• The Plant Pathology Journal
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• 제34권6호
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• pp.480-489
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• 2018

Bitter rot caused by Colletotrichum species is a common fruit rotting disease of apple and one of the economically important disease in worldwide. In 2015 and 2016, distinct symptoms of bitter rot disease were observed in apple orchards in five regions of South Korea. In the present study, infected apples from these regions were utilized to obtain eighteen isolates of Colletotrichum spp. These isolates were identified and characterized according to their morphological characteristics and nucleotide sequence data of internal transcribed spacer regions and glyceraldehyde-3-phosphate-dehydrogenase. Molecular analyses suggested that the isolates of Colletotrichum causing the bitter rot disease in South Korea belong to 4 species: C. siamense; C. fructicola; C. fioriniae and C. nymphaeae. C. siamense and C. fructicola belonged to Musae Clade of C. gloeosporioides complex species while C. fioriniae and C. nymphaeae belonged to the Clade 3 and Clade 2 of C. acutatum complex species, respectively. Additionally, we also found that the isolates of C. gloeosporioides species-complex were more aggressive than those in the C. acutatum species complex via pathogenicity tests. Taken together, our results suggest that accurate identification of Colletotrichum spp. within each species complex is required for management of bitter rot disease on apple fruit in South Korea.

• 식물병연구
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• 제6권1호
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• pp.1-5
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• 2000

• 원예과학기술지
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• 제29권2호
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• pp.151-155
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• 2011

Botrytis cinerea에 의한 딸기 잿빛곰팡이병은 최대 50%까지 발생하여 큰 피해를 주는 딸기의 주요 병해이다. 약제살포시기는 잿빛곰팡이병의 성공적인 방제를 좌우하는 필수적 요소이다. 딸기 '설향' 품종에 대한 잿빛곰팡이병 방제효과 검정을 위해 fenhexamid + imonoctadine tris, cyprodinil + fludioxonil, Bacillus subtilis QST713을 ex vivo에서 개화전, 개화기, 미착색과, 성숙과 단계부터 처리하여 효과를 비교하였다. 또한 '설향' 품종을 공시하여 ex vivo와 재배포장에서 cyprodinil + fludioxonil 혹은 fludioxonil을 저온($0^{\circ}C$, 5시간) 전후 처리하여 잿빛곰팡이병 방제효과를 조사하였다. 딸기 꽃과 성숙과실은 미착색과실보다 B. cinerea에 더 감수성이었다. ex vivo에서 개화단계별 약제방제효과는 fenhexamid + iminoctadine tris는 개화직전과 개화기, cyprodinil + fludioxonil은 개화기에 효과적이었으나 Bacillus subtilis QST713은 처리간 유의성이 없었다. 2010년 딸기 잿빛곰팡이병 방제효과는 fludioxonil을 개화기에 1주일 간격으로 2회 처리시 효과적이었다. 딸기 'Redpearl'과 '설향' 품종은 '매향'과 'Akihime' 품종보다 저온에 더 감수성이어서 주의를 요했으며 cyprodinil + fludioxonil을 저온처리 전에 살포시 90%이상의 방제효과를 나타냈다. 2010년 재배포장에서 잿빛곰팡이병 방제효과는 저온 발생 전 혹은 저온 발생 후 1주일 간격 2-3회 fludioxonil처리가 효과적이었다. 이런 결과로 딸기 잿빛곰팡이병 방제를 위한 약제의 효과적인 처리시기는 개화와 저온이 밀접한 관련이 있음을 알 수 있었다.

• Mycobiology
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• 제33권3호
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• pp.163-165
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• 2005

In April 2002 and 2003, soft rot on fruit of eggplant (Solanum melongena) caused by Choanephora cucurbitarum was observed in the experimental fields at Gyeongnam Agricultural Research and Extension Services in Korea. The disease began with water-soaking and dark-green lesions, and then the infected tissues were rapidly rotten. Sporangium was subglobose in shape and sized $40{\sim}130\;{\mu}m$. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and measured as $12{\sim}20\;{\times}\;6{\sim}14\;{\mu}m$. Sporangiospores having three or more appendages were elliptic, fusiform or ovoid in shape, dark brown or brown in color, and sized $14{\sim}20\;{\times}7{\sim}16\;{\mu}m$. The fungus grew well on potato dextrose agar between 15 and $40^{\circ}C$ and its optimum growth temperature was $30^{\circ}C$. Based on morphological characteristics, the causal fungus of the fruit soft rot of eggplant was identified as C. cucurbitarum. This is the first report on the soft rot of S. melongena caused by C. cucurbitarum in Korea.

• The Plant Pathology Journal
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• 제19권5호
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• pp.227-230
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• 2003

Ripe rot was commonly found in overripe kiwifruits (Actinidia deliciosa) during a disease survey conducted in Jeju and Jeonnam provinces in Korea in 1999. While the disease did not manifest any clear external symptoms on kiwifruits, it caused portion of the fruit surface to collapse. Watersoaked flesh tissue could be seen on the sunken part when the skin of the collapsed portion was peeled off. The milky internal symptom with dark green margin developed concentrically as the fruit ripened. A species of Botryosphaeria was consistently isolated from lesions showing typical symptoms of ripe rot on kiwifruit, and its pathogenicity was confirmed by artificial inoculation test on healthy kiwifruits. The fungus was also pathogenic to apple and pear. The mycological characteristics of the fungus were consistent with those of Botryosphaeria dothidea. This is the first report on the detailed mycological characteristics of the causal organism of post-harvest ripe rot of kiwifruit in Korea.

• The Plant Pathology Journal
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• 제35권5호
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• pp.530-537
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• 2019

Fuji, a major apple cultivar in Korea, is susceptible to white rot. Apple white rot disease appears on the stem and fruit; the development of which deteriorates fruit quality, resulting in decreases in farmers' income. Thus, it is necessary to characterize molecular markers related to apple white rot resistance. In this study, we screened for differentially expressed genes between uninfected apple fruits and those infected with Botryosphaeria dothidea, the fungal pathogen that causes white rot. Antimicrobial tests suggest that a gene expression involved in the synthesis of the substance inhibiting the growth of B. dothidea in apples was induced by pathogen infection. We identified seven transcripts induced by the infection. The seven transcripts were homologous to genes encoding a flavonoid glucosyltransferase, a metallothionein-like protein, a senescence-induced protein, a chitinase, a wound-induced protein, and proteins of unknown function. These genes have functions related to responses to environmental stresses, including pathogen infections. Our results can be useful for the development of molecular markers for early detection of the disease or for use in breeding white rotresistant cultivars.

• The Plant Pathology Journal
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• 제37권4호
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• pp.347-355
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• 2021

Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In order to control ripe rot on Actinidia chinensis cultivar 'Zesy002', several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadinetris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothidea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the untreated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.

• 생물환경조절학회지
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• 제18권4호
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• pp.420-424
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• 2009

고랭지 착색단고추 여름재배시 착과 증대 및 품질향상을 위하여 호박벌을 이용한 수정증대 효과에 대하여 검토하였다. 호박벌에 의하여 처리기간 동안 착과수의 증가는 있었으나 재배기간의 총 수량에서는 무처리와 비교하여 차이가 없었다. 과실의 종자수는 무처리에 비해 호박벌 처리에서 7.3%가 증가되었으나 배꼽썩음과 발생은 높았다. 과중의 분포 비율이 호박벌 처리에 의하여 SS 사이즈는 감소하고 L 사이즈가 증가하여 수출 규격품율이 향상되었다. 따라서 고랭지 여름재배시 착과증진을 위한 호박벌 처리는 착과율을 높이고 과실의 종자수를 증가시켜 수출 규격품율을 높이는 등 고품질 생산에 효과적이었으며 배꼽썩음과 방지에 대한 검토가 추후 필요할 것으로 판단되었다.

• 한국균학회지
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• 제30권2호
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• pp.166-169
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• 2002

2002년 진주시 농산물 도매시장에서 Rhizopus stolonifer에 의한 감귤 무름병이 발생하였다. 병징은 처음 과일 껍질 부분이 수침상으로 물러지면서 급속히 진전되어 썩었다. 균사는 처음 흰색에서 연한 갈색으로 되며 검은색의 포자낭을 형성한다. 포자낭병은 처음 무색에서 회색을 나타내며 포자낭을 끝에 만들고 길이는 $900{\sim}4300{\mu}m$였다. 포자낭은 처음에 무색에서 나중에 검은색이고 아구형으로 크기는 $98{\sim}346{\mu}m$이다. 추축은 아구형 또는 타원형으로 직경은 $60{\sim}216{\times}72{\sim}143{\mu}m$이다. 포자낭포자는 담갈색으로 단포이며 구형 또는 타원형으로 크기는 $8{\sim}18.3{\mu}m$였다. 균사생육 적온은 $25^{\circ}C$였다. 이상과 같이 병원균의 균학적 특징과 병원성을 검정한 결과 이병을 R. stolonifer에 의한 감귤 무름병으로 명명할 것을 제안하고자 한다.

• The Plant Pathology Journal
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• 제26권3호
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• pp.223-230
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• 2010

The Burkholderia cepacia complex isolates causing bacterial fruit rot of apricot were characterized by speciesspecific PCR tests, recA-HaeIII restriction fragment length polymorphism (RFLP) assays, rep-PCR genomic fingerprinting, recA gene sequencing, and multilocus sequence typing (MLST) analysis. Results indicated that the isolates Bca 0901 and Bca 0902 gave positive amplifications with primers specific for B. vietnamiensis while the two bacterial isolates showed different recA-RFLP and rep-PCR profiles from those of B. vietnamiensis strains. In addition, the two bacterial isolates had a higher proteolytic activity compared with that of the non-pathogenic B. vietnamiensis strains while no cblA and esmR marker genes were detected for the two bacterial isolates and B. vietnamiensis strains. The two bacterial isolates were identified as Burkholderia seminalis based on recA gene sequence analysis and MLST analysis. Overall, this is the first characterization of B. seminalis that cause bacterial fruit rot of apricot.