Entomopathogenic fungi have been known as promising candidates for biological control of insect pests. Recently, researchers consider the fungal thermotolerance in formulations and field applications. In this study, we investigated the production of thermotolerant Isaria javanica and I.fumosorosea conidia through grain-based solid cultures and exposure to light stress. As results, of the ten grain substrates, Italian millet, rice, perilla seed and sesame, rice, sorghum produced highly thermotolerant conidia in the strains. The two strains were exposed to a light stress and showed enhanced thermal stability compared to control, when exposed to 45°C for 2 hours. This work suggests that heatresistant entomopathogenic fungal conidia can be produced by grainbased solid cultures and exposure to light stress.

세계화로 인해 교역 및 여행객의 증가로 외래 병해충의 유입이 증가하고 있고 이들의 유입 및 확산 경로 규명을 위하여 분자 유전학적 분석 방법이 이용되고 있는 실정이다. 본 연구는 외래 해충인 Reticulitermes kanmonensis의 유전적 특성을 분석하기 위한 18개의 초위성체마커(microsatellite)를 이용하여 총 16개 지역(전주, 김제1, 김제2, 군산1, 군산2, 서천, 완주1, 완주2, 완주3, 완주4, 익산1, 익산2, 논산, 일본1, 일본2, 일본3)의 흰개미 244개체를 분석하였다. 집단간 대립 유전자 패턴(allelic patterns)분석결과 일본3 지역의 유전적 다양성이 높게 나타났고 완주2 지역은 다른 지역에 비해 비교적 낮게 나타났다. 집단 간 유전적 거리(Genetic differentiation)는 평균적으로 0.163정도의 유전적 다향성 비율을 나타냈고, 서천과 군산2 지역이 0.048로 낮게, 서천과 일본2 지역이 0.442로 높게 나타나 서천과 군산2 집단이 유전적으로 가깝게 나타나고, 반면 서천과 일본2 집단과는 유전적으로 멀게 나타났다. STRUTURE 분석결과는 클러스터 집단 수가 6(k=6)일때 이상적인 집단 패턴을 나타내었고, 유전적 구조는 A그룹(전주, 김제1, 완주2), B그룹(서천, 군산1, 군산2), C그룹(완주1, 김제2), D그룹(논산, 익산1, 익산2), E그룹(김제1, 완주2, 완주3), F그룹(일본1, 일본2, 일본3)의 6가지의 패턴이 지역별로 분리되어 나타났다.

Japanese pine sawyer beetle, Monochamus alternatus Hope (Coleoptera: Cerambycidae) is considered as a serious pest in pine trees. To develop an eco-friendly strategy to manage this forest insect, we collected entomopathogenic fungi from Korean soil and assessed their virulence against the adults of the insect in laboratory conditions. As a result, two isolates with conidial suspension (1.0×107conidia/ml), showed 87% and 90% mortality 12 days after fungal treatment, respectively. We assessed the potential of the fungi-derived destruxin and protease as additives to the fungal isolates, and they showed insecticidal activity via feeding and spraying treatments. Finally, we produced fungal conidia in massive solid cultures and formulated wettable powders, and now studying optimal conditions of oil-based formulation with two isolates. Based on these results, we are evaluating the control efficacy of the fungal agents against M. alternatus in field conditions.

동남아시아에 발생하던 등검은말벌은 최근 국내 뿐만 아니라 프랑스와 일본, 유럽 전역으로 확산되어 전 세계 양봉 산업에 극심한 피해를 주고 있다. 등검은말벌을 방제하기 위해 다양한 방제 방법들이 연구되고 있으며, 그 중 말벌 유인제에 대해 국제적으로 많은 연구가 진행되어 왔으나 이 역시 지속적인 개발이 필요한 실정이다. 따라서 본 연구에서는 시판 유인제와 최근 (주)다목에코텍에서 새롭게 개발한 신규 개발 유인제에 대한 효능 검정을 수행하였 고 양봉장에 출현하는 국내 발생 말벌속의 발생양상을 조사하였다. 담양 1개소와 곡성 2개소에 기존 유인제과 신규 유인제를 장착한 포획기를 각 3쌍씩 설치하여 2016년 9월부터 11월말까지 주 1~2회 관찰하였다. 그 결과 국내 발생 말벌속 중 등검은말벌(7,787 개체)이 가장 많이 포획되었고, 다음으로 장수말벌, 말벌, 좀말벌, 꼬마장수말벌, 털보말벌 순으로 포획되었다. 두 유인제의 포획력 검정 결과, 신규 개발 유인제가 통계적으로 유의하게(P < 0.01) 등검은말벌 포획력이 높음을 보였다.

갈색날개매미충을 효과적으로 방제하기 위하여 성충이 선호하는 향을 첨가한 황색끈끈이트랩으로 감과 아로니아 과수원에서 성충 포획시험을 2년 동안 수행하였다. ㈜마이크로자임에서 제공한 갈색날개매미충 유인물질은 Methyl salicylate, Phenylethyl alcolol 등으로 조성되었는데 실내시험 결과 93.3%의 유인력을 보였다. 유인물질 도말 황색끈끈이 트랩을 밤과 감 과수원에 설치하여 10일 후 유인충수를 조사한 결과 황색끈끈이트랩 대비 유인물질 도말 황색끈끈이트 랩이 2~3배 많이 포획되었다. 2017년에는 높이 180cm이며 가로 40cm, 세로 25cm 의 갈색날개매미충 포획용 끈끈이트랩 6장을 지지할 수 있는 트랩 거치대를 제작하여 발생밀도가 높은 전남 구례의 감 과수원과 광주 아로니아 과수원에 설치하여 10일 간격으로 트랩을 교체하며 성충 포획량을 조사하였다. 성충은 8월 중하순에 가장 많이 포획되었으며 기온이 낮아지는 10월에는 포획량이 급격히 줄어들었다. 트랩당 총 포획량이 감 과수원은 12,674마리, 아로니아 과수원은 9,251마리였다. 갈색날개매미충 방제에 유인물질 도말트랩이 효과적일 것으로 판단된다.

The oriental fruit fly, Bactrocera dorsalis (Hendel), has potential of serious damage to various vegetables or fruits, especially genus of Citrus, such as mandarin orange and tangerine in Korea, where its larvae do damages. Animal and Plant Quarantin Agency of Korea and Animsl Systematics Laboratory of Kunsans National University have collected the samples of oriental fruit fly in East Asian countries, Vietnam, Philippines, Myanmar, China, Cambodia, India Nepal and Laos. To confirm genetic differences and structure of B. dorsalis population samples collected from those countries, we analyzed 192 individuals from 28 locations over 7 countries using 15 microsatellite loci. In total samples, number of different alleles, number of effective alleles and Shannon's Information Index were 6.421±0.364 (standard error, SE), 3.664±0.137 (SE) and 0.902±0.030 (SE), respectively. Grand means (±SE) of observed and expected heterozygosity over all loci and populations were 0.534 (±0.018) and 0.597 (±0.017), respectively. Among all populations, Fst values ranged from 0.016 to 0.705 with averaging 0.194 (±0.026).

외래 병해충의 유입이 증가 하고 있고 이들의 유입 및 확산 경로 규명을 위하여 분자 유전학적 분석 방법이 이용되고 있는 실정이며, 본 연구는 외래 해충인 Reticulitermes kanmonensis의 유전적 특성을 분석하기 위한 초위성체마 커(microsatellite)를 문헌을 통해 탐색하였고, NGS(Next-Gen Sequencing) 기술을 통해 새로운 초위성체마커를 개발하였 다. 문헌을 통해 Reticulitermes속에서 개발된 마커29개와 NGS를 통해 선발된 25개의 마커를 탐색 하여, 이중 증폭 및 유용성이 있는 18개의 마커를 선정하였다. 선정된 단일 마커들을 이용하여 6개의 multiplex PCR set 및 증폭 조건을 수립하여 집단유전학 분석에 활용하고자 한다.

Beauveria bassiana (Bb) is a potential biopesticide against western flower thrips. To understand molecular characteristics of two Bb isolates (ERL836 and JEF-007), whole genome sequencing and RNA-seq were performed. The whole genome of Bb ERL836 was sequenced (3,934,801,443 bp) using Pacbio sequencing and 15 contigs were analyzed. To understand the molecular mechanisms of pathogenicity in two Bb genome (before infection and after infection), next generation sequencing (NGS) was analyzed to compare transcriptomes. A result of differentially expressed gene (DEG) showed that 2,689 contigs were up-regulated and 2,619 contigs were down-regulated. Randomly selected five genes were validated to be highly up-regulated. This work can provide an understanding of the interaction between Bb and westetn flower thrips.

Japanese pine sawyer, Monochamus alternatus Hope (Coleoptera: Cerambycidae) in forest is considered as a serious forest pest in pine trees. In this study, we collected entomopathogenic fungi from soil and assessed their virulence against the adults of the inset using a spray method in laboratory condition. Two entomopathogeinc fungi isolates showed high virulence against the adults. In the concentration of 1.0 × 107conidia/ml, the mortality rate of the adults were 53% and 60%. In semi-field condition, one isolate showed a virulence of 60% against the adult. Consequently, we confirmed the possibility of the fungal isolates in controlling the beetles. In near the future, we will investigate several factors which is possibly related to the control of the forest insect pest using entomopathogenic fungi in field conditions, given the importance of fungal formulation and practical application methods.

The hard tick, Haemaphysalis longicornis (Ixodida: Ixodidae) is one of the vectors of severe fever with thrombocytopenia syndrome virus (SFTSV) causing in humans, however little consideration was given to the biological control of the pest. Therefore, this study provides a screening method to select entomopathogenic fungi, having high virulence against H. longicornis. The virulence test was conducted by dipping method with a conidial suspension (1×107 conidia/ml). As a result, cadavers of H. longicornis infected with entomopathogenic fungi were obtained by this method. Based on this results, we selected several isolates having high virulence to H. longicornis. We suggest that, selected isolates in this study can be used for the control of H. longicornis.

Entomopathogenic fungi have been known as promising candidates for biological control of insect pests. Recently, researchers consider the fungal thermotolerance in formulations and field applications. In this study, we investigated the production of thermotolerant Isaria javanica and I.fumosorosea conidia through grain-based solid cultures and exposure to light stress. As results, of the ten grain substrates, Italian millet, rice, perilla seed and sesame, rice, sorghum produced highly thermotolerant conidia in the strains. The two strains were exposed to a light stress and a heat stress. And they showed enhanced thermal stability compared to control, when exposed to 45°C for 2 hours. This work suggests that heat-resistant entomopathogenic fungal conidia can be produced by grain-based solid cultures and exposure to light stress.

Melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae) is a serious insect pest of various crops in the world. The management of this pest mainly have relied on chemical agents. However, the overuse of chemical agents for long times causes insect resistance, and negative effects on environment. Therefore, alternative control methods, such as biological control, that are less harmful to the environment and have different mode of action are needed to control this pest. In this study, we isolated entomopathogenic fungi from Korean soil, and characterized them via morphological and molecular identifications and pathogenicity check against Tenebrio molitor larvae. The isolated fungi were subjected to virulence assay against T. Palmi with a conidial suspension of 1×107 conidia/ml in laboratory conditions. This entomopathogenic fungi library would be a good resource to select effective strains for the control of T. palmi in fields.

Entomopathogenic fungi play an important natural role in regulating their insect host populations, and their ecology was also associated with plant and soil. These microorganisms have been living by reacting to insect, plant and environmental factor. The advanced bioinformatics technology such as next-generation sequencing and RNA sequencing has revolutionized in understanding of entomopathogenic fungi. Recently studies provided a lot of information on evolutionary relationships and virulence-related characteristics. We are starting to know where these microorganisms from is, and how they live in nature. The bioinformatics technology will give us further our understanding of the natural roles of these fungi in nature.

In the 21st century, the risk of the exotic pest being invaded is increasing due to the rise of trading activities. Oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), has been considered to very destructive invader as it is highly intrusive and has a wide host range. In this study, 2,299 samples were collected from 88 locations in 12 countries by quarantine and investigation. Among them, 608 individuals were used for COI DNA barcoding analysis based on Neighbor Joining method with P-distance model. Population genetics analysis was conducted for 510 individuals selected from 47 locations of 12 Southeast Asian countries using 15 microsatellite markers. COI DNA barcoding results showed that B. dorsalis did not support any clade as a geographical isolation but almost indicated mixed populations of each country. Population genetics analysis showed similar pattern of genetic structure between neighboring countries across borders. Most domestic quarantine groups were more similar in genetic structure to Taiwan, China and Thailand in the order of appearance.

We present a study of the inexplicit connection between radio jet activity and γ-ray emission of BL Lacertae (BL Lac; 2200+420). We analyze the long-term millimeter activity of BL Lac via interferometric observations with the Korean VLBI Network (KVN) obtained at 22, 43, 86, and 129 GHz simultaneously over three years (from January 2013 to March 2016); during this time, two γ-ray outbursts (in November 2013 and March 2015) can be seen in γ-ray light curves obtained from Fermi observations. The KVN radio core is optically thick at least up to 86 GHz; there is indication that it might be optically thin at higher frequencies. To first order, the radio light curves decay exponentially over the time span covered by our observations, with decay timescales of 41185 days, 352±79 days, 310±57 days, and 283±55 days at 22, 43, 86, and 129 GHz, respectively. Assuming synchrotron cooling, a cooling time of around one year is consistent with magnetic field strengths B ∼ 2 μT and electron Lorentz factors γ ∼ 10 000. Taking into account that our formal measurement errors include intrinsic variability and thus over-estimate the statistical uncertainties, we nd that the decay timescale  scales with frequency τ ν - 0.2. This relation is much shallower than the one expected from opacity effects (core shift), but in agreement with the (sub-)mm radio core being a standing recollimation shock. We do not find convincing radio flux counterparts to the γ-ray outbursts. The spectral evolution is consistent with the `generalized shock model' of Valtaoja et al. (1992). A temporary increase in the core opacity and the emergence of a knot around the time of the second -ray event indicate that this γ-ray outburst might be an `orphan' are powered by the `ring of fire' mechanism.