알파 프로테박테리아(α-proteobacterium)인 볼바키아(Wolbachia) 세균은 절지동물 세포내의 중요한 공생균 중의 하나이다. 그람 음성 세 균인 이 공생균은 기주동물의 여러 생물적 과정에 관여하고 있으며, 현재 생물적 방제 수단으로 주목 받고 있다. 볼바키아는 기주 세포의 세포질에 서식하는 세균인데 암컷을 통하여 세대간 전염된다. 볼파키아의 감염 개체 밀도를 높이기 위해 기주의 생식방식을 조작하는 다양한 전략을 발달시 켰다. 볼바키아 유전자형 계통은 볼바키아 표면 단백질(WSP)의 고변이영역 아미노산 서열과 복합좌위 서열 타이핑(Multilocus sequence typing, MLST)으로 결정된다. 상이한 유전계통 판별은 wsp, 16S rRNA, ftsZ, gltA, groEL 등 유전자 분자표지를 이용하게 된다.. 이 계통 볼바키아 세균과 그들의 우월한 표현형이 농업해충과 인간의 질병매개 곤충에 대한 방제 프로그램에서 이용 가능성이 고려되고 있다. 볼바키아 표현형들은 세포질불일치(cytoplasmic incompatibility, CI), 단성생식 유도(parthenogenesis induction, PI), 여성화(feminization, F), 수컷치사(male killing, MK) 등을 유발하는 것으로 알려져 있다. 기타 볼바키아 세균의 농업과 위생곤충 방제 프로그램에서 응용 방안을 고찰하였다.
Shin, Yu-Ri. 2015. “Nonverbal Discourse Strategies of Korean TV Talk Show Hosts: Focus on ‘Nodding’ and ‘Bending’”. The Sociolinguistic Journal of Korea 23(1). 115~143. As our speech builds on verbal as well as nonverbal elements, we perform discourse strategies through both of them in interaction. This study takes a closer look at the nonverbal strategies performed during talk show discourse as seen on Korean television. By taking into account the sociocultural context on which both talk show hosts and guests mutually rely in their interaction, the paper examines how this shared pool of sociocultural resources affects the discourse strategies of the hosts. This holds particularly true for Korean TV talk shows, since the social relationships, from which the discourse participants draw, is defined and reflected in the shows' semi-institutional character. Throughout the show, the host makes use of nodding and bending on an interpersonal, semantic, and structural level. In this order, such discursive functional devices serve a distinct politeness strategies and can, therefore, be determined as discursive strategies.
싸리수염진딧물(Aulacorthum solani) 방제를 위해 기생성 천적으로 국내에서 선발한 목화검정진디벌(Ephedrus plagiator)과 외국에서 판매 되고 있는 진디벌(Aphidius ervi)을 비교 조사하였다. 성충 수명과 산란 기간, 머미수, 우화충수 등에 대한 우열성을 싸리수염진딧물과 완두수염진 딧물(Acyrthosiphon pisum)을 대상으로 온도 15, 20, 25, 30℃와 광주기 16(L) : 8(D)의 조건에서 조사하였다. 성충 수명은 15℃에서 목화검정 진디벌이 싸리수염진딧물에서 5.9일로 진디벌 3.6일에 비해 2.3일 길었다. 산란 기간도 15℃의 싸리수염진딧물에서 목화검정진디벌이 5.3일인 반면, 진디벌은 2.2일로 상대적으로 짧았다. 싸리수염진딧물에서 목화검정진디벌과 진디벌의 머미수는 목화검정진디벌이 15, 20, 25, 30℃에서 각각 71.5, 41.0, 15.7, 7.7개로 진디벌의 22.1 16.3 6.2, 0.4 보다 많이 기생하는 것으로 나타났다. 반면에 완두수염진딧물에서 목화검정진디벌 의 머미수는 70.3, 69.8, 34.3, 8.4개로 93.4, 71.2, 34.8, 14.5로 조사된 진디벌의 머미수보다 낮았다. 싸리수염진딧물에서 목화검정진디벌의 우 화충수는 42.1, 36, 11.6, 0로 나타나 30℃의 높은 온도에서는 우화하지 않은 것을 알 수 있었다. 진디벌의 경우에는 우화 개체수가 각 온도에서 19.6, 13.5, 3.7, 0.1로 나타나 목화검정진디벌에 비해 상대적으로 적게 우화한 것으로 조사되었다. 두 종의 비교결과, 싸리수염진딧물에서는 목 화검정진디벌이, 완두수염진딧물에서는 진디벌이 우수한 것으로 조사되었다.
The genus Diadegma is a well known parasitoid group and some are known to have symbiotic virus, PDV. A novel IV was discovered from the calyx of D. fenestrale female. D. fenestrale has more than two hosts, including PTM and DBM. The oviposition and survival rate results showed that D. fenestrale preferred PTM to DBM as hosts. Nevertheless, the developmental period and morphology of D. fenestrale were not significantly different between PTM and DBM. To identify these phenomena, DfIV genome expression patterens were compared between PTM and DBM under various conditions. DfIV genes were more widely expressed in PTM than in DBM after parasitized by D. fenestrale, particularly at the initial point. In addition, large numbers of DfIV genes were expressed only in PTM and they showed differential expression patterns between two lepidopteran hosts. This DfIV genome expression plasticity showed a dependency on the lepidopteran host species and parasitization time, suggesting that it may contribute to the parasitoid survival rate increase. This may be one of the key elements that determine the symbiotic relationship between PDV and parasitoid.
The Diadegma fenestrale is known as parasitoid on potato tuber moth, Phthorimaea operculella and diamondback moth, Plutella xylostella. The Diadegma genus is reported to have symbiotic virus, ichnovirus, D. fenestrale Ichnovirus (DfIV) was identified from this species which is a first report. DfIV showed typical ichnovirus shape with two membranes surrounding the virus capsid. To identify DfIV genes, whole genome sequencing based on GS-FLX was conducted using purified total DfIV genomic DNA extracted from D. fenestrale calyx. About sixty ORFs were analyzed and several typical ichnovirus gene families were detected such as cys-motif, repeat element, vinnexin and vankyrin. Present study was focused on the gene expression patterns in two different lepidopteran hosts.
We present the result of our near infrared J- (λ=1.25μm), H- (λ=1.63μm), and Ks-band (λ=2.14μm) imaging of ultraluminous (LI > 1012L⊙) and uminous(LIR=1011−12L⊙) infrared galaxies (ULIRGs and LIRGs), to investigate their relationship through properties of their host galaxies. We find that (1) for single-nucleus ULIRGs and LIRGs, their spheroidal host galaxies have similar properties, but ULIRGs display a substantially higher level of nuclear activity than LIRGs, suggesting that their infrared luminosity difference comes primarily from the different level of current nuclear activity. We infer that LIRGs and ULIRGs have similar progenitor galaxies, follow similar evolutionary processes, and may evolve into optically-selected QSOs. (2) Largely-separated multiple-nuclei ULIRGs have significantly brighter host galaxies than single-nucleus ULIRGs and LIRGs in Ks-band, indicating that multiple-nuclei ULIRGs have a bias towards mergers of intrinsically large progenitor galaxies, in order to produce high infrared luminosity (LIR > 102L⊙) even at the early merging stage. (3) We derive dust extinction of host galaxies of ULIRGs and LIRGs to be AV ~ 14 mag in the optical or quivalently AK ~ 0.8 mag in the near-infrared Ks-band, based on the comparison of host galaxy's uminosities in the J-, H-, and Ks-bands.
We present a list of Korean fungivorous Tenebrionidae associated with higher fungi (Basidiomycetes). Most fungivorous tenebrionids are associated with the order Aphyllophorales. A total of31 Tenebrionid species (both adults and larvae) belonging to four tribes (Bolitophagini, Toxicini, Scaphidernini, and Diaperini) are presented in our checklist. Of these, 62 percent are obligate mycetobionts, In addition, 42 fungal hosts of fungivorous tenebrionids are presented. Both thetenebrionids and the fungal hosts reported here are found throughout Korea.
The parasitism, development time, hatchability, and progeny production of Trichogramma chilonis(TC) females developed in eggs of Helicoverpa assulta (HAs), Cadra cautella (CC), and Helicoverpa armigera (HAr), repectively, were compared with those developed in reciprocal eggs at constant temperatures of 25±2℃ and relative humidity of 50~70% under 16L-8D. Developmental performances of TC reared in each of the three hosts on the following hosts(host tested) appeared differently, and were affected most by the size of the proceeding hosts and test host. Among the parameters parasitism and progeny production were affected more than others. Parasitism was significantly different between the treatments, lowest in CC-HAr(10.1±2.05%) and highest in HAr-HAs(47.0±2.09%), and the hatchability showed similar pattern. Development time as well was shortest in the CC-HAr where previous host is smallest and test host is biggest. The highest number of progeny production of TC was observed in HAr-HAs(93.9±6.87 wasps), and the lowest was CC-HAs(18.4±6.36 wasps).
벼 흰빛잎마름병균의 10균주(I군 3균주, II군 4균주, III군 3균주)를 저항성이 서로 다른 벼품종 '밀양 23호'(김남풍군), '유신'(황옥군), '통일'(Rantaiemas군)의 유묘기와 분얼초기, 최고분얼기, 지엽기에 각각 접종하였다. 그 결과 1) 병원성 발현의 양상이 균주 간 매우 다양하였다. 2) 특히 II군의 균주들은 같은 군균내에서도 변이가 매우 큰 것으로 나타났다. II군은 더 많은 균형으로 세분될 수 있었다. 3) 생육시기 별로 병원성 발현 양상이 달랐으며, 대체로 지엽기 이후 높은 발병을 나타내었다. II군중 G 7716균주는 출수이후에야 비로소 '유신'품종에 발병을 일으킬 수 있었다. 4) 통계분산분석(ANOVA) 결과, 각각 다른 균형의 균주, 품종, 생육시기가 발병정도의 분산에 주요인으로 작용하였고, 균주와 품종간의 상호작용(interaction)에 유의성이 있었으나 다른 요인간에는 없었다.