The oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is a major pest of apple, peach, and plum in Korea. As a series of experiment we assessed effect of combined application of an entomopathogenic fungi (Beauveria bassiana ARP-14) and a botanical insecticide (azadirachtin) against male and female of adult G. molesta (<5 days old) in glass scintillation vials. LT50 value of combined application of ARP-14 and azadirachtin (51.9 h) was larger than that of positive control λ-cyhalothrin (34.4 h) in adult female G. molesta. But, adult male G. molesta didn't show any statistical difference between the combined application (34.2 h) and λ-cyhalothrin (44.1). Thus, combined application of ARP-14 and azadirachtin can be an optional management tactic against G. molesta.

Grapholita molesta (Busck) is a major pest of stone fruits. Immature fruits of apricot and plum are well known food source during early summer for G. molesta, but those immature fruits have rarely been evaluated. Thus, we assessed biological and behavioral attributes of G. molesta when provided with immature fruits of apricot and plum in laboratory. The initial response rate (when larva reached to the center from release point in Y-tube olfactometer) of first instar was not different between apricot (70.0%) and plum (60.0%) of which sugar content was more on plum (5.92 brix in apricot and 7.30 brix in plum). However, pupal weight was less in apricot (7.5 mg) than in plum (11.4 mg), and this might be affected by difference in hardness of the fruits (17.2 N on apricot and 13.3 N on plum). The preoviposition period was also longer in apricot (6.3 d) than plum (3.6 d), and fecundity was lower on apricot (64.5) than on plum (135.0). Therefore immature plum fruit would be better food source for G. molesta than apricot during early summer.

Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is an important pest of pome and stone fruits, i.e., apple, peach, and plum. We evaluated single or combined application of an entomopathogenic fungi Beauveria bassiana (Balsamo) Vuillemin. ARP14 (1×108 conidia/mL) and a botanical insecticide of azadirachtin (Azatrol, PBI/Gordon Cooperation) (10 mL/L) against first instar larvae (<5 h old) of G. molesta in glass scintillation vial bioassay. Combined use of B. bassiana ARP-14 and azadirachtin showed higher corrected morality of 100% at 8 h than 71.4% in λ-cyhalothrin used as a positive control.

Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is an important pest of apple, peach, plum, etc. Growers use synthetic chemical insecticides to manage this pest, but G. molesta have developed an insecticide resistance. As botanical insecticides have been rarely studied against G. molesta, we assessed relative toxicity of azadirachtin (azatrol 10 mL/L) in comparison with λ-cyhalothtrin (6.7 mL/20L) in residual assays using both glass scintillation vial coated with the insecticides and apple fruits dipped in the insecticide solutions against first instar larvae (<5 h old) of G. molesta. Azadirachtin showed highest corrected morality of 96.7% at 8h followed by 63.3% in λ-cyhalothtrin in the scintillation vial. On apple dipped in the insecticide solutions, no significance in corrected mortality was found between azadirachtin and λ-cyhalothtrin. Thus azadirachtin can be used as a botanical insecticide for the management of G. molesta.

수확 후 해충방제가 국내 수요 농산물은 물론이고 검역 문제를 해결하기 위한 수출용 농산물에 대해서 요구되고 있다. 특별히 유기 농산물 또는 환경친화형 재배 농산물에 대해서 메틸브로마이드와 같은 화합물을 이용한 기존의 수확 후 처리기술은 의미를 잃게 되었다. 대체 기술로서 CATTS (환경조절열처리기술)라 명명된 물리적 처리기술이 개발되어 사과와 여러 핵과류 과실을 가해하는 곤충과 응애에 적용되고 있다. 본 연구는 국내 사과 수출을 위해 수입국에서 규제하는 복숭아순나방(Grapholita molesta)을 대상으로 CATTS 처리 조건을 결정하는 데 목표를 두었다. 이 해충에 CATTS를 적용하기 위해 사과 과실에 잔류하면서 열에 높은 내성을 보이는 발육시기를 분석하였다. 열처리 조건(44℃, 20분)에서 5령 유충이 가장 높은 내성을 보였다. 환경조건(15% CO2, 1% O2)에서 기기 내부 온도가 25℃에서 46℃까지 증가하는 시기를 CATTS 가열단계로 볼 때, 이 가열 속도가 빠를수록 CATTS 해충 방제 효과가 높았다. 또한 가열단계 후 CATTS 처리 시간이 길수록 CATTS 효율이 증가했다. 특히 가열단계에서 과실 내부온도가 44℃로 이르게 하는 것이 CATTS 효율을 높이는 데 결정적이었다. 이러한 조건들을 종합하여 CATTS표준 처리기술을 결정하였으며, 이 기술은 2,104 마리의 5령을 포함한 4,378 마리 복숭아순나방 유충 피해를 받은 사과에 대해서 100% 방제 효과를 나타냈다.

Insects in temperate climate zones are challenged to endure harsh temperature regimes and the absence of food resources during winter. Many insects overwinter in diapause at different sites. The overwintering sites differ according to the insect species. The study was conducted to investigate the overwintering sites between the two orchard systems for the Grapholita molesta larvae. Overwintering sites of Grapholita molesta were found different between apple grafting systems. More individuals favored the side branches and main bottom trunk as overwintering sites in big tree system (M26) and in dwarf grafting high density system (M9) respectively. There was no significant different between M9 and M26 cultivars in the relative proportion of larvae. However, significant differences were found in the interaction between the overwintering sites and the two M9 and M26 cultivar orchard systems. The natural mortality from the field was estimated as 22.1% and 18.3% from dwarfing, high density orchards and the big tree orchard systems respectively. This study provides valuable information and guidelines to understand the major overwintering sites within different orchard systems for scheduling management actions against spring adult moths population emergence.

Many insects overwinter in diapause in the temperate region. Winter diapause often terminates far yearly than our thought, eg. Many in December. After diapause termination, insect becomes in quiescence. The lower developmental threshold of overwintering Oriental fruit moth larvae is in the range of 7.5-8.4℃ depending on the geographic location. We have determined the developmental period of overwintering OFM larvae from the time series interval collection. Collections were made from mid Jan to late March at 10d interval. Collected larvae were held in a cold chamber at 6°C for 5 days, and then subjected at 20°C with 75% R.H., 16:8(L:D).hr. The developmental period from overwintering cocooned larvae to adults was longest in mid. January collections, became shorter after 31 Jan. collection, then gradually decreased until mid March. Cocooned larvae developmental period became shorter after 31 Jan. while that of pupae became shorter after 20 Feb. During this study, female ratio was not different to 0.5. Mortality of winter collected larvae to adults was 45% including 30% parasitism. Partial explanation of the insect development under the lower developmental threshold was discussed; limitation of linear model estimation, temperature data quality and physiological metabolism after diapause termination. From January to February, daily average temperature fluctuated but under the lower developmental threshold. However, daily maximum temperature became noticeably higher than the lower developmental threshold after 20 Jan. However, this result indicates that after late Jan, physiological state of OFM is altered.

A remote sensing pheromone trap called IT pheromone trap (Korean patent: 10-0982563) was applied to monitor overwintering population changes of the oriental fruit moth, Grapholita molesta, for three successive years in apple orchards. Males of the overwintering populations were attracted during April and May. However, the occurrence peak was delayed and extended to early June in 2010, at which the average spring temperature was significantly lower than the previous years. These overwintering populations could be monitored by the remote-sensing pheromone trap. When the remote-sensing pheromone traps were deployed to apple orchards of different provinces in Korea in 2010, the maximal overwintering populations of G. molesta were monitored at May in all areas. However, the population sizes monitored were significantly different among different localities. This study suggests a practical application of IT pheromone trap to monitor G. molesta in field conditions.

Mating disruption (MD) using synthetic sex pheromone lures has been used to control the Oriental fruit moth, Grapholita molesta (Busck), in apple orchards. In Korea, where several small apple orchards are clustered but independently managed, its efficacy has been suspected mainly due to immigration of any mated females from nearby untreated cultivating areas. This study developed an edge treatment technique to decrease any local MD-free zones in a specific MD-treated farm and to trap any immigrating mated females by installing MD lures and food traps around the apple farm with 10 meter intervals. The addition of the edge treatment to the MD significantly prevented leaf and fruit damages induced by G. molesta compared to MD only. Moreover, this study tried to optimize the MD control technique by determining frequency of MD application. It suggests two MD applications with the edge treatment at the end of March and at the early of July to be effective throughout the entire apple growing seasons.

Local and seasonal populations of the oriental fruit moth, Grapholita molesta , were monitored with sex pheromone trapping and RAPD (random amplified polymorphic DNA) molecular marker to analyze their movement in apple orchards. To detect their movements among farms, pheromone traps were placed at regions between apple farms (‘outside-farms’) as well as within-farms (‘inside-farms’). Four seasonal adult peaks were evident in apple-cultivating fields from April to October in both trappings of inside- or outside-farms. After overwintering generation, populations of inside-farms were significantly reduced with frequent insecticide applications, compared to populations of outside-farms. Within apple farms, G. molesta tended to be unevenly distributed because of significant sublocal preference. Active movements of local and seasonal populations of G. molesta were supported by gene flow analysis using RAPD marker. Monitoring data using sex pheromone and seasonal reduction in initial genetic differentiation detected in the overwintering populations suggest that there must be significant movement of G. molesta among different orchards in apple-cultivating areas.

Mitochondrial genome is inherited in maternal origin without recombination by mating and its specific regions have been used to monitor insect pest populations in agriculture. The oriental fruit moth, Grapholita molesta, is a serious pest on apple industry by its direct damage on fruits. This study reports a full sequence of mitochondrial genome of G. molesta. Sequence contigs were made by primary PCRs on conserved regions and subsequent PCRs to fill the gaps. Annotated genes were highly matched to the sequences of other lepidopteran species. However, a few positions of tRNA genes on the genome were different to other mitochondrial genomes.

Local and seasonal populations of the oriental fruit moth, Grapholita molesta, were monitored with sex pheromone trapping and RAPD (random amplified polymorphic DNA) molecular marker to analyze their movement in apple orchards. To detect their movements among farms, pheromone traps were placed at regions between apple farms ('outside-farms') as well as within-farms ('inside-farms'). Four seasonal adult peaks were evident in apple-cultivating fields from April to October in both trappings of inside- or outside-farms. After overwintering generation, populations of inside-farms were significantly reduced with frequent insecticide applications, compared to populations of outside-farms. Within apple farms, G. molesta tended to be unevenly distributed because of significant sublocal preference. Active movements of local and seasonal populations of G. molesta were supported by gene flow analysis using RAPD marker. Monitoring data using sex pheromone and seasonal reduction in initial genetic differentiation detected in the overwintering populations suggest that there must be significant movement of G. molesta among different orchards in apple-cultivating areas.

An unidentified moth was captured in sex pheromone traps of the oriental fruit moth, Grapholita molesta, especially at spring season in apple orchards and their vicinity. Though the captured males were similar in appearance to G. molesta males, they were easily distinguished by a marked difference in body size. Their occurrence pattern was also similar to that of overwintering G. molesta population from April to May, at which more males were captured in the pheromone traps installed in the vicinity of apple orchards than within apple orchards. After May, they were no longer captured in the pheromone traps. To investigate any larval damage due to this unidentified moth, molecular markers needed to be developed. Four PCR-RFLP markers originated from cytochrome b region of mitochondrial DNA could distinguish this unidentified moth from G. molesta.

A wax-typed pheromone dispenser has been developed and applied to control outbreak of the oriental fruit moth, Grapholita molesta, in apple orchard. To optimize its application technique, this study analyzed effect of different amounts of the pheromone dispenser on mating disruption (‘MD’) of G. molesta. Different pheromone dispenser amounts significantly influenced the MD effect assessed by cumulative male adult catches monitored respectively by sticky delta trap and food trap, and resulted in differential damage on host plants. In a field test during entire growing season, a standard amount (120 g per 0.117 ㏊) of wax-typed pheromone dispenser was proved to be effective to suppress outbreak of G. molesta adults and to prevent host plant damage as much as a current commercial MD product (Isomate<SUP>Ⓡ</SUP>). This study also demonstrated an effectiveness of deployment of food trap barriers around MD-treated area to prevent immigration of mated females from outside untreated areas. These results indicate that the wax-typed pheromone dispenser can be applied to control field G. molesta populations and its co-application with food trap barriers would be optimal to maximize MD efficacy.

Spring phenology of the oriental fruit moth, Grapholita molesta, was monitored using sex pheromone traps in apple cultivating areas. Their occurrence was earlier in southern areas and their population sizes were significantly different among orchards even in a local cultivating zone. The overwintering populations appeared to move between local orchards, based on the fact that monitoring data obtained at the sites between orchards were similar to those of nearby orchards. However, within orchards, these adult movements appeared to decrease and showed skewed occurrences at the side of upwind direction or close to neighboring orchards. At initial occurrence peak (April 20-25), the overwintering populations of the different localities were collected and analyzed in their genetic distances. PCR-RAPD analysis indicated that there were significant genetic differences among the overwintering populations of G. molesta. This genetic differentiation of overwinterin populations may be due to genetic bottleneck following differential selection pressures against the subpopulations of G. molesta during winter on the basis of the RAPD analysis that each early spring population was significantly different to its previous fall population in the same locality.

This study demonstrates a variability in efficacy of mating disruption against the oriental fruit moth, Grapholita molesta, populations infesting apples cultivated in differential environmental conditions. Throughout the growing seasons, trap catches of G. molesta male moths and damaged leaf and fruit were examined to evaluate the efficacy of a commercialized mating disruptor. Treatment of the mating disruptor significantly reduced the trap catches of male moth in treated plot, compared to those of the untreated plot. This reduced trap catches were significantly correlated with leaf and fruit damage. Moreover, the highest host damage occurred in June just after the highest overwintering adult peaks in both plots. The treatment of mating disruptors in Chungsong effectively disrupted the overwintering population in April and May, resulting in no noticeable host damage during the following growing seasons. However, there was a marked difference in host damage between two plots, especially in late seasons. Variation in the efficacy of mating disruption technology in terms of host damage appeared to be related with nearby pheromone-untreated orchards, which may result in the immigration of gravid females.

Oriental fruit moth, Grapholita molesta, is a serious pest on apples. To control this pest in an environmentally friendly method, mating disruption strategy using sex pheromone has been developed. Area-wide application of mating disruption has been needed to be effective, with little understanding on how much size of apple cultivating area should be treated in one time application of the mating disruption technique. On this matter, we needed to determine a minimal mating active zone of G. molesta that should be applied with mating disrupters to be effective. Molecular markers to discriminate a specific population should be developed to trace population migration for reproductive behaviors. Here we developed two effective molecular markers using random amplified polymorphic DNA (RAPD) technique. Different field populations of G. molesta, based on locations and seasons, were analyzed with these markers. In a specific location, G. molesta populations varied in genetic composition with different seasons. Different local populations showed differential variation according to their relative distances among apple orchards. In overall, genetic variation among different populations became lessen with progression of seasons.