Soon-Won Lee

Recent Occurrence Status of Two Major Fruit Moths, Oriental Fruit Moth and Peach Fruit Moth in Apple Orchards

This survey was conducted from 1992 to 2005 in the major apple producing districts in southern part of South Korea including 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 , 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.

DNA Markers Applicable for Identification of Two Internal Apple Feeders, Grapholita molesta and Carposina sasakii

Two fruit moths of the oriental fruit moth, Grapholita molesta (Busck), and the peach fruit moth, Carposina sasakii (Matsumura), infest apples in Korea by internally feeding behavior. C. sasakii is a quarantine insect pest from some other countries importing Korean apples. G. molesta is not a quarantine insect pest, but can be incorrectly identified as C. sasakii especially when it is found inside apple fruits at its larval stages because it is not easy to identify the two species by morphological characters alone. This incomplete identification results in massive economical loss by fruits needlessly destroyed or turned away at border inspection stations of the importing nations. This difficulty can be overcome by molecular DNA markers. Several polymorphic regions of mitochondrial DNA of both species were sequenced and used for developing specific striction sites and polymerase chain reaction (PCR) primers. Based on these sequences, three diagnostic PCR-restriction fragment length polymorphism (RFLP) sites were detected and validated for their practical uses. Also, species-specific PCR primers were devised to develop diagnostic PCR method for identifying the internal feeders.

Development of Wax-typed Pheromone Dispenser for Mating Discruption of the Oriental Fruit Moth, Grapholita molesta, and Its Application Technique

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 ha) 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(). 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 fuod trap barriers would be optimal to maximize MD efficacy.

Efficacy Test of Mating Disruptors Using Food Trap of Oriental Fruit Moth, Grapholita molesta (Busck)

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.

Management of Grapholita molesta and Carposina sasakii Using Mating Disruption in Non-Chemical or Organic Apple Orchards

ABSTRACT: The efficacy of mating disruptors MD-IKR (Isomate-KR) and MD-CR (Confuser-R) for controlling Grapholita molesta (Busck) and Carposina sasakii (Matsumura) was evaluated in non-chemical or organic apple orchards. For G. molesta, the efficacy of MD-IKR and MD-CR in Chilgok was 99.8 and 99.8% (2011) and 92.4 and 96.7% (2012), respectively, showing different mating reduction values. The efficacy of MD-IKR and MD-CR in Cheongsong was 99.1 and 92.8% (2011) and 99.6 and 99.6% (2012), respectively. For C. sasakii , the efficacy of MD-IKR and MD-CR was 100% at Chilgok and Cheongsong in 2011 and 2012. Evaluatio nof the shooting and fruit damage rates showed that the efficacy of the mating disruptors in controlling G. molesta and C. sasakii was betterthan that of the non-control. However, there was no significant control difference between using the mating disruptors and the conventional control. No difference in the efficacy of the two mating disruptors was observed. We believe that MD-IKR could be an alternative to MD-CR.Key words: Apple, Mating disrupter, Grapholita molesta, Carposina sasakii, Management초 록: 복숭아순나방과 복숭아심식나방의 방제를 위해 교미교란제 MD-IKR (Isomate-KR)과 MD-CR (Confuser-R)의 효과를 무농약·유기재배 사과원에서 평가하였고 관행방제 사과원과 비교하였다. 2011년 칠곡지역의 복숭아순나방에 대한 두 종의 교미교란제에 대한 교미저해율은 99.8%였고, 상대적으로 청송지역의 교미저해율이 각각 99.8과 92.8%로 칠곡지역과 차이가 있었다. 2012년 칠곡지역의 교미저해율은 각각 92.4와 96.7%였다. 청송지역에서 교미저해율은 99.6%로 가장 높은 교미저해율을 보였다. 2011년 2012년의 복숭아심식나방에 대한 교미저해율은 두 교미교란제 모두 100%로 높게 나타났다. 두 교미교란제는 복숭아순나방과 복숭아심식나방이 방제효과에 대하여 무방제구 대비 방제효과가 월등하였고, 관행방제와 비교했을 때 통계적으로 유의성 없이 방제효과가 대등하였다 . 두 종의 교미교란제와 관행재배구의 새순과 과실피해율은 무방제구 대비 유의성있는 방제효과를 보였다. 두 종의 교미교란제 간에는 효력의 차이가 없어 MD-IKR 이 MD-CR을 충분히 대체할 수있을 것으로 판단된다.검색어: 사과, 교미교란제, 복숭아순나방, 복숭아심식나방, 관리*Corresponding author: choikh@korea.krReceived August 16 2013; Revised November 25 2013Accepted February 5 2014우리나라의 무농약･ 유기재배 사과원에서 문제가 되는 주요 해충들은 복숭아순나방, 복숭아심식나방, 사과혹진딧물, 사과면충, 사과유리나방 등이 있는데 , 이 중 과실을 가해하는 심식나방류 해충인 복숭아순나방과 복숭아심식나방에 의한 피해가 크다(Choi et al., 2010). 복숭아순나방(Grapholita molesta (Busck)(Lepidoptera: Tortricidae))은 중국 서북지역에서 유래되어 현재는 북미 , 남미, 유럽 및 호주 등 전 세계적으로 분포하고 (Rothschild and

Species Dominance of Tetranychus urticae and Panonychus ulmi (Acari: Tetranychidae) in Apple Orchards in the Southern part of Korea

이 연구는 사과원에서 20년동안 두 종 응애의 밀도변화를 조사하기 위하여 수행하였다. 사과나무를 가해하는 두 종의 응애 해충, 점박이응애(Tetranychus urticae)와 사과응애(Panonychus ulmi)의 발생을 1992년부터 2011년까지 8개 도시 포함, 한국의 남부지역에 위치한 사과주산지역에서 조사하였다. 20년간의 추세는 많은 과원이 1992년부터 1999년까지는 점박이응애가 주로 가해를 하였지만 2000년도부터는 사과응애가 우점하기 시작했다. 사과응애의 평균관찰밀도는 일정했고 점박이응애의 밀도는 이 기간동안 일정하지 않았다. 5년주기별 발생추세 분석은 점박이응애의 밀도가 2002년 이후에 감소하는 것을 보여주었다. 4월부터 9월까지 월별피해과원율과 두종 응애의 평균발생밀도는 사과응애의 밀도가 4월에 높지만 점박이응애의 밀도가 5월부터 9월까지 높았다. 이런 변화는 살충제 살포횟수, 초경재배관리, 질소비료 사용의 감소와 전체적인 과원관리의 변화 등으로 기인한다. 그러나 이러한 예측은 이를 증명하기 위해 보다 자세한 연구가 필요하다. 본 연구를 통해 비료살표와 같은 재배법과 살충제 살포횟수와 종합적해충관리 등의 환경적 변화가 사과원에서 두종 응애의 우점종과 발생밀도에 영향을 준 것으로 보인다. 【This study investigated population fluctuations in two mite species in apple orchards over 20-year period. The occurrence of two major mite pests infesting apple trees, two-spotted spider mite Tetranychus urticae and European red mite Panonychus ulmi (Acari: Tetranychidae), was investigated from 1992 to 2011 in major apple-producing districts, including four to eight cities, in the southern part of the Republic of Korea. The 20-year trend revealed that more orchards were infested by T. urticae from 1992 to 1999, but thereafter P. ulmi became dominant. The observed mean density of P. ulmi was consistent, whereas that of T. urticae fluctuated during this period. The analysis of occurrence in four time periods reveals that the density of T. urticae decreased after 2002. The monthly sampling, revealed that the density of P. ulmi was higher in April, whereas the density of T. urticae was higher from May to August. This change may be due to a change in the frequency of pesticide spraying, ground vegetation management, a decrease in nitrogen fertilization, and the overall orchard management practices. However, this projection should be examined in more detail. On the basis of the findings of this study, it can be concluded that cultural practices, including fertilization, and environmental changes, such as pesticide spray frequency and integrated pest management practices, affect species dominance and population densities of the two mite species in apple orchards.】