• The Plant Pathology Journal
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• 제17권4호
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• pp.194-200
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• 2001

Chrysanthemum stunt viroid (CSVd) ws identified in chrysanthemum cv. Chunkwang showing symptoms of stunt with leaf distortion (K1) and stunt with chlorosis of leaves (K2) collected from the main cultivation area of Masan, Kyongnam province in Korea. The specific RNAs related with the diseased chrysanthemums were detected. Full-length 354 bp CSVd cDNAs were amplified from infected tissue by reverse transcription and polymerase chain reaction using a pair of primers specific for CSVd sequence. The amplified cDNA products were analyzed by agarose gel electrophoresis and the specific cDNAs were cloned. Nucleotide sequences of the two CSVd isolates K1 and K2 varied. Phylogenetic analysis of the nucleotide sequences of CSVd isolates indicated that K1 was closely related with J2 and Am 2 isolates. K1 and K2 were transmitted by grafting to Dendranthema grandiflorum cv. Mistletoe, Gynura aurantiaca, and Lycopersicon esculentum cv. Rutgers. This is the first report of CSVd in D. grandiflorum in Korea.

• 한국식물병리학회지
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• 제13권2호
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• pp.132-137
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• 1997

Phytotoxicity of the culture filtrate and culture conditions for the production of the phytotoxin by Exserohilum monoceras 92-044 were examined. The necrotic lesions were developed on the leaves of Echinochloa crus-galli within 48 hrs after inoculation of the culture filtrate, and the leaves were completely blighted within 5∼7 days. Maximum toxicity was found in the culture broth containing 20% V-8 juice. Phytotoxin accumulation and fungal growth reached their highest peak at around 11 days. Typical symptom appeared on the leaf of E. crus-galli within 48 hrs. Only a weak chlorosis appeared on rice, Arundinella hirta (THUNB) and henry crabgrass (Digitaria sanguinalis SCOP.), but no further symptom developed.

• 미생물학회지
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• 제13권1호
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• pp.31-36
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• 1975

Chlorella ellipsoidea cells were cultured in a phosphate, magnesium, sulfur or potassium-free medium. Some portions of cells were taken out at intervals during the culture, and physiological activities such as growth rate, reproduction, photosynthetic activity, and biosynthesis of cholorophyll of macro-element deficient cells were measured. 1) Generally, growth rate, reproduction, photosynthetic activities, and biosynthesis of chlorophyll of the macro-element deficient cells decreased more or less, compared with those of the normal cells. 2) The growth and reproduction of the algal cells in sulfur, or magnesium free medium were retarted severely with the chlorosis ; the photosynthetic activity and the content of chlorophyll showed the same tendency. 3) It is considered that the decrease in growth rate of macro-element deficient Chlorella cells is due to the decrease in photosynthetic activity owing to the decrease in chlorophyll content of the cells.

• The Plant Pathology Journal
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• 제21권4호
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• pp.377-382
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• 2005

Infection rate of Chrysanthemum stunt viroid (CSVd) in 64 commercial chrysanthemum cultivars cultivated in Korea ranged from 9.7 to 66.8$\%$. Symptoms on leaves of CSVd-infected chrysanthemum included yellow spots, chlorosis, vein clearing, vein bending and crumpling. CSVd induced flower malformation in 'Scot', color change in 'Sharotte', and color breaking in 'Sharon'. CSVd caused reduction of plant height, leaf size, flower size and the flowers number by $32-50\%,\;26-35\%$, $14-36\%\;and\;14-75\%$, respectively. In conclusion, CSVd affected plant height, leaf size and flower quality in chrysanthemum plants.

• The Plant Pathology Journal
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• 제36권3호
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• pp.297-302
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• 2020

Root-knot nematodes (Meloidogyne spp.) are the most destructive group of plant-parasitic nematodes. Plants infected by Meloidogyne spp. develop above-ground symptoms, stunting, yellowing, nutrient deficiencies, and gall formations with typical hook-shaped root tips. Infected plants experience yield losses. During 2018-2019 survey, leaf chlorosis rice plants were found in 206 fields of 67 counties in Guangxi, China, around 30 days after transplanting. Galls and hooked tips on the roots and pear-shaped females were observed. About 32.04% of fields were infested with the nematode. The nematodes were identified as Meloidogyne graminicola base on morphological and molecular analysis. To the best of our knowledge, this is the first report of M. graminicola on rice plants in Guangxi, China. The results of this study urge the discovery of resistant cultivars and the development of management strategies.

• 한국식물병리학회지
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• 제14권2호
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• pp.188-190
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• 1998

Fusarium wilt of lisianthus occurred severely throughout all cultivation areas, especially in alpoine areas during summer season and the disease incidence was 5 to 30 percent in Korea. The major symptoms of the disease were wilt with chlorosis and water deficiency, stunted plants and scorched leaves. Severe symptoms appeared just after high temperature period around late August in Daekwallyong area. Whit and pale red colored mycelia were developed on stems of infected plants near the soil surface. The causal organism of Fusarium wilt of lisianthus was isolated and identified as Fusarium oxysporum f. sp. eustomae on the basis of pathogenic and cultural characteristics. The causal organism was reisolated from all infected and inoculated stems of plants. This is the first report referring to F. oxysporum f. sp. eustomae of lisianthus in Korea.

• 한국균학회지
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• 제49권3호
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• pp.399-403
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• 2021

Stem blight symptoms were observed in greenhouse-grown bottle gourds (Lagenaria siceraria) in Wanju, Korea. Infected plants showed leaf chlorosis and wilting; the plants eventually died with the infected leaves remaining attached, and black sclerotia formed on the diseased stem. Based on the morphological characteristics and pathogenicity results and sequence analyses of the internal transcribed spacer, translation elongation factor 1-α, β-tubulin, and calmodulin regions, the isolated fungus was Macrophomina phaseolina. This is the first report of charcoal rot in Lagenaria siceraria caused by Macrophomina phaseolina in Korea.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.148.1-148
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• 2003

Natural virus infection of cultivated Daphe odora plants showing chlorosis and stunting was observed and their causal agent was investigated. An isolate of isometic virus was purified from infected leaf tissues, and it could infect systemic severe mosaic on Chenopodium quinoa and C. amaranticolor. cDNA library was generated from partially purified viral RNAs and oligo dT primer-pSPORTl system, and recombinant clones were selected and their inserts were sequenced randomly. Nucleotide sequences of the virus were analyzed by BLAST, and it was closely related to members of subgroup B in the genus Nepovirus. The sequence analysis suggest that the virus was identified as an isolate of Cycas necrotic stunt virus (CNSV) because it was 89.7 ％ and 94.7 ％ identical to known CNSV for the CP and 3' noncoding region, respecitively. RT-PCR was performed to screen disease incidence of CNSV in Daphe plants, and five out of 10 plants (50 ％) were infected by CNSV This is the first sequence information of CNSV from Daphe plants.

• 환경생물
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• 제32권4호
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• pp.297-305
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• 2014

부산시 강서구 낙동강 하구에서 채집한 방사무늬김(Porphyra yezoensis Ueda)의 용존산소 생산율은 $68.8{\pm}46.0{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, 질산염과 인산염 흡수율은 각각 $2.5{\pm}1.8{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, $0.18{\pm}0.11{\mu}mol\;{g_{FW}}^{-1}h^{-1}$ 그리고 용존무기탄소 흡수율은 $87.1{\pm}57.3{\mu}mol\;{g_{FW}}^{-1}h^{-1}$이었다. 용존산소 생산율과 질산염, 인산염, 용존무기탄소 흡수율은 각각 음의 선형관계를 보여, 광합성활동에 의한 결과물임을 파악할 수 있었다. 김의 생중량에 따른 이들 성분의 생산/흡수율은 로그함수적으로 감소하여, 성체(>~0.3 g)보다는 어린 엽체의 광합성효율이 매우 높은 것으로 나타났으며, 이는 질소부족으로 인한 황백화가 양식초기에도 발생할 수 있음을 제시하였다. 우리나라 시도 단위로 월별 생산되는 김 생산량과 양식면적을 바탕으로 질소요구량과 탄소흡수율을 산정한 결과, 생산량이 가장 높은 전라남도보다 부산(경상남도 포함)과 전라북도의 단위면적당 질소요구량이 높았다. 최근 김 황백화가 빈발하는 전라북도는 좁은 면적에서의 과밀 생산과 최대수확기가 육상과 저층으로부터 영양염 공급이 부족한 12~1월인 점 등이 황백화의 원인인 것으로 추정된다.

• 한국초지조사료학회지
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• 제24권2호
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• pp.105-114
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• 2004

Orcharduass 및 white clover에서 미량요소 Fe, Mn, Cu, Zn의 systematic variations 시비가 목초의 생육, 재화, 수량, 양분 함량 등에 미치는 영향 등을 구명하였다. 다량요소 양분을 동일량 시비한 조건에서 시험군-1(Fe/Cu), 시험군-2(Mn/Zn), 시험군-3(Fe+Cu/Mn+Zn)의 처리내용은 시험군별 총 시비량을 systematic variation 방법으로 각각 0/100, 25/75, 50/50, 75/25, 100/0% 비율로 나누어 시비 처리 하였고, 시험군-4(FeMn/Cu/Zn)에서는 각 기준처리 70％， 기타처리는 각각 10％(합계 100％) 비율로 시비 처리하였다. 1) White clover에서 Fe과 Mn 간의 길항작용에 의한 Mn과 Fe결핍 황화현상을 블 수 있었다. 또한 처리별 뿌리생육, 근류와 개화에 미치는 영향은 일반적으로 상호 밀접한 연관성을 보였다. Fe/Cu 비율시험에서 white clover는 0/100 및 25/75％ 처리에서 F-결핍 황화현상이 나타났으며 100/0%처리는 다른 처리에 비해서 뿌리생육(색도, 밀도 및 근류형성) 및 재화/화아 수가 불량하였다. 그러고 50/50과 75/25% 처리에서는 다른 처리에 비해서 다소 빠른 개화를 보였다. 2) Mn/Zn 비율시험에서 white clover는 특히 0/100％ 처리에서 심한 Mn 결핍 황화현상이 나타났으며 또한 25/75 및 50/50 처리에서도 이 증상을 다소 불 수 있었다. 높은 Mn/Zn 비율의 처리에서 일반적으로 양호한 부리생육과 증가된 개화/화아 수를 보였다. 3) Fe+Cu/Mn+Zn 비율시험에서 white clover는 0/100% 처리에서 Fe 결핍 황화현상을 그리고 100/0 처리에서는 Mn 결핍 황화현상을 보였고 모두 뿌리생육의 불량과 개화/화아 수 감소를 보였다. 75/25 비율에서 가장 양호한 뿌리생육과 많은 개화/화아 수를 보였다. 4) Fe/Mn/Cu/Zn 비율시험에서 white clover는 처리비율에 따라서 Fe과 Mn 결핍증상이 나타났으며 반면에 Cu와 Zn 결핍증상은 나타나지 않았다. Zn>Cu>Mn>Fe-7％ 시비처리 순으로 개화/화아 수가 많았다.