• The Plant Pathology Journal
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• 제38권2호
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• pp.102-114
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• 2022

Pectobacterium carotovorum subsp. carotovorum (Pcc) is a gram-negative, broad host range bacterial pathogen which causes soft rot disease in potatoes as well as other vegetables worldwide. While Pectobacterium infection relies on the production of major cell wall degrading enzymes, other virulence factors and the mechanism of genetic adaptation of this pathogen is not yet clear. In the present study, we have performed an in-depth genome-wide characterization of Pcc strain ICMP5702 isolated from potato and compared it with other pathogenic bacteria from the Pectobacterium genus to identify key virulent determinants. The draft genome of Pcc ICMP5702 contains 4,774,457 bp with a G + C content of 51.90% and 4,520 open reading frames. Genome annotation revealed prominent genes encoding key virulence factors such as plant cell wall degrading enzymes, flagella-based motility, phage proteins, cell membrane structures, and secretion systems. Whereas, a majority of determinants were conserved among the Pectobacterium strains, few notable genes encoding AvrE-family type III secretion system effectors, pectate lyase and metalloprotease in addition to the CRISPR-Cas based adaptive immune system were uniquely represented. Overall, the information generated through this study will contribute to decipher the mechanism of infection and adaptive immunity in Pcc.

• 식물병연구
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• 제9권1호
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• pp.28-31
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• 2003

2002년 5월 상순 경상남도농업기술원 약초시험포장에 심겨진 꽃범의 꼬리에서 잎과 줄기가 수침상으로 물러지고, 그 부위에 흰색 곰팡이와 균핵이 생기면서 시들어 죽는 증상이 발생하였다. 여기서 병원균을 분리하였을 때 균핵은 PDA배지 상에서 잘 형성되었으며 모양은 구형, 타원형 또는 불규칙형으로 검은색이고 크기는 1.0~10.3$\times$1.0~8.4 mm이었다. 자낭반은 컵모양이며, 크기는 0.8~1.8 cm이었다. 자낭은 원통형이고 크기는 84~286$\times$4.7~26.3 $\mu\textrm{m}$이었다. 자낭포자는 타원형으로 단세포이며 무색이다. 크기는 7.6~12.8$\times$3.4~6.2 $\mu\textrm{m}$이었다. 균사생육 최적온도는 $25^{\circ}C$였다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과, Sclerotinia sclerotiorum으로 동정하였으며 이 병을 꽃범의 꼬리 균핵병으로 명명할 것을 제안한다.

• 식물병연구
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• 제29권2호
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• pp.204-204
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• 2023

• 식물병연구
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• 제13권1호
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• pp.57-60
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• 2007

2003년부터 2006년까지 4년 동안 경남농업기술원 과수포장과 진주시 농산물 도매시장에서 유통 판매중인 포도에서 이상증상이 발생하였다. 병징은 상처나 열과된 과실이 수침상으로 물러지면서 빠르게 부패되었다. 균총은 처음 흰색에서 연한 갈색으로 되며 검은색의 포자낭을 많이 형성한다. 균사생육 적온은 $25^{\circ}C$였다. 포자낭경은 처음 흰색에서 회색을 나타내며 크기는 $850{\sim}1,800{\mu}m$이며 폭은 $12{\sim}23{\mu}m$이었다. 포자낭은 처음에 흰색에서 검은색으로 되며 모양은 반구형으로 크기는 $80{\sim}190{\mu}m$이었다. 주축의 모양은 반구형으로 크기는 $70{\sim}95{\mu}m$이었다. 포자낭포자는 담갈색으로 단포이며 구형 또는 타원형으로 불규칙한 것이 많으며 크기는 $8{\sim}22{\times}6{\sim}10{\mu}m$이었다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과, 본 병해를 Rhizopus stolonifer (Ehrenberg ex. Fr.) Lind에 의한 포도 무름병으로 명명할 것을 제안한다.

• 식물병연구
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• 제14권1호
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• pp.57-60
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• 2008

2006년부터 2007년까지 2년 동안 진주시 농산물도매시장에 유통, 판매중인 사과(품종: 후지)에서 이상증상이 발생하였다. 병징은 상처나 열과된 과실이 수침상으로 물러지면서 빠르게 부패하였다. 균총은 처음 흰색에서 연한 갈색으로 되며 검은색의 포자낭을 많이 형성하며 균사생육 적온은 $25^{\circ}C$였다. 포자낭경은 처음 흰색에서 암갈색을 나타내며, 크기는 $950{\sim}1,900\;{\mu}m$이고 폭은 $12{\sim}22\;{\mu}m$이었다. 포자낭은 처음에 흰색에서 검은색으로 되며 모양은 구형 또는 반구형으로 크기는 $82{\sim}185\;{\mu}m$이었다. 주축의 모양은 반구형으로 크기는 $70{\sim}85\;{\mu}m$이었다. 포자낭포자는 담갈색으로 단포이며 구형 또는 타원형으로 크기는 $8{\sim}18{\times}7{\sim}8\;{\mu}m$이었다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과, 본 병해를 Rhizopus stolonifer(Ehrenb.) Vuill.에 의한 사과 무름병으로 명명할 것을 제안한다.

• The Plant Pathology Journal
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• 제25권1호
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• pp.91-94
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• 2009

An unreported disease of garlic was observed in commercial fields in Jiangsu province, China. The symptoms started as water soaked lesions at the base of the leaves. Later, water-soaked areas developed on stems and spread to the internal tissues, followed by yellowing and necrosis along leaf edges and soft rot of the stems. The causal organism isolated from symptomatic plants was identified as Pseudomonas fluorescens based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 168 rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto garlic plants. In addition, leek and shallot were susceptible to the P. fluorescens pathogen. However, the P. fluorescens pathogen failed to cause any symptoms when it was inoculated onto 15 other plants. This is the first report of a bacterial disease of garlic caused by P. fluorescens in China.

• The Plant Pathology Journal
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• 제25권4호
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• pp.429-432
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• 2009

An unreported disease of apricot was observed in orchards in Zhejiang province, China. Symptoms started as water soaked lesions on the fruit surface. Later, water-soaked areas developed and spread to the entire fruit, resulting in soft rot of the whole fruit. The causal organism isolated from symptomatic fruits was identified as Burkholderia cepacia based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 16S rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto fruits of apricot. In addition, European plum, Japanese plum, nectarine and kiwifruit were susceptible to the B. cepacia pathogen. However, the B. cepacia pathogen failed to cause any visible symptoms when it was inoculated onto 16 other fruits. This is the first report of a bacterial disease of apricot caused by B. cepacia in China.

• The Plant Pathology Journal
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• 제17권5호
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• pp.257-263
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• 2001

Species of the genus Orobanche are parasitic flowering plants, holoparasites, which cling to the roots of green plants. Their tiny seeds (200 x $250\mu\textrm{m}$) germinate in response to chemical stimuli produced by host and some non-host plants. Successful contact with their host leads to development of haustoria for obtaining water and food. The shoots above the ground expose flowers and disseminate seeds. Several samples of Orobanche ramosa, O. crenata, O. cernua, and O. egyptiaca were collected from different localities in Jordan. These samples showed one of the following disease symptoms: dry rot at the base of the stem; general deterioration and expanded lesion from base upward; soft tissue maceration of stem; and black rot of flower parts with incomplete maturation of the ovary and seeds. Isolation from diseased stems and seeds was made on three different mycological media. Several fungi were isolated, mainly, Fusarium spp., Alternaria alternata, Rhizoctonia sp., Dendrophora sp., Chaetomium sp., and an ascomycetus fungus with a perithecium. Pathogenicity tests showed that Fusarium spp. and Alternaria alternata attacked healthy living tissue of Orobanche spikes. These fungi caused lesions of black soft rot and complete deterioration within 5-7 days. They also attacked Orobanche seeds, arresting their germination and causing maceration of non-germinated and germinated seeds after 5-7 days of incubation. Meanwhile, Dendrophora sp. and Chaetomium sp. caused limited lesion at first, but were able to colonize the tissue as it aged and senesced. This study showed the presence of a potential endogenous pathogenic fungi in Jordan, which can be investigated as a biological control for Orobanche.

• Mycobiology
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• 제46권2호
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• pp.92-100
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• 2018

The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.

• 생물환경조절학회지
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• 제4권2호
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• pp.240-245
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• 1995

온도 및 광량이 고추냉이의 지상부 및 지하부 생장과 주요 병해발생에 미치는 영향을 조사하기 위하여 생장상의 온도를 10, 17 및 23$^{\circ}C$ 처리구로 하고 차광처리조건을 25, 50 및 75%로 조절하여 실험을 수행하였던 바 그 결과를 요약하면 다음과 같다. 유묘 정식 180일후 조사결과 초장은 생육온도에 따라 차이가 현저히 인정되었으나 17$^{\circ}C$구에서 가장 좋은 결과를 보였으며, 엽병의길이와 직경은 17$^{\circ}C$구를 정점으로 이보다 온도가 높거나 낮음에 따라 감소되는 경향을 보였다. 지하경에 있어서 직경은 1$0^{\circ}C$, 23$^{\circ}C$구간에서는 유의차가 인정되지 않았으며, 17$^{\circ}C$구에서 가장 양호하였다. 길이는 각 처리구별로 유의차가 인정되었으며 역시 17$^{\circ}C$구에서 가장 길었다. 차광처리 75%구가 50, 25%구에 비하여 지하경의 크기는 유의성이 인정되었으나 50%와 25%구의 처리간에는 유의성이 인정되지 않았다. 지하경의 직경과 무게에 있어서 75%구가 기타 처리구에 비하여 양호하였으며 전체 생체중은 75%, 50% 및 25%처리구간에서는 유의차가 인정되었다. 연부병과 묵입병의 발병률은 온도가 증가할수록 증가되었으나 차광량이 많을수록 연부병과 묵입병의 발병율은 감소하는 경향이었다.