• Research in Plant Disease
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• v.6 no.1
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• pp.15-18
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• 2000

A new bacterial disease was found on leaves of Kalanchoe blossfeldiana plant grown under vinyl-house condition in winter of 1998 in Taejeon. the first symptoms of the disease are the appearance of the water-soaked and light brown spots. Later they become soft rot with brown color. Causal bacteria were isolated from diseased tissues and the same symptoms as the natural infection were developed on Kalanchoe blossfeldiana leaves by needle-prick inoculation. The causal bacterium was identified Erwinia hervicola by its bacteriological characteristics. This is the first reported of this bacterium to occur on kalanchoe blossfeldiana plant in Korea. Therefore, we proposed to name the diseases as \"bacterial soft rot of Kalanchoe blossfeldiana\" by E. herbiocla.

• Journal of Life Science
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• v.31 no.7
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• pp.609-616
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• 2021

Bacterial soft rot, caused by Pectobacterium carotovorum subsp. carotovorum (Pcc), is one of the destructive diseases of radish (Raphanus sativus) in Asian countries. The objective of this study was to establish an efficient bioassay method for the evaluation of bacterial soft rot resistance in commercial radish cultivars. First, an efficient bioassay method for examining resistance to bacterial soft rot in commercial radish cultivars was investigated. Six commercial radish cultivars were tested under various conditions: two temperatures (25℃ and 30℃), three inoculations methods (drenching, spraying, and root dipping), and two growth stages (two- and four-leaf stages). The results suggested that spraying with 1×10⁶ cfu/ml of bacterial inoculums during the four-leaf stage and incubating at 30℃ could be the most efficient screening method for bacterial soft rot resistance in commercial radish cultivars. Second, we investigated the degree of resistance of 41 commercial radish cultivars to five Pcc isolates, namely KACC 10225, KACC 10343, KACC 10421, KACC 10458, and KACC 13953. KACC 10421 had the strongest susceptibility in terms of moderately resistant disease response to bacterial soft rot. Out of the 41 radish cultivars, 13 were moderately resistant to this pathogen, whereas 28 were susceptible. The moderately resistant radish cultivars in this investigation could serve as resistance donors in the breeding of soft rot resistance or could be used to determine varietal improvement for direct use by breeders, scientists, farmers, researchers, and end customers.

• Life and Agrochemicals
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• v.27 no.4 s.217
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• pp.44-45
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• 2006

• Research in Plant Disease
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• v.6 no.1
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• pp.1-5
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• 2000

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2006.06a
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• pp.19.2-20
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• 2006

• Korean journal of applied entomology
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• v.41 no.4
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• pp.279-284
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• 2002

Flacherie symptom was found in the fifth instar larvae of silkworm, Bombyx mori. The bacterial pathogen was isolated from the hemolymph of the infected silkworm and identified. The isolated bacteria caused a significant flacherie pathogenicity to the fifth instar larvae of B. mori when $5{\times}10^{6}$ cfu (colony-forming unit) of the bacteria was injected into each larva. The infected larvae began to die at 6 days after injection and resulted in complete mortality at 10 days. The bacterium was identified as Staphylococcus gallinarum based on the morphological and physiological characteristics described in Bergey's manual. This identification was further supported by the characters of carbohydrate utility analyzed from a bacterial identification system ($MicroLog^{\circledR}$) and also by the molecular structure of 165-23S rDNA internal transcribed spaces. As an insecticidal action, S. gallinarum caused hemolymph septicemia by its cytotoxic effect on the hemocytes of B. mori.

• Research in Plant Disease
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• v.26 no.3
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• pp.159-169
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• 2020

Pectobacterium carotovorum subsp. carotovorum (Pcc) causes bacterial soft rot on a wide range of crops worldwide, especially in countries with warm and humid climates. This study was conducted to establish an efficient screening method for resistant cultivars of Chinese cabbage to bacterial soft rot. Resistance degrees of 65 commercial Chinese cabbage cultivars to the Pcc KACC 10225 isolate were investigated. For further study, three Chinse cabbage cultivars (Taebong, Hadaejangkun, CR Alchan) showing different level of resistance to the bacterium were selected. The development of bacterial soft rot on the cultivars was tested according to several conditions such as growth stage of Chinse cabbage seedling, inoculum concentration, and incubation temperature after inoculation. On the basis of the results, we suggest that an efficient screening method for resistant Chinses cabbage to Pcc is to inoculate twenty one-day-old seedlings with a bacterial suspension of Pcc at a concentration of 1×10⁷ cfu/ml, and to incubate the plants in a dew chamber at 25℃ for 24 hr and then to cultivate in a growth room at 25℃ and 80% relative humidity with 12-hr light per day.

• Research in Plant Disease
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• v.24 no.3
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• pp.193-201
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• 2018

Pectobacterium carotovorum subsp. carotovorum (Pcc) causes bacterial soft rot on a wide range of crops worldwide, especially in countries with warm and humid climates. This study was conducted to establish an efficient screening method for resistant cultivars of radish (Raphanus sativus) to bacterial soft rot. Resistance degrees of 60 commercial radish cultivars to the Pcc KACC 10421 isolate were investigated. For further study, six radish cultivars (Awooriwoldong, YR Championyeolmu, Jeonmuhumu, Bitgoeunyeolmu, Sunbongaltari, Housecheongok) showing different level of resistance to the bacterium were selected. The development of bacterial soft rot on the cultivars was tested according to several conditions such as incubation temperature, seedling stage of radish, inoculum concentration to develop the disease. On the basis of the results, we suggest that an efficient screening method for resistant radish to Pcc is to inoculate twenty-day-old seedlings with a bacterial suspension of Pcc at a concentration of $8{\times}10^5cfu/ml$ and then to cultivate the plants in a growth room at $25^{\circ}C$ and 80% RH with 12-hour light per day.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.325-331
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• 2009

Three beneficial bacterial agents, Lactobacillus strain KLF01, Lactococcus strain KLC02 and Paenibacillus strain KPB3 were showed clear zone against plated Pectobacterium carotovorum subsp. carotovorum (Pcc) soft rot pathogen. In greenhouse test, bio-control efficacy was more significantly effective in the treatments by KLC02 and KPB3 as 64%, 50%, 56% and 66%, 57%, 58% according to date of evaluation, respectively. In case of KLF01 control effect was relatively lower than treatments of KLC02 and KPB3 but its efficacy was still significantly observed when compared to control (only water treatment). Furthermore, KLF01, KLC02 and KPB3 showed 55%, 60% and 62% bio-control efficacy, respectively in field test from early March to late July of 2009. Thus, we suggest that these strains can be useful as bio-control agents against soft rot caused by Pcc.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.618-623
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• 2015

The new white calla lily (Zantedeschia aethiopica) cultivar 'White Cutie' was bred at the National Institute of Horticultural & Herbal Science (NIHHS) in 2011. 'Childsiana' showing the multi-flowering characteristic and 'Wedding March' resistant to soft rot disease were artificially crossed in 2004. Of the progeny, 'White Cutie' was selected specifically for use in cut flower production after investigation over seven years (2005 to 2011) of genetic and phenotypic characteristics, resistance against soft rot, and customer preference regarding the culture vigor and post-harvest quality. 'White Cutie' was early flowering (85.6 days to flowering) with white flowers (RHS W155C), although it had a mid-sized flower in which spathe height and width were 8.6 cm and 8.7 cm, respectively. It was multi-flowering (6.2 flowers per plant) and produced a very high number of cormels (13.4 per plant). Furthermore, it was resistant to soft rot disease.