본 연구는 북방수염하늘소 성충이 집합-성 페로몬 트랩에 유인되는 시기를 명확하게 규명하기 위해 수행하였다. 또한 집합-성 페로몬에 유 인된 개체의 난황 성숙도를 조사하여 집합-성 페로몬 트랩에 유인되지 않은 개체와 비교하였다. 이를 위해 홍릉시험림 내 망실 안에 유인제인 집합-성 페로몬을 매단 다중깔때기트랩과 집합-성 페로몬을 매달지 않은 다중깔때기 트랩을 각각 1개씩 배치하고, 우화망실에서 채집한 북방수염하 늘소 성충을 우화시기별(우화 직후, 후식 1일차, 후식 7일차, 후식 10일 경과 후 교미)로 그룹화한 후 트랩이 배치된 망실 안에 방사하여 트랩에 포획 여부를 조사하였다. 각각의 시기별로 80개체(20개체씩 4반복)를 대상으로 실험하여 총 320개체를 망실 내에 방사하였다. 조사 결과, 우화 후 7일 동안 섭식한 개체들의 유인 포획률이 가장 높았으며, 교미 후에는 유인 포획률이 급격히 낮아지는 경향이었다. 또한 집합-성 페로몬이 있는 경 우에만 후식 7일차 그룹의 유인 포획률만 통계적으로 유의미한 차이를 보였다. 성별에 따른 유인 포획률의 경우, 암컷이 수컷에 비해 많이 포획되긴 하였으나, 암컷과 수컷 간의 유인 포획률 차이는 없는 것으로 확인되었다. 우화 직후와 후식 1일차에는 모든 개체에서 난황이 미성숙한 상태였으나, 후식 7일차와 교미 후에는 모든 개체에서 성숙한 난황을 확인할 수 있었다. 따라서 페로몬트랩은 우화 후 초기에 후식을 통한 소나무재선충 전파가 가능하므로 소나무재선충병의 확산 억제를 막기에는 제한적일 가능성이 있다. 반면, 성적으로 성숙한 성충을 포획하고, 야외 발생을 조사 하는 등으로는 활용 가능성이 있을 것이다.

Monochamus saltuarius Gebler are the insect vector of the pine wood nematode (PWN), Bursaphelenchus xylophilus (Steiner & Buhrer) mostly in the mid-northern areas of South Korea. In 2017, we installed sentinel logs to lure efficient parasitic wasps of the vector and to evaluate ecological characteristics of parasitoids in prior to the development of biological control strategy for the PWN transmitting insect vector. As a result of the survey, we found Spathius verustus Chao (Hymenoptera: Braconidae) as a predominant parasitoid with the highest parasitism rate among six species of larval parasitoids. The parasitism rate was higher along the edge (0m of the forest depth) of the survey sites than the inner sides (20m and 40m of the forest depth). Also, the parasitoid showed highest parasitism rate in late-May at one of Gapyeong_sites, where was supposed to be the oldest infected areas. Lastly, the parasitism rate along the trap heights was higher at height of 0m than the 1.8m above the ground.

소나무재선충병의 매개충인 북방수염하늘소의 예찰 및 방제방법 효율 개선을 위하여 트랩유형별 매개충의 유인포획 및 산란효과를 비교 검증하였다. 춘천시 지내리의 잣나무 조림지와 인근 활엽수림을 대상지로 하여 각 사이트내에 집합페로몬 트랩 단독 처리, 산란유인목 단독 처리, 복합처리구를 설치하고 북방수염하늘소가 중부지역에서 주로 활동하는 4월 25일부터 8월 31일까지 1주일 간격으로 확인하였다. 연구결과 대상지별로는 잣나무 조림지가 단순 활엽수림보다 매개충 유인효과가 높은 것으로 나타났다. 트랩유형별로는 단순 멀티펀넬 트랩에 유인되는 매개충의 비율은 집합페로몬 단독 처리시 복합처리구 보다 매개충의 유인효과가 높은 것으로 나타났다. 산란유인목은 10~11월경 확인, 유인율과 산란율을 종합 비교하여 방제방법 효율 개선을 위한 기초자료로 활용할 예정이다.

소나무재선충병의 매개충인 북방수염하늘소의 체내 선충보유량에 따른 비행능력의 차이를 구명하기 위하여 춘천시 지내리의 잣나무림에서 어리소나무재선충(Bursaphelenchus mucronatus)에 감염이 확인된 북방수염하늘소 암·수 각 20마리를 채집, 실내사육 후 우화-섭식 1 주일이 지난 시점부터 1주 간격으로 Flight mill을 이용하여 비행실험을 진행하였다. 동시에 사육통 바닥에 여과지와 섭식한 잣나무 신초를 3~4일 마다 교체 후 Baermman funnel법으로 소나무 재선충을 분리하여 그 수를 조사, 비행능력과 선충보유량의 관계를 조사하였다. 그 결과 약 50,000마리 이상 선충을 체내에 보유시 비행능력이 급감하는 것을 확인 할 수 있었으나, 전체적으로 선충의 체내 보유량에 따른 비행능력의 차이는 상관관계가 없는 것으로 확인 되었다.

Pine wilt disease caused by Bursaphelechus xylophilus has continued to expanding in Korea since its first occurrence identified from Busan in 1988. The direction of spread and density of two vector insects, Monochamus saltuarius and M. alternatus, are closely associated with the expansion and occurrence of pine wilt disease being observed in Korea. In 2016, a pheromone trap was installed to investigate the density of each vector. A correlation between the density of two insect vectors and the number of trees infected by pine wilt disease was further investigated in Gyeongnam, Gyeongbuk, Ulsan, and Jeju. To perform a correlation analysis, the number of infected trees was counted within a radius of 50m from which the pheromone traps were installed. In addition, factors that might have an effect on the density of vectors were investigated. This includes the altitude, temperature and forest type from the site where the pheromone traps were installed.

The Sakhalin pine longicorn, Monochamus saltuarius Gebler (Coleoptera: Cerambycidae), is an insect vector of the pine wilt nematode (PWN), Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, and is widely distributed in central Korea. M. saltuarius is a forest pest that seriously damages Pinus densiflora and Pinus koraiensis forests. We examined the effect of electron beam irradiation on the mating, DNA damage and ovarian development of M. saltuarius adults and sought to identify the optimal dose for sterilizing insects. Our results suggest that pine wilt disease can be effectively controlled if a large number of sterilized M. saltuarius adults are released into the field.

소나무재선충과 근연종인 Bursaphelenchus 속 2종간의 매개충 채내 침입력과 경쟁력을 비교 실험하였다. 공시충은 Bursaphelenchus xylophilus (이하 Bx), B. mucronatus (이하 Bm), B.thailandae (이하 Bt) 선충 3종과 솔수염하늘소 (Monochamus alternatus)와 북방수염하늘소 (M. saltuarius) 2종을 사용하였다. 매개충 번데기에 선충 3종을 10,000 마리씩 단독 또는 혼합접종을 하고, 우화 후 체내 선충 개체수를 조사한 결과, 솔수염하늘소에서는 Bx, Bm, Bt가 각각 2,283마리, 1,575마리, 3,083마리로써 Bt의 침입력이 가장 높게 나타났다. Bx+Bt 처리 시에는 Bx 24%, Bt 76%, Bx+Bm 처리 시, Bx 68%, Bm 32% 비율로 조사되어 Bt>Bx>Bm 순으로 침입력이 강한 것이 확인되었다. 북방수염하늘소 에서 Bx, Bm의 침입력을 비교한 결과 Bx는 2,120마리, Bm 1,730마리로 솔수염하늘소에서와 유사한 결과를 나타내었다. 이로써 선충 종간 침입력은 다양하며 이는 매개충 종과는 무관함을 알 수 있다.

Monochamus saltuarius Gebler (Coleoptera: Cerambycidae) is a well-known as vector species of the pine wood nematode (PWN) in the northern areas of South Korea. In 2017, larval parasitoids of M. saltuarius and their parasitism patterns were investigated in Pinus koraiensis forests with consideration of sentinel logs positions (height: 0 m vs. 1.8 m), distances from the edge to the center of the forest (0, 20, 40, 60, 80m), and damage degrees of the pine wilt disease (infested area, buffer area, and uninfested area). In total six of larval parasitoids were collected: Spathius verustus, Sclerodermus harmandi, Cynopterus flavator, Heydenia testacea, Heydenia sp., Braconidae sp. The parasitism rate to larvae of M. saltuarius larvae was not affected by sentinel log positions. However, the parasitism rate was significantly higher in infested areas compared to the buffer and uninfested areas. In the infested area, the parasitism rate was increased with distance from forest edges.

In 2016 and 2017, population density of Monochamus saltuarius, a vector beetle species of pine wood nematode, was estimated from Korean white pine forests using mark-release-recapture. The beetle was captured by multi-funnel traps with pheromone lure. We collected 1,590, 185, and 268 individuals from Hongcheon (2016), Hongcheon (2017), and Yangpyeong (2017), respectively. Recapture rates in 2016 and 2017 were ranged from 2.38 % to 5.06 %, and estimated population densities during two years were ranged from 4,824 to 13,340 individuals per 1 ha. Because of low recapture rates in both years, population density of M. saltuarius in Korean white pine forests may be over-estimated.

Beetles of the genus Monochamus Dejean (Coleoptera: Cerambycidae) are the most important vectors of the pine woodnematode (PWN), Bursaphelenchus xylophilus (Steiner & Buhrer) (Nematoda: Aphelenchoididae). The most efficient wayto control pine wilt disease is to decrease the population levels of the vector Monochamus beetles. Specific and efficientnatural enemies would be an interesting and environmental-friendly option. From 2016 to 2017, we investigated on thelarval parasitoids associated with M. alternatus Hope and M. saltuarius Gebler using the sentinel logs (Pinus koraiensis)in South Korea. As results of this work, we report two larval ectoparasitoids, Spathius verustus Chao and Cyanopterusflavator (Fabricius) (Hymenoptera: Braconidae) from six survey sites. Each parasitoid was parasitized up to 58.2% and26.3% on 1st and 2nd instar larvae of Monochamus beetles, respectively. These parasitoids are likely to be highly efficientas bio-control agents. Morphological characters with illustration and some biological information of them are provided.

In this study, we isolated and identified an aggregation-sex pheromone from Monochamus saltuarius, the major insectvector of the pine wood nematode in Korea. Adult male of M. saltuarius produces 2-undecyloxy-1-ethanol, which is knownto be an aggregation-sex pheromone in other Monochamus species. We performed field experiments to determine the attractivenessof the pheromone and other synergists. More M. saltuarius adult beetles were attracted to traps baited with the pheromonethan to unbaited traps. Ethanol and (-)-α-pinene interacted synergistically with the pheromone. Traps baited with pheromone+(-)-α-pinene+ethanol were more attractive to M. saltuarius adults than traps baited with pheromone, (-)-α-pinene, or ethanol alone.Ipsenol, ipsdienol, and limonene were also identified as synergists of the aggregation-sex pheromone for M. saltuarius adults.

Monochamus alternatus (M. alternatus) and Monochamus saltuarius (M. saltuarius) are major vectors for Bursaphelenchus xylophilus in South Korea. When an adult, they are easily distinguishable by several morphological classification. However, it is difficult to identification between M. alternatus and M. saltuarius when they are larvae as they have very similar morphological characters. Thus, they are not easily distinguishable without expertise about Cerambycidae taxonomy. Furthermore, during epidemiological investigation, sometimes, adults or larvae would not be founded in death pine trees. For these reasons, in this experiment, we are able to identified between M. alternatus and M. saltuarius by mitochondrial 12S rRNA gene primers that are specific to 12S rRNA gene fragment of M. alternatus using larvae tissue and frass. Moreover, we had examined whether vectors that were already escaped from dead pine tree have Bursaphelenchus xylophilus or not by multiplex PCR using larva frass that was remained in dead pine tree.

Monochamus saltuarius is one of the insect vector of pine wilt disease with Monochamus alternatus. The present study aimed to investigate the dose to induce sterile and the effect of sterility according to the gender of M. saltuarius. As the electron beam irradiation dose increased, the hatchability, adult eclosion rate and longevity of the former mid and late maturation feeding stage of adults was slightly reduced. However, there was no difference between these two adults. In addition, female adults were more sensitive to the electron beam than the male adults. Hatchability of the F1 generation of ♂T × ♀N o r♀T × ♂N (T: 200 Gy electron beam irradiation, N: 0 Gy) was completely suppressed. As electron beam irradiation dose increased, the fecundity of female adults were slightly decreased. Results by comet assay showed that electron beam irradiation induced as dose increased DNA damage in M. saltuarius adults. These results suggest that SIT using electron beam may be useful for control of M. saltuarius.

The longhorn pine sawyers, Monochamus saltuarius and M. alternatus (Coleoptera: Cerambycidae), are vectors of the pinewood nematode Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae), the causal pathogens of pine wilt disease in Korea. Recently, an aggregation pheromone, 2-(undecyloxy)ethanol, identified from M. galloprovincialis and M. alternatus, was shown to be effective for attracting several Monochamus species in Europe, North America, and East Asia. However, the effect of 2-(undecyloxy)ethanol on attracting M. saltuarius remains largely unraveled. In this study, we investigated the abilities of 2-(undecyloxy)ethanol along with host plant volatiles (α-pinene and ethanol) to attract M. saltuarius at a pine forest in Cheongsong, Gyeongsangbuk-do, Korea. Pine trees in the field experiment site were not previously affected by pine wilt disease. The combination of 2-(undecyloxy)ethanol with host plant volatiles was more effective than either of 2-(undecyloxy)ethanol or host plant volatiles for attracting M. saltuarius. Both sexes of M. saltuarius were attracted to traps containing 2-(undecyloxy)ethanol with the host plant volatiles. Our study suggests that the aggregation pheromone in combination with host plant volatiles could be used for detection and population monitoring of M. saltuarius as well as for effective mass trapping in outbreak situations.

북방수염하늘소는 솔수염하늘소와 같이 소나무재선충병을 유발하는 소나무재선충의 주요 매개충으로 소나무류에 막대한 피해를 주고 있다. 북방수염하늘소는 형태적으로 다형성을 나타내는 것으로 보고되었으나, 이들을 구분하는 뚜렷한 표현형이 제시되지는 못한 실정이다. 북방수염하늘소의 종내다양성 조사를 위하여 충북, 경기, 강원지역에서 채집된 표본을 대상으로 미토콘드리아 cytochrome c oxidase 1 유전자의 DNA barcode를 확보하고 계통분석을 실시한 결과 서로 다른 계통을 보이는 두 개의 그룹으로 구분되는 확인 할 수 있었다. 두 개의 그룹은 2.4-2.6의 K2P distance를 나타내었으나 형태적으로 구분되는 특징은 파악되지 않았다. 각 그룹의 북방수염하늘소 수컷의 생식기 검경결과 I 그룹 표본의 파악기 (paramere) 길이가 II그룹의 표본보다 다소 짧고 약간 넓은 차이가 있는 것을 확인하였다. 이와 같은 결과는 두 그룹 간에 북방수염하늘소가 계통적으로 분화가 진행 된 것으로 사료되지만 두 그룹간의 명확한 지역적 분포의 차이가 나타나지는 않았다는 점에서 종 분화의 원인에 대해서는 현 시점에서 판단하는데 어려움이 있으며 향후 다양한 진전된 연구가 필요할 것으로 사료된다.

Monochamus saltuarius, which mediates Bursaphelenchus xylophilus is one of the important vector of pine wilt disease recently. M. saltuarius showed difference with weight, growth, and oviposition according to species of trees. The most feeding amount and feeding area were determined in P. koraiensis. However, M. saltuarius almost did not feed and longevity was observed very short time only for 10 day in Sciadopitys verticillata. Weight, length and head width were measured the highest growth of M. saltuarius in P. koraiensis. Female of M. saltuarius was determined more growing than male of M. saltuarius in all species of trees. Tree preference for oviposition of M. saltuarius was the highest choice in P. densiflora. However, lots of scar for oviposition have observed but M. saltuarius laid less eggs in P. rigida. This result is related to bark thickness of trees. Ovipositional frequency has been consistently maintained to P. densiflora and P. koraiensis at 20 day intervals. In this study, physiological and ecological characteristic of M. saltuarius to preference of trees were researched could be helpful for managing of M. saltuarius.