• 식물병연구
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• 제8권2호
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• pp.113-116
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• 2002

A sclerotinia rot of Leonurus sibiricus caused by Sclerotinia sclerotio겨m occurred severely in farmer's fields at Seosang-myon, Hamyang-gun, Gyeongnam Province, Korea in 2001. The typical symptoms of the disease were that leaves, stems or collar of the infected plants at first became darker green and then watery soft rotted, and white fluffy mycelia formed on the lesion developed into black sclerotia later, Sclerotia on the plant and PDA medium were globose to cylindrical or irregular in shape, and 0.8~10.3$\times$0.8~6.4 m in size. Aphothecia with numerous asci were cup-shape, and 0.6~1.2 cm in diameter, Asci with 8 spores were cylindrical, and 87~246$\times$4.6~21.6 $\mu\textrm{m}$ in size. Ascospores of one cell were hyaline, ellipsoid to ovoid in shape, and 10.2~14.6$\times$4.7~7.2 $\mu\textrm{m}$ in size. The range of temperature for mycelial growth was from 5 to 3$0^{\circ}C$, and the optimum was $25^{\circ}C$. This is the first report on the sclerotinia rot of L. sibiricus caused by Sclerotinia sclerotioum in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.93-106
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• 2003

Soilborne diseases pose a serious problem for mulberry cultivation during nursery plantation and established gardens, which cause severe loss in revenue generation of mulberry growers as compared to foliar diseases. Various soilborne diseases affect mulberry. Among them, root knot and root rot affect the established plantation resulting in severe loss in leaf yield apart from deterioration in leaf quality, which is a pre-requisite in successful sericulture to get the good quality of cocoons. Besides, stem-canker, cutting rot, collar rot and die-back, affect the initial establishment and survivability of mulberry plantation in nursery. The problem is difficult to handle, due to the complex nature of the diseases and also involvement of various biotic and abiotic factors. This is compounded by the occurrence of disease complex (especially nematode ＋ soilborne pathogenic microbes) in established mulberry gardens, which facilitates quick spread of the disease and enhance the plant mortality, resulting substantial loss in leaf yield. Therefore, prevention and timely control measures need to be taken up to protect the mulberry plants from different soilborne plant pathogens. In this review article, symptomatology, epidemiology, disease cycle and control measures of soilborne diseases of mulberry are discussed.

• 한국식물병리학회지
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• 제14권2호
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• pp.115-119
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• 1998

Root rot of carnation caused by isolates of Phytophthora was found at Kongju, 1996. Infected plants appeared symptoms of wilting, brown discoloration on collar area and consequently led to death. The causal pathogen was identified as Phytophthora nicotianae based on morphological, cultural and physiological characteristics. Mycelium was grown to rosette colony pattern on corn meal agar and the growth was 10.2 mm/day on 10% clarified V8 medium at $25^{\circ}C$. Swelling with radiating hyphae was formed in water and on agar within 7 days. Chlamydospores were abundantly produced on agar within 7 days. Sporangium was prominent papillate, 2~3 apex, 1.2 : 1 l/b ratio, lateral attacment on sporangiospore and was rarely produced on solid media but produced in water. The shape of sporangium was spherical or ovoid, and the size was 34~73$\times$32~60 (av. 33$\times$66.5) ${\mu}{\textrm}{m}$ in dimension. The isolates were heterothallic, and mating type A2. Oogonium was spherical, ovoid, 26~36 (av. 36 ${\mu}{\textrm}{m}$) in diameter, and antheridium was amphygynious to oogonia. The fungus was able to grow 10~35$^{\circ}C$, and optimal temperature was 27$^{\circ}C$.

• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.173-174
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• 2020

• 식물병연구
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• 제10권1호
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• pp.21-24
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• 2004

2002년 경남 하동군 진교면 노지재배 포장과 2003년 진주시 문산읍 촉성재배 비닐하우스 고추에서 이상증상이 발생하였다 병징은 지제부의 줄기가 수침상으로 물러지고 부패하면서 암갈색으로 변하고 시들면서 말라 죽는다. 병반부에 흰색의 곰팡이가 솜털처럼 생기고, 병반 부위와 토양 표면에 갈색의 둥근 균핵이 많이 형성된다 병원균의 균사생장 및 균핵형성은 감자한천배지에 배양시 3$0^{\circ}C$에서 가장 양호하였다. 균핵은 갈색 또는 암갈색으로 크기는 1.0∼2.7 mm이었다. 균사 특유의 clamp connection이 관찰되었고 균사 폭은 3.6∼10.2 $\mu\textrm{m}$이었다. 본 병원균을 Sclerotium rolfsii로 동정하였으며 고추 흰비단병으로 명명할 것을 제안한다.

• 식물병연구
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• 제10권3호
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• pp.159-166
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• 2004

잇꽃에 발생하는 식물병들은 탄저병(Colletotricum acutatum), 잿빛곰팡이병(Botrytis cinerea), 흰가루병(Sphaerotheca fuliginea), 흰비단병 (Sclerotium rolfsii), 역병 (Phytophthora cactorum), 뿌리썩음병 (Fusarium oxysporum), 잎점무의병 (Alternaria carthami, A. alternata), 모잘록병(Pythium ultimum), 녹병(Puccinia carthami), 바이러스(CMV) 등 10종이었다. 잇꽃 병의 발생소장 및 피해실태 조사에서 탄저병은 전 생육기에 걸쳐서 뿌리, 잎, 줄기, 화두 등 모든 부위에 발생하였다. 노지재배시 평균 발병주율이 60% 이상으로 가장 큰 피해를 주는 병해였으며, 비가림 하우스에서는 5% 내외의 발병율을 나타내었다. 잿빛곰팡이병은 비가림 하우스 내에서 개화기인 6월 중순부터 수확기까지 80% 이상의 발병주율과 30% 내외의 발병화두율을 나타내었다. 모잘록병이 파종 후 30일경까지 5∼10%정도 발생하였으며, 기타병해로 시들음병, 흰비단병, 역병, 흰가루병, 녹병, 잎점무의병 등은 1% 내외의 발병율을 보여 피해가 경미하였다. 잇꽃 모잘록병에 대한 약제 방제효과는 다찌가렌 액제 침지처리와 토로스 수화제 분의처리 효과가 우수하였다. 잇꽃 탄저병에 대한 약제방제 효과는 메티람수화제와 이미녹타딘트리스알베실레이트$.$치람 수화제 방제가가 85%이상으로 우수하였다. 잿빛곰팡이병의 약제방제시험에서는 비가림 하우스내에서 이프로 수화제, 후루아지남 수화제, 포리옥신 수화제를 처리하였으나 방제가는 80%미만이었으며, 노지재배시 이미녹타딘트리스$.$치람 수화제의 방제가는 91.1%였고, 후루아지남 수화제의 방제효과는 89.6%였고 이프로 수화제의 방제가는 89.2%였다.

• 식물병과 농업
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• 제5권2호
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• pp.77-83
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• 1999

In 1997 surveys 82 out of 180 crucifer fields were infected with clubroot disease in a range of 1-100% of diseased plants and among crucifier crops Chinese cabbage was the most severe, In cropping systems Chinese cabbage-monocropping of Chinese cabbage-radish were found to be most common in major Chinese cabbage production areas. Welsh onion squash or paddy rice were also planted between cropping of Chinese cabbage. Paddy fields converted to upland were lowered in incidence of clubroot disease and fields with loam to silty loam soil were more severe in disease than those with sandy soil. Soil pH and organic contents were nor related to clubroot disease severity. Soil fauua such as total fungi bacteria actinomyces Pseudomonads and Bascillus were not correlated with severity of the disease. Root rall development on Chinese cabbage seedlings was initifially observed under a microscope 13 days after inoculation with Plasmodiophora brassicae but 18 days by naked eyes after inoculation. Root galls were formed mostly around collar roots and gradually spread to main root lateral roots and secondary root branches. Root galls started to enlarge greatly in size and weight from 23 days after inoculation. Chinese cabbage plants at mid-growth stage with root gall development were reduced to 1/2 of that of healthy plants in number of leaves 1/4-1/5 in above ground fresh weight 1/6 in root length but increased to 3 times in diameter of collar root. Diseased plants had little root hairs. Diseased Chinese cabbage plants at harvest were reduced by 9,1-11.8% in head weight compared to healthy plants a positive correlation was observed between root and head weight but those relationships were rot found in the diseased plants.

• 한국균학회지
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• 제46권3호
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• pp.345-351
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• 2018

A fungal isolate denoted NC14-264 was isolated from the soil in Jeongeup, Jeollabuk-do, Korea. Species in genus Plectosphaerella are pathogenic to several plant species, leading to fruit, root, and collar rot and collapse. In this study, a strain NC14-264 belonging to the Plectosphaerella was isolated from the soil and identified. Colonies were moderately grown, reaching 54 mm in diameter on potato dextrose agar, 49 mm on malt extract agar, and 55 mm on oatmeal agar at $25^{\circ}C$ after 10 days of incubation. Most Plectosphaerella species are distinguishable morphologically by irregular chlamydospores and different proportions of phialides and conidia. Based on morphological features and phylogenetic analysis using the internal transcribed spacer region and partial 28S rRNA gene sequences, the isolated fungus was identified as Plectosphaerella sinensis belonging to the Plectosphaerellaceae. This is the first report of P. sinensis in Korea.