• The Plant Pathology Journal
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• 제15권5호
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• pp.302-307
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• 1999

Occurrence of soft rots was observed on Dendrobium phalaenopsis and Phalaenopsis sp. that were grown at the greenhouses in Sunchon and Kwangyang areas, Chonnam province of Korea in 1997 and 1998. Typical soft rot symptom appeared frequently on young plants of D. phalaenopsis and Phalaenopsis sp. Soft rot symptom usually appeared on old leaves of D. phalaenopsis, and extended into whole leaves, accompanying blighting of whole plants. Symptom began as a small water-soaked lesion on old leaves of Phalaenopsis sp., which enlarged rapidly on the leaves and eventually resulted in soft rots of whole plants. The causal organism isolated from the infected lesions was identified as Erwinia chrysanthemi based on its pathogenicity, physiological and biochemical characteristics, and the results of the BIOLOGTM program. The bacterial soft rot caused by e. chrysanthemi was firstly describe din D. phalaenopsis and Phalanopsis sp. in Korea.

• 식물병연구
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• 제24권4호
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• pp.339-341
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• 2018

Amaranth has the potential for good materials related to nutrients and health benefits. There are several diseases of amaranth such as leaf blight, damping-off, and root rot. As a causal agent of soft rot disease, Pectobacterium spp. could infect various plant species. In this study, we isolated the bacterial pathogen causing soft rot of amaranth in South Korea. In Gangneung, Gangwon province during 2017, amaranth plants showed typical soft rot symptoms such as wilting, defoliation and odd smell. To isolate pathogen, the macerated tissues of contaminated amaranth were spread onto LB agar plates and purified by a single colony subculture. One ml bacterial suspension of a representative isolate was injected to the stem of five seedlings of 2-week-old amaranth with a needle. Ten mM magnesium sulfate solution was used as a negative control. 16S rDNA gene and recA gene were sequenced and compared with the reference sequences using the BLAST. In the phylogenetic tree based on 16S rDNA gene and recA gene, GSA1 strain was grouped in Pcb.

• 한국식물병리학회지
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• 제3권3호
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• pp.236-238
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• 1987

A bacterial disease of elephant foot, Hydrosome rivieri Engl., was newly found in Taejon, Korea in August 1986. The affected plants showed symptoms of soft rot on leaf blades and petioles. Bacterial isolates from affected plants found to be pathogenic to elephant foots by antificial inoculation, producing similar symptoms with those produced naturally. The baterium was also pathogenic to carrot, Chinese cabbage, radish, potato and onion, and developed symptom of soft root on them. On the basis of bacteriological characteristics and pathogenicity, tested bacterium was identified as Erwinia carotovora subsp. carotovora and this disease was proposed to name 'Bacterial soft rot of elephant foot'.

• 한국식물병리학회지
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• 제14권6호
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• pp.738-740
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• 1998

Bacterial soft rot was occurred on fruit of pepper that was grown in Chunceon, Kangwon province, Korea. The symptoms began as a small hole at 5 mm diameter, which made injury by a tobacco bud worm (Heliothis assulta). The affected fruit became soft and produced offensive odor. The causal organism was isolated from the diseased fruit and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and biochemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on pepper in Korea.

• 한국식물병리학회지
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• 제14권5호
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• pp.484-490
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• 1998

Microorganisms associated with seed-rhizome rot of gingers preserved in three underground storage caves were identified with respect to rot types. Rot patterns were grouped into 4 different types : yellow soft rot, brown rot, localized ring rot, and water-soaked rot. Water-soaked rot was highest in frequency with 40% and ring rot the least with 14%. Causal pathogens differed with rot type, yellow soft rot by Erwinia carotovora and Pseudomonas aeruginosa, brown rot by Fusarium solani and Pseudomonas aeruginosa, localized ring rot by F. solani, and water-soaked rot by Pythium spinosum and P. ultimum. Pythium myriotylum, the causal pathogen of ginger rhizome rot which occurs severely in fields was rarely detected from storage seed-rhizomes suggesting its minor involvement with storage rot. Pathogenic Pythium isolates were frequently obtained from both rhizome surface and inner tissues of rotten rhizomes. Detection frequency of Pythium isolates in inner tissues decreased as increasing distance from rhizome surface. In wound-inoculation tests, above pathogens caused a varying degree of rot on healthy rhizomes at 15$^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$ with increasing severity at higher temperatures.

• 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.

• 식물병연구
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• 제10권1호
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• pp.82-85
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• 2004

Erwinia carotovora subsp. carotovora에 의한 배추 무름병은 배추에서 가장 큰 문제가 되고 있는 병 중 하나이다. 본 연구는 칼슘비료 시비가 배추 무름병 발생에 미치는 영향을 조사하기 위하여 실시하였다 칼슘 비료 7종을 선발하여 배추 유묘에 엽면 살포한 후, 세균현탁액과 mineral oil을 4:1로 혼합하여 배추의 중앙 기부에 10 m1 관주 접종하는 mineral oil 접종법으로 접종하였다. 배추 유묘에 엽면 살포한 결과 calcium hydroxide가 다른 calcium 비료보다 무름병 방제에 효과가 높게 나타났다. 질소 비료시비는 무름병 발생을 촉진한 반면, calcium hydroxide를 수용액으로 엽면시비할 때 유묘에서뿐 아니라 포장 시험에서도 무름병 발생을 억제하였다. Calcium과 질소를 혼합 살포할 때도 calcium 단독살포와 마찬가지로 무름병 발생을 억제하였다.

• 한국연초학회지
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• 제7권2호
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• pp.123-128
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• 1985

The incitant of soft rot on burley tobacco leaves in the curing vinylhouse was identified as Erwinia carotovra subsp. carotovora on the basis of its physiological characters. The bacterium yew best at $25^{\circ}C$ and $30^{\circ}C$, but no growth was detectable at $40^{\circ}C$ in the nutrient broth for 24 hours period. Burley tobacco leaves inoculated with the bacteria (Ecc) produced typical soft rot lesions when the incubation temperature was 25 to $30^{\circ}C$ and the relative humidity was more than 8075, however, the lesion development was suppressed when the temperature was $40^{\circ}C$ and the relative humidity was below 80%. Significant negative correlation was found between hanging space in the curing vinylhouse and the incidence of soft rot on the tobacco leaves harvested in a rainy day regardless of streptomycin treatment.

• 식물병연구
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• 제29권1호
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• pp.64-71
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• 2023

In October 2021, soft rot disease seriously affected radish crop in Dangjin, Chungcheongnam-do, Korea. The infected radishes were stunted and turned dark green, with yellowish leaf foliage. A slimy, wet, and decayed pith region was observed in the infected roots. The bacterial strain KNUB-03-21 was isolated from infected roots. The biochemical and morphological characteristics of the isolate were similar to those of Pectobacterium brasiliense. Phylogenetic analysis based on the sequences of the 16S rRNA region and the concatenated DNA polymerase III subunit tau (dnaX), leucine-tRNA ligase (leuS), and recombinase subunit A (recA) genes confirmed that the isolate is a novel strain of P. brasiliense. Artificial inoculation of radish with P. brasiliense KNUB-03-21 resulted in soft rot symptoms similar to those observed in infected radish in the field; subsequently, P. brasiliense KNUB-03-21 was reisolated and reidentified. To our knowledge, this is the first report of P. brasiliense as a causal pathogen of radish soft rot in Korea.

• 식물병연구
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• 제29권4호
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• pp.445-451
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• 2023

Zamioculcas zamiifolia is a popular indoor ornamental plant in Korea. In August 2021, a severe outbreak of soft rot disease affected Z. zamiifolia in Emseong, Chungcheongbuk-do, Korea. Infected plants displayed wilting, water-soaked lesions, stem collapse, and green-brown discoloration. The bacterial strain KNUB-05-21 was isolated from infected stems and identified as Pectobacterium aroidearum using 16S rRNA nucleotide sequencing and multilocus sequence analysis based on partial sequences of dnaX, leuS, and recA genes. Confirmation of its affiliation with P. aroidearum was also obtained through biochemical and morphological characterization. To confirm the pathogenicity of strain KNUB-05-21, its suspension was injected into Z. zamiifolia stems. Within a week, soft rot developed on the stems, exhibiting symptoms similar to those observed in field-infected plants. The reisolated strain was identical to those of P. aroidearum. Before this study, P. aroidearum was not reported as a causative pathogen of Z. zamiifolia soft rot in Korea.