• 한국수산과학회지
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• 제56권5호
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• pp.684-690
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• 2023

This study was conducted bimonthly from February to December 2021 to reveal the ecology of Sargassum thunbergii in the intertidal zone along the coasts of Korea. Separate surveys on the period of embryo formation were conducted from February 2021 to December 2022. The growth of S. thunbergii began to increase in February, reached a maximum in June, and was at a minimum in October. Air vesicles were formed from February to June, April to August, and February to August on the east, west, and south coasts, respectively. Receptacles were observed from April to June on the east coast, but from April to August on the west and south coasts. The earliest release of embryos was observed in late May 2022 on the south coast, followed by early June on the east and west coasts. The average size of leaves, stems, and air vesicles was maximum on the east coast and minimum on the west coast, whereas leaf and internode intervals were maximum on the west coast and minimum on the east coast. Plant length, biomass, and the number of branches showed maximum values in the south coast and minimum values in the east coast.

• Journal of Forest and Environmental Science
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• 제33권3호
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• pp.243-255
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• 2017

Plants planted in the green-roofed areas in Busan and Jinju were surveyed. The woody plants investigated in this study were classified into 52 families and 156 species, and the herbaceous plants were classified into 30 families and 97 species. Woody plants mainly planted were Rhododendron yedoense var. poukhanense, R. indicum, C. kousa, P. mume, and E. alatus. However, Pinus spp. were planted in all areas. The main herbaceous species planted were Sedum kamtschaticum, S. takesimense, S. middendorffianum, T. quinquecostatus var. japonica, and A. spathulifolius Maxim. According to surveying the distribution of woody plant pests, they could be classified into six orders, 24 families, and 46 species that usually appeared from April to October but especially between June and September. We investigated 39 insect species in relation to pest damage to leaves, 21 insect species in relation to that of branches, and 39 insect species in relation to that of stems of woody plants.

• 한국수학사학회지
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• 제27권3호
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• pp.183-195
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• 2014

In mathematics a prime number is the natural number that has no positive factors other than 1 and itself. As natural numbers greater than 1 can be factored characterized by prime numbers, identities of a culture could be understood if its cultural phenomena are analyzed through cultural prime numbers(CPN). It is not easy to resolve cultural phenomena into CPN and analyze them through CPN due to complexities of culture. Though it is difficult, however, it is not impossible. For CPN keeps relative independence in the context of history and thought. We call 2, 3 and 5 as CPN: 2 is representative of Yin and Yang theory, 3 of Three Principles theory, and 5 of Five Elements theory. We argue that the Ten Celestial Stems and the Twelve Earthly Branches, the core principles in the oriental tradition, could be factored by the CPN. Analyzing Sil-Hah Woo's arguments, we discuss that the CNP 3 achieved more qualitative valuation than the others in Korean culture.

• The Plant Pathology Journal
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• 제17권4호
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• pp.222-226
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• 2001

In 1997, 103 isolates of Verticillium were obtained from roots and stems of tomato plants showing wilt symptoms in greenhouses in eight areas of Korea. Out of these isolates, 75 were edintified as V. dahliae while 28 were identified as V. albo-atrum based on their morpho-logical and cultural characteristics. Both Verticillium species produced colonies with conidiophores, which were more or less erect, hyaline, with verticillate branches, and with 3-4 phialides at each node. V. dahliae produced microsclerotia, while V. albo-atrum produced resting dark mycelium. Optimum temperatures for mycelial growth of V. dahliae and V. albo-atrum on PDA were 22 and $26^{\circ}$, respectively. Mycelial growth of V. albo-atrum was slower than that of V. dahliae. Pathoge-nicity tests revealed that tomato cvs. Zuikoh No. 102, Kyoryokubeiju No. 2, Zuiken, Kagimuza, and Momotaro were susceptible to V. albo-atrum, while cvs. Zuikoh No. 102 and Kyoryokubeiju No.2 were susceptible to V. dahliae.

• 식물병연구
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• 제15권3호
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• pp.259-261
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• 2009

경기도 가평과 강원도 영월에서 포도나무 가지가 수침상으로 물러지고 시들어 죽는 증상을 관할하고 병원균을 분리였다. 병원균의 균총은 PDA 배지에서 처음에는 무색이었으나 배양기간이 길어짐에 따라서 흰색을 거쳐 연한 초콜릿색을 나타내었다. 균핵형성 적온은 $20^{\circ}C$이었으며, 균핵을 멸균한 모래의 1~2 cm 깊이에 매몰하고 $20^{\circ}C$ 항온기에서 90일간 배양하여 자낭반 형성을 유도하였다. 자낭반은 자루가 가늘고 긴 컵 모양의 황갈색이었고 원통형의 수많은 자낭이 존재하였으며 자낭 안에서는 무색, 타원형이며 단세포로 된 8개의 자낭포자를 관찰할 수 있었다. 자낭포자의 크기는 $8.2{\sim}24.4{\times}3.6{\sim}7.2{\mu}m$ 정도였다. 병원성을 확인한 결과, 캠벨얼리와 거봉 품종 모두에서 병원성을 확인할 수 있었으며 상대적으로 캠벨얼리 품종이 감수성을 나타내었다. 이상과 같이 포도나무에 발생한 병징, 병원균의 균학적 특징 및 병원성 검정 결과, 병원균을 Sclerotinia sclerotiorum (Lib.) de Bary으로 동정하였으며, 이 병을 포도나무 균핵병으로 명명할 것을 제안한다.

• The Plant Pathology Journal
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• 제17권4호
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• pp.231-235
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• 2001

From April to May 1998, Phytophthora rot on pear, which has not been reported in Korea before, became an epidemic in the southeast part of the country under abnormally higher temperature and prolonged rainy days. Average temperature was about $3^{\circ}$ higher than in normal years, and 29 days were rainy during the 2 months in the areas surveyed. Over 1,000 orchards estimated at about 270 ha in 19 cultivation areas were infected by the disease, which occurred on all parts of the tree such as leaves, shoots, branches, stems, and flower clusters. Among 43 isolates collected from various locations and plant parts, 41 were identified as Phytophthora cactorum while 2 were identified as P. cambivora based on their mycological characteristics. The representative isolates revealed strong pathogenicity not only to pear but also to apple and peach. Among 23 pear cultivars tested, 7 were estimated as susceptible, 4 were moderate, and 11 were resistant to the pathogen. Results suggest that Phytophthora disease on pear is a potential threat to pear cultivation when environmental factors are favorable to disease development.

• Mycobiology
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• 제40권1호
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• pp.79-81
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• 2012

Cankers are localized dead areas in the bark of stems, branches or twigs of many types of trees and shrubs, and are usually caused by fungi. We observed severe canker symptoms in oak trees located in Gyeongnam province in 2011. A total 31 trees were discovered with cankers of varied size, with an average of $48.5{\times}15.2cm$. Black, half-rounded globular mound shaped stromata were associated with the cankers, and the asci of the fungi associated with the cankers were cylindrical shaped with their spore-bearing parts being up to 84 ${\mu}m$ in length. The average fungal ascospores size was $7.59{\times}4.23{\mu}m$. The internal transcribed spacer sequence for the canker causing fungus showed 99% similarity to the sequence of $Annulohypoxylon$ $truncatum$. In this study, the isolated fungus was precisely described and then compared with fungi of similar taxa.

• The Plant Pathology Journal
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• 제19권3호
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• pp.184-187
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• 2003

Verticillium wilt was first observed in 2001 on potatoes (Solanum tuberosum) cv. Superior at Daegwallyong area, one of the major seed potato producing areas in Korea. The wilted potato plants showed typical symptoms including gradual yellowing and interveinal necrosis. There was discoloration in the vascular tissues of the infected stems which turned light brown. Fungal isolates from discolored vascular tissues were whitish to creamy with folding on potato dextrose agar medium, where they used to produce resting dark mycelia but no micro-sclerotia. Conidiophores were septate with side branches, swelled at the base, and arranged in a whorl. Conidia were 2.5-11.2$\times$2.0-4.5 $\mu\textrm{m}$ um in size and were borne in small clusters at the tips of phialides. Optimal temperature range for mycelial growth was $25-30^{\circ}C$. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium albo-atrum Reink & Berth. Pathogenicity tests by root dipping method revealed that the fungus caused the same symptoms as observed in naturally infected potato plants. This is the first report of Verticillium wilt on potato caused by Verticillium albo-atrum in Korea.

• Mycobiology
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• 제43권2호
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• pp.170-173
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• 2015

Herein, we report the first occurrence of web blight of rosemary caused by Rhizoctonia solani AG-1-IB in Gangneung, Gangwon Province, Korea, in August 2014. The leaf tissues of infected rosemary plants were blighted and white mycelial growth was seen on the stems. The fungus was isolated from diseased leaf tissue and cultured on potato dextrose agar for identification. The young hyphae had acute angular branching near the distal septum of the multinucleate cells and mature hyphal branches formed at an approximately $90^{\circ}$ angle. This is morphologically identical to R. solani AG-1-IB, as per previous reports. rDNA-ITS sequences of the fungus were homologous to those of R. solani AG-1-IB isolates in the GenBank database with a similarity percentage of 99%, thereby confirming the identity of the causative agent of the disease. Pathogenicity of the fungus in rosemary plants was also confirmed by Koch's postulates.

• 한국산림과학회지
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• 제79권2호
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• pp.196-204
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• 1990

한국산(韓國産) 4개(個) 지역형(地域型) 소나무천연림(天然林)의 물질생산량(物質生産量) 및 물질생산구조(物質生産構造)를 파악하기 위하여 지역형별(地域型別) 전형적인 수형을 보이는 30~40년생(年生) 4개(個) 임분(林分)을 대상으로 현존량(現存量), 순생산량(純生産量), 생산능률(生産能率)을 조사비교한 결과 임분(林分) 전체의 현존량(現存量)은 안강형 29.87t/ha, 중남부평지형 110.89t/ha, 중남부고지형 133.53t/ha, 금강형 205.42t/ha으로써 큰 차이를 보였다. 부위별(部位別) 현존량(現存量) 구성비(構成比)는 안강형에서 금강형으로 갈수록 줄기의 목질부(木質部) 구성비(構成比)는 증가하는 반면(反面), 수피(樹皮), 생지(生枝), 잎, 뿌리의 구성비(構成比)는 감소하는 경향을 보였다. 임분(林分) 전체의 순생산량(純生産量)은 안강형 3.716t/ha/yr., 중남부평지형 10.796t/ha/yr., 중남부고지형 13.097t/ha/yr., 금강형 16.500 t/ha/yr.의 순으로 증가하였다. 부위별(部位別) 순생산량(純生産量) 구성비(構成比)는 안강형에서 금강형으로 감에 따라 줄기의 목질부(木質部), 생지(生枝)의 구성비(構成比)는 증가하는 반면, 잎의 구성비(構成比)는 감소하였다. 생지(生枝)의 경우 현존량(現存量) 구성비(構成比)와 상반(相反)된 경향을 보이는 것은 금강형으로 갈수록 자연락지율(自然落枝率)이 높기 때문인 것으로 추정(推定)되었다. 생산능률(生産能率)에 있어서 순동화율(純同化率)은 안간형, 중남부평지형, 중남부고지형, 금강형에서 각각(各各) 1.406, 1.920, 1.487, 1.677이었으며, 잎의 줄기 생산능률(生産能率)은 각각(各各) 0.239, 0.714, 0.572, 0.771이었다. 중남부평지형 조사시기(調査時期)의 차이를 고려할 때 순동화율(純同化率)과 줄기 생산능률(生産能率)은 안강형에서 금강형으로 감에 따라 증가하는 경향을 보이는 것으로 추정(推定)되었다.