• Research in Plant Disease
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• v.17 no.3
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• pp.396-398
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• 2011

Soft rot disease on Raspberry (Rubus crataegifolius Bunge) was observed in sale boxes at Jinju City Wholesale Market of Agricultural Products in June 2010. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The colonies on the infected fruits were white to light brown, formed numerous sporangiospores. Optimum temperature for the mycelial growth of the causal fungus on PDA was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangia were globose, white at early and gradually to black, and 40-210 ${\mu}m$ in diameter. Sporangiophores were white to mid brown as maturation and 8-20 ${\mu}m$ in diameter. Columella were globose to sub-globose, and the size of the diameter was 85-120 ${\mu}m$ in diameter. Sporangiospores were sub-globose, rhomboidal and irregular, streaked and 5-10 ${\mu}m$ in length. On the basis of symptom, mycological characteristics, ITS rDNA sequence analysis, and pathogenicity of the fungus, the causal fungus was clearly identified as Rhizopus oryzae Went & Prinsen Geerligs. This is the first report of soft rot by R. oryzae on R. crataegifolius in Korea.

• 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.

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.62-68
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• 2011

Calmodulin (CaM), a $Ca^{2+}$ binding protein in eukaryotes, mediates cellular $Ca^{2+}$ signals in response to a variety of biotic and abiotic external stimuli. The $Ca^{2+}$-bound CaM transduces signals by modulating the activities of numerous CaM-binding proteins. As a CaM binding protein, AtCBP63 ($\b{A}$rabidopsis thaliana $\b{C}$aM-binding protein $\underline{63}$ kD) has been known to be positively involved in plant defense signaling pathway. To investigate the pathogen resistance function of AtCBP63 in potato, we constructed transgenic potato (Solanum tuberosum L.) plants constitutively overexpressing AtCBP63 under the control of cauliflower mosaic virus (CaMV) 35S promoter. The overexpression of the AtCBP63 in potato plants resulted in the high level induction of pathogenesis-related (PR) genes such as PR-2, PR-3 and PR-5. In addition, the AtCBP63 transgenic potato showed significantly enhanced resistance against a pathogen causing bacterial soft rot, Erwinia carotovora ssp. Carotovora (ECC). These results suggest that a CaM binding protein from Arabidopsis, AtCBP63, plays a positive role in pathogen resistance in potato.

• Research in Plant Disease
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• v.13 no.1
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• pp.57-60
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• 2007

A rhizopus soft rot caused by Rhizopus stolonifer occurred sporadically on grape in orchard in Gyeongsang-nam-do Agricultural Research and Extension Services and in Wholesale Market of Agricultural Products in Jinju city. The infected fruits were rapidly water-soaked, softened and eventually rotted, and the symptoms were initiated from wounds or cracks occurred at harvest time. Sporangiophores were $850{\sim}1,800{\mu}m$ in length and $12{\sim}23{\mu}m$ in width. Sporangia were globose or hemispheric and $80{\sim}190{\mu}m$ in size. The color of sporangia was white and cottony at first and gradually to brownish black, bearing abundant spores when it matured. Columella were hemispheric and $70{\sim}95{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $8{\sim}22{\times}6{\sim}10{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was 25$^{\circ}C$. On the basis of mycological characteristics and pathogenicity to grape (Vitis vinifera), the causal fungus was identified as Rhizopus stolonifer (Ehrenberg ex. Fr,) Lind. This is the first report of Rhizopus soft rot by R. stolonifer on grape (V. vinifera) in Korea.

• Research in Plant Disease
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• v.14 no.1
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• pp.57-60
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• 2008

A rhizopus soft rot caused by Rhizopus stolonifer occurred sporadically on apple fruits (Malus pumila var. dulcissima Koidz.) at a wholesale market of agricultural products in Jinju, Korea in 2006 and 2007. Infected fruits were rapidly water-soaked, softened and rotted. The symptoms were initiated mainly from wounds or cracks occurred at harvest time. Sporangiophores were $950{\sim}1,900\;{\mu}m$ in length and $12{\sim}22\;{\mu}m$ in width. Sporangia were globose or hemispheric and $82{\sim}185\;{\mu}m$ in size. The color of sporangia was white and cottony at first and gradually turned to brownish black, bearing abundant spores when matured. Columella were hemispheric and $70{\sim}85\;{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $8{\sim}18{\times}7{\sim}8\;{\mu}m$ in size. Optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. On the basis of mycological characteristics and pathogenicity to apple the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill. This is the first report of Rhizopus soft rot by R. stolonifer on Fuji apple in Korea.

• 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.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.433-441
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• 2022

Bacterial phytopathogen Pectobacterium causes soft rot disease in several vegetable crops globally, resulting in heavy agricultural losses at both the pre and postharvest stages. The present work was carried out to screen Kimchi cabbage genetic resources conserved at the National Agrobiodiversity Center, Rural Development Administration, Korea, for resistance against the soft rot pathogen Pectobacterium carotovorum subsp. carotovorum KACC 21701 over a period of three years (from 2020 to 2022). Infection of the phytopathogen was carried out at four-leaf stage and for each accession, twenty-five plants per germplasm were infected with KACC 21701. Kimchi cabbage cultivars Wangmatbaechu, Seoulbaechu, and CR Kiyoshi were used as control. Seven-days post-infection, the Disease Index (DI) values were manually recorded from zero to four, zero matched perfectly heathy plants and four completely dead plants. The 682 accessions of Kimchi cabbage exhibited varying degrees of disease resistance to KACC 21701 and thirty accessions, exhibiting a DI≤2, were considered for replication studies. During the replication studies, four landrace germplasms (IT102883, IT120036, IT120044, and IT120048) and one cultivar(IT187919) were confirmed to be moderately susceptible to KACC 21701. Results of the preliminary screening as well as replication studies were documented for the all the 682 germplasms. Addition of such information to the passport data of stored germplasms might serve as potential bio-resource for future breeders and researchers to develop resistant varieties or study the mechanisms involved in resistance of plants to such phytopathogen.

• Research in Plant Disease
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• v.17 no.2
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• pp.232-234
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• 2011

During survey of postharvest diseases of vegetables in the middle region of Korea in 2003, 2004 and 2005, new disease symptoms showing watery rot and soft rot were observed. In this study, the disease causal agents were identified as Geotrichum candidum, and their host range and pathogenicity were investigated. G. candidum isolated had wide host range and strong pathogenicity against carrot, cucumber, tomato and pumpkin. The disease occurrence on several vegetables that G. candidum can be a serious threat to stable production of fresh vegetable.

• Research in Plant Disease
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• v.8 no.2
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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.