• 한국전통조경학회지
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• 제35권2호
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• pp.77-86
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• 2017

부산 범어사 등나무군락지에 대한 개체군생태학 연구가 이루어졌다. 연구지역은 1966년에 천연기념물 제176호로 지정되어 보호되고 있는데, 국내에서 자생적 기원을 가지며 등나무가 대규모의 군락을 이루고 있는 경우는 매우 희귀하여 높은 학술적 가치를 지닌다. 그러나 범어사 등나무군락은 군락지 내의 등나무 분포 현황 및 생태에 대한 해상도 높은 연구는 이루어지지 않았다. 본 연구는 등나무군락 내의 개체 분포 현황과 개체군 특성을 확인하고, 보존방안을 논의하는데 그 목적이 있다. 현장 조사를 통해 범어사 등나무군락과 그 일대를 대상으로 등나무의 분포, 근원직경, 감고 올라가는 방향 및 식물종과 연구지역 내 식물상에 대한 현황을 파악하였다. 그 결과, 연구지역 내 등나무 개체 수는 총 1,158개체가 확인되었고, 등나무의 근원직경은 평균 69.0 mm (${\pm}45.5$), 최대 365 mm로 나타났다. 감는 방향은 시계방향으로 감는 등나무뿐만 아니라 반시계방향으로 감는 등나무 40개체가 확인되었다. 등나무의 등반식물종은 28분류군으로 확인되었고, 그 중 동종(同種)인 등나무를 가장 선호하는 것으로 나타났다. 등나무군락은 계곡부에 인접하여 분포하고 있는 것으로 확인되었으며, 지속적인 교란에 의해 유지 발달하고 있는 군락으로 파악되었다. 현존식생도를 통해 계곡림에 76.6%의 개체가 분포하는 것으로 확인되었으며, 개서어나무-이대우점림, 칡군락, 소나무우점림 등에서는 상대적으로 분포가 배제되는 것으로 밝혀졌다. 본 연구는 확산되어가고 있는 등나무개체군과 최대 근원직경을 가지는 등나무의 보호, 지역 서식처 보존 등을 위하여 지속적인 모니터링을 통한 후속 연구를 진행함과 동시에 천연기념물 제176호 보호 지역의 수정과 서식처에 대한 간섭을 최소화하기 위한 방안의 마련 등을 제안하였다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.132.1-132
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• 2003

A Phoma sp. was detected on rice seeds and was identified as Phoma sorghina (Sacc.) Boerema, Dorenbosch ＆ Van Kesteren based on their morphological and cultural characteristics. On oatmeal agar, pycnidia were abundant, solitary, scattered or gregarious, subglobose to flask-shaped, usually with a distinct neck and ostiole, glabrous, blackish-brown, 55∼185 ${\times}$ 40∼170 $\mu\textrm{m}$ in size. Conidiogenous cells were monophialidic, hyaline, subglobose to ampulliform, 3∼5 $\mu\textrm{m}$ in diameter. Conidia were ovoid to ellipsoidal, hyaline, unicellular and measured 3.5∼6.0 ${\times}$ 1.5 ∼3.0 $\mu\textrm{m}$ (usually 4.0∼5.0 ${\times}$ 2.0∼2.5 $\mu\textrm{m}$) in size. Chylarnydospores were variable, uni- or multicellular, intercalary or terminal, solitary or in chains, dictyosporous or botryoid. NaOH spot test was positive on malt extract agar. This is the first report of P. sorghina identified on rice seeds in Korea.

• Animal cells and systems
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• 제6권1호
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• pp.19-22
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• 2002

Life table studies were conducted in the laboratory for the eulophid gregarious pupal parasitoid, Tetrastichus sp., on Hyphantria cunea Drury at a constant temperature of 28.2$\pm$2$^{\circ}C$, 50-60% RH to evaluate their impact on the host and their potential biological control. Development of immature stage took 20.1$\pm$2.7 d: adult females lived for 23.2$\pm$2.2 (range, 16-27)d and produced a mean of 53.6$\pm$26.6 adult progeny per female, with a sex ratio of 1: 9.5 (M:F). The intrinsic rate of natural increase (r$_{m}$) was 0.178/ female/day; the net reproductive rate (R$_{o}$), 46.74; the capacity for increase (r$_{c}$) 0.177; the finite rate of increase (λ) 1.19/female/day; thus each female contributed 46.74 individuals to the population in a mean generation time of 21.6 d. Biological factors in determining the life history trait variation of the parasitoid were discussed.d.d.d.

• 인터넷정보학회논문지
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• 제18권5호
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• pp.103-112
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• 2017

Work engagement and job burnout are crucial problems in Korea, particularly in the business environment, and they also indicate people's motivation. Online-based teams in e-business also have these issues. Especially the role of the leader in this new type of teams is more crucial for members' motivation, behavior, and performance. Contingency leadership theories posit that different situations need different traits or behaviors of a leader. For an online-based team, which is internet-based team in e-business, a leader should use specific communication strategies to enhance a team's performance and members' motivation. In an online-based team and an offline-based team, the ways in which leaders motivate members will be different. This paper suggests particular communicative strategies for leaders of online situations. Online-based team members communicate using mobile phones or IT tools, and leaders mayinfluences members in virtual meetings. Moreover, online-based leadership needs to be more entrepreneurial and risk encouraging, and less conservative than offline-based leadership. In addition, online-based leadership should be energetic, decisive, adaptable, and inspiring, and furtherutilize communication tools such as being more gregarious/talkative, assertiveness, linguistic diversity and affect. This paper explains the roles of communicative elements such as coordination, expression, direction-giving/uncertainty reduction, empathy, meaning-making, satisfaction, and competence to decrease job burnout and to increase work engagement. The purpose of this study is to suggest communication strategies' differentiated influences on work engagement and job burnout in an online-based team.

• Journal of Forest and Environmental Science
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• 제14권1호
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• pp.128-137
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• 1998

담팔수깍지벌레의 천적 종류는 1차 기생벌 6종, 2차 기생벌 3종, 포식성 무당벌레 5종 및 풀잠자리류 1종등 총15종이 확인(確認)되었다. 1차 기생벌 가운데 Aneristus ceroplastae, Microterys flavus, Coccophagus yoshidae의 밀도가 높았으며, 최 우점종은 Aneristus ceroplastae이었다. Aneristus ceroplastae와 Coccophagus yoshidae는 단기생성(單寄生性)의 내부기생자(內部寄生者)이었으며 Microterys flavus는 다기생성(多寄生性) 내부기생자(內部寄生者)이었고 2차 기생벌 가운데 최우점종인 Tetrastichus sp.는 Aneristus ceroplastae와 Microterys flavus의 용에 기생하는 단기생성(單寄生性)의 외부기생자(外部寄生者)이었다. 또한 주요 기생벌의 기생율(寄生率) 및 계절적(季節的) 발생소장(發生消長)을 구명(究明)하였다. 포식성(捕食性) 천적(天敵)은 Rhyzobius forestieri와 Chilocorus kuwanae가 우점종이었으며 이들 종(種)에 대한 발생소장(發生消長) 및 포식량(捕食量)을 구명(究明)하였다. 특히 Rhyzobius forestieri는 담팔수깍지벌레를 포식하는 종으로 일본 구주지방에서 처음 기록(記錄)하였다.

• 한국응용곤충학회지
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• 제41권2호
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• pp.99-105
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• 2002

Tetrastichus sp.는 미국흰불나방의 번데기 기생벌로서, 1개의 숙주에 여러마리의 자손을 번식하는 집단 기생벌이며, 일년에 여러 세대 발생한다. 작잠, 신생아용 분유, 난황, 로얄젤리 등을 주요성분으로 기생벌의 인공먹이를 조성하였으며, polypropylene필름으로 번데기형태를 만들어 인공숙주로 사용하였다. 인공숙주에서 발육한 기생벌은 자연숙주에서 자란 기생벌보다는 크기가 작았으나, 계대 사육으로 번식 가능한 자손을 생산하였다. 인공숙주에서 발육한 in vitro 2세대의 생물학적 특성은 in vitro 1세대보다 훨씬 개선 었다. 평균 자손 수, 산란기간, 수명 등은 in vitro 에서 45.7,7.8, 13.8일 이었고 암컷 편중의 성비 76.9%를 나타내었다. 이러한 결과는 Tetrastichus sp.가 in vitro 대량사육에 적합한 기생벌임을 보여준다.

• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.

• Journal of Ecology and Environment
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• 제47권4호
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• pp.250-260
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• 2023

Background: Crabgrass (Digitaria ciliaris, Poaceae) is a globally distributed weed, including in Afro-Eurasia, America, and Australia. As a highly gregarious plant, crabgrass is an important habitat for a diverse array of insects, and a potential habitat for agricultural pests. To compare the insect communities associated with the crabgrass community, insects were sampled using sweep sampling (100 sweeps per sample) at five sites, including Daejeon (Daejeon and Gap rivers), Anseong, Namhae, and Inje, with a focus on the Daejeon River. Results: A total of 5,888 individual insects belonging to eight orders, 42 families, and 115 species were collected from the five sites. Both the number of species and individuals of Hemiptera were the highest at all of the sites. In the present study, 73% of the insect population fed on D. ciliaris as a host plant. The dominant species in the D. ciliaris community was Laodelphax striatellus (Delphacidae), being ubiquitous at all the sites which showed a high abundance of rice pests in the communities and the suitability of D. ciliaris as an alternative host plant for them. The Shannon-Wiener diversity index was highest in Inje on 17 September (2.88), and the Chao1-bc diversity index was highest in the Gap River on 5 September (80). The sampling efficiency of 100 sweep samples (sample coverage) was calculated to be as high as 90%. The results of the samples taken from September to November in the Daejeon River showed that the number of species and individuals decreased gradually over time, and the number of dominant species decreased sharply between September and October. Similarity analysis indicated that sampling dates that were closer together yielded sampled assemblages with higher faunal similarity. In addition, in each sampling, the difference in the minimum temperature during the two-week period prior to sampling and faunal similarities were negatively correlated. Conclusions: This study provides foundational data that could enhance our understanding of insect diversity in D. ciliaris. The data can facilitate ecological conservation and management of Korean grasslands generally, as well as identification of potential pests that may disperse from D. ciliaris communities to nearby farmland.

• 한국응용곤충학회지
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• 제49권2호
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• pp.159-162
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• 2010

잣나무솔잎벌(Diprion hani Smith and Cho)은 2007년 최초 발생이 보고되었으며 신종으로 기재되었다. 2007년 9월초 대발생 후 밀도가 극히 낮아져 2008년 야외조사에서 잣나무솔잎벌 개체는 거의 채집되지 않았다. 본 연구는 잣나무솔잎벌 대발생 지역 특성 구명을 위해 피해지 위치정보, 우점 수종, 온도, 강우 등 환경 인자들이 조사되었다. 발생지역은 경기도 양평, 강원도 횡성, 충북 제천 3지역 모두 중부내륙지역 반경 25 km에 모여있었다. 피해수종은 잣나무(Pinus koraiensis Sieb. & Zucc.)였으며, 발생지역 모두 인공 조림지였다. 2007년도 3지역의 잣나무조림지의 온도는 지난 30년간 월 평균 평균온도보다 $1.3^{\circ}C$ 높았고 연간강우량은 384 mm 높았다. 또한 솔잎벌과 종들의 고치에 다기생하는 것으로 알려진 가시꼬리좀벌(Monodontomerus dentipes (Dalman))이 잣나무솔잎벌에 기생함이 밝혀졌다.

• 한국산림과학회지
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• 제4권1호
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• pp.9-13
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• 1965

Powdery mildew of Ailanthus altissima Sw. was first reported by J.S. Park in Korea, 1961. According to his report, this disease was found on the leaves of this tree species collected in Jeongup, 1957, and in Taejon, 1958. He described morphological characters of this pathogen and described also that the causal fungus may be closely related with Phyllactinia corylea. This disease which appears dusty grayish yellow molds under surface of leaves was collected again by the author in Kwangju, 1962. The present works were undertaken to make clear the species of causal fungus by means of the morphology and pathogenecity. According to the following results, the pathogen was identified as Phyllactinia corylea (Pers.) Karst. Morphological characters of the fungus Mycelia persistent or more or less evanescent; matured conidia solitary, aseptate, short-clavate to clavate to clavate, hyaline or yellowish, granulate, $44.6-89.2{\times}9.3-24.2{\mu}$, average $64.8-17.8{\mu}$ in size; conidiophores elongate clavate or columnar, hyaline, 2-3 septate, $122.8-346.0{\times}3.7-7.4{\mu}$, average $208.8{\times}6.3{\mu}$; per-thecia usually scattered, rarely gregarious, dark brown to black, depressed globose to globose, $223.2-297.6{\mu}$, average $267.8{\mu}$ in diameter; appendages 12-19, usually 15 in number, hyaline, straight, needle-shaped, sharply pointed at the apex and bulbous at the base, aseptate, $93.0-310.0{\times}5.0-8.0{\mu}$, average $173.3{\times}6.4{\mu}$ in size; asci elongate ellipsoidal to broadly clavate, hyaline, more or less stalked, 8-13 in number, $68.5-76.6{\times}26.1-34.2{\mu}$, average $71.4{\times}29.0{\mu}$ in size; ascospores 2-4, usually 2 in number, hyaline or yellowish, aseptate, ellipsoidal or ovate, $27.7-34.2{\times}14.7-17.9{\mu}$, average $25.5{\times}13.9{\mu}$ in size. Pathogenicity of the fungi In order to make clear the species of the fungus and the pathogenic differences of Phyllactinia fungi which are collected around the contaminated area and seemed to be related to Ailanthus powdery mildew, some inoculation experiments were performed. 1. Cross inoculation to several tree species with their pathogen: Tested materials; Phyllactinia in question on Ailanthus altissima Sw. Ph. fraxini (DC.) Homma. On Alnus firma S. et Z. Ph. moricola (P. Henn.) Homma on morus alba L. According to the results of the experiments, the reactions were all negative with the exception of the original hosts of tested fungi. 2. Inoculation to Picrasma ailanthoides Planch. : The appearance of symptom on the leaves of P. ailanthoides is not distinct, but more or less mycelial growth. Therefore, under the optimal condition in glass chamber, it may be possible to success artificially.