on the sticky plate were counted. The synthesized pheromone as well as the commercial pheromone showed 100% orientation disruption. However, the orientation disruption effect was reduced with decrease in the number of the surrounding disrupting pheromone baits. These results clearly suggest that the synthesized sex pheromone of G. molesta is biologically active and can be used for field mating disruption.

Efficacies of two commercial mating distruptors (SPLAT<SUP>®</SUP> and Isomate<SUP>®</SUP>-ROSSO) were evaluated on field overwintering populations of Oriental fruit moth, Grapholita molesta (Busck), in four apple orchards. Based on the monitoring with sex pheromone traps, all the orchards (Youngchun, Kyungsan, Chungsong, and Youngju in Korea) exhibited significant overwintering populations from late April to late May. Both mating disruptors that were applied 10 days before the monitoring period significantly inhibited the male orientation to the monitoring lures, in which SPLAT type was more effective than Isomate type in the disrupting efficacy. The disruption of male orientation was highly correlated with the reduction in the early leaf damage caused mostly by G. molesta.

배 과수원에서 복숭아순나방의 발생과 피해에 대하여 1996년부터 2000년에 걸쳐 나주 지역에서 조사하였다. 배나무에서 월동하는 유충의 밀도는 조생종에서 낮았으나 감천배와 만삼길과 같은 만생종에서 높은 경향을 나타내어 품종의 수확시기에 따라 뚜렷한 차이를 보였다. 그리고 대부분의 월동 유충은 배나무의 주지와 주간과 같이 지표면과 가까운 곳에서 월동하였다. 월동유충은 2월 중순부터 용화하기 시작하였고 3월 하순부터 우화하였다. 배 과수원에서 복숭아순나방은 3월 하순부터 10월 상순까지 페로몬 트랩에 유인되었으며 년 4회 발생하는 것으로 조사되었다. 모든 발생 세대의 유충은 배나무의 신초와 과실을 가해하였다. 그러나 1, 2세대의 유충은 주로 신초에 피해를 주며 3, 4세대 유충은 과실을 가해하는 것으로 조사되었다. 심식나방류 유충에 의해 피해를 받은 배 과실 중에서 거의 대부분은 복숭아순나방에 의한 것이었으며 복숭아심식나방과 배명나방 유충에 의한 피해 과실은 발견되지 않았다.