• Mycobiology
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• v.29 no.3
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• pp.176-178
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• 2001

A soft rot of fruits caused by Rhizopus stolonifer occurred on cherry tomato in Jinju City Agricultural Products Wholesale Market, Korea. The disease infection usually started from wounding after cracking of fruits. At first, the lesions started with water soaked and were rapidly softened and diseased lesion gradually expanded. The mycelia grew vigorously on the surface of fruits and formed stolons. Colonies on potato dextrose agar at $25^{\circ}C$ were white cottony at first, becoming heavily speckled by the presence of sporangia and the browinish black, and spreading rapidly by means of stolons fired at various points to the substrate by rhizoids. Sporangia were $82.7{\times}196.7{\mu}m$ in size and globose or sub-globose with somewhat flattened base. The color of sporangia was white at first and then turned black with many spores, and never overhanging. Sporangiophores were $2.6{\sim}5.8{\times}12.3{\sim}24.2{\mu}m$ in width, smooth-walled, non-septate, tight brown, simple, long, arising in groups of $3{\sim}5$ from stolons opposite rhizoids. Sporangiospores were $8.2{\sim}18.8{\mu}m$ long, irregular, round, oval, elongate, angular, and browinish-black streaked. Columella was $64.1{\times}136.3{\mu}m$. brownish gray, and umberella-shaped when dehisced. The causal organism was identified to be R. stolonifer. This is the first report of Rhizopus soft rot on cherry tomato caused by R. stolonifer in Korea.

• The Plant Pathology Journal
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• v.19 no.2
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• pp.79-84
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• 2003

Sclerotinia rot occurred severely on some vegetable crops grown in Namyangju, Yangpyung, and Yangiu areas in Korea in 2001-2002. The crops infected with Scterotinia sp. were Adenophora remotiflora, Armoracia lapathfolia, Angelica acutiloba, Angelica archangelica, Anthriscus sylvestris, Aster tataricus, Beta vulgaris var. cicla, Brassica campestris var. marinosa, Brassica juncea var. laciniata, Chicholium intybus, Lactuca indica var. dracoglossa, Lactuca sativa var. oak-leaf, Petroselinum crispum, and Phyteuma japonicum. The fungus associated with the disease was identified as Sclerotinia sclerotiorum, based on the morphological characteristics of the pathogen. The symptoms were water-soaked spots that enlarged later and became a watery soft rot. Infected parts became yellow and then turned brown, followed by death of the whole plant. White mycelia developed on the upper petioles and leaves and on the soil where these plant parts lay. Then black sclerotia in variable size and shape formed from the mycelial mass. Pathogenicity of the fungus was proven by artificially inoculating each crop. This is the first report of Sclerotinia rot on the listed vegetable crops in Korea.

• Mycobiology
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• v.35 no.1
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• pp.30-35
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• 2007

The fruits showing brown rot symptom on dwarf flowering almond were found in Gongju, Chungchungnam-Do in Korea in July 2005. Small water-soaked lesions on the fruits were initiated, and gradually developed to soft rot covered with gray conidia. Then the diseased fruits were shrunk and became grayish-black mummies. A fungus was isolated from the diseased fruit and its morphological, cultural and molecular genetic characteristics were investigated. Typical blastospores of Monilinia spp. were observed under a light microscope both from tissues of the diseased fruits and from PDA-grown cultures. The fungus grew well at $25^{\circ}C$ and on PDA. The ITS ribosomal DNA region (650 bp) of the fungus was amplified by PCR and analyzed. Comparative data on ITS sequence homology among Monilinia spp., ITS sequence-based phylogram and morphological characteristics showed that the fungus is Monilinia fructicola. This is the first report on Monilinia fructicola causing brown rot on fruits of dwarf flowering almond in Korea.

• The Korean Journal of Mycology
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• v.51 no.2
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• pp.141-146
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• 2023

Stem rot symptoms were observed in Gondre (Cirsium setidens) plants growing in a vinyl greenhouse in Taebaek, Korea during a disease survey in June 2022. The plants presented with dark brown to black rot on the stems at or above the soil line. Severely diseased plants displayed wilt and blight. Disease incidence among these plants ranged from 1 to 5%. Three isolates of Rhizoctonia sp. were obtained from the stem lesions of diseased plants. All isolates were identified as Rhizoctonia solani AG-2-2(IV) based on the morphological and cultural characteristics, results of the anastomosis test, and phylogenetic analysis. The pathogenicity of the isolates to Gondre plants was confirmed using an artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated vinyl greenhouse. Here, we report a case of R. solani AG-2-2(IV) causing stem rot in Gondre.

• The Korean Journal of Mycology
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• v.50 no.3
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• pp.249-254
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• 2022

In June 2021, foot rot symptoms were observed in wasabi (Eutrema japonicum) plants growing in vinyl greenhouses of the Alpine Agricultural Experiment Station, Wild Vegetable Research Institute, in Taebaek, Gangwon Province, Korea. Diseased plants displayed black soft rot of crowns and petioles at the soil line and wilted. The incidence of diseased plants was 2-10% in four out of five vinyl greenhouses investigated. Eight fungal isolates were obtained from diseased plants. All the isolates were identified as Phytophthora pseudocrytogea based on their morphological characteristics and phylogenetic analysis. Three isolates of P. pseudocrytogea were used for pathogenicity test on wasabi plants via artificial inoculation. The pathogenicity of the isolates was confirmed in the inoculated wasabi plants. The symptoms shown by the inoculated plants were similar to those observed in plants from the investigated vinyl greenhouses. This is the first report of P. pseudocryptogea causing Phytophthora foot rot in wasabi.

• Agrochemical news magazine
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• v.25 no.3 s.196
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• pp.41-43
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• 2004

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.28-32
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• 2016

This experiment was carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Black Magic') in highlands. To achieve the research purpose, growth of 'Black Magic' Calla influenced by tuber hardness (3.3 and $6.0kg/cm^2$), $GA_3$ concentration (0, 100 and $200mgL^{-1}$), duration of $GA_3$ treatment (24 hr, 12 hr and 30min before planting) were investigated. When tubers have high hardness, those were not severely injured by soft rot disease regardless of $GA_3$ concentrations and treatment durations. Tubers with low tuber hardness showed more than 90% of soft rot occurrence when treated with $200mgL^{-1}$ $GA_3$ for 24 hrs before planting. However, soft rot did not occur when tubers were treated with $200mgL^{-1}$ $GA_3$ for 12 hrs before planting. In conclusion, $GA_3$ treatment results showed soft rot occurrence statistically significant degree in accordance with the bulbs hardness. In addition, the yield of the cut flowers is the result received the greatest effect in accordance with the bulbs in size and appeared to not be determined in accordance with the $GA_3$ treatment concentration and hardness bulbs. To obtain flowers without soft rot symptom, tubers (as $6.0kg/cm^2$) should be completely dried after $GA_3$ treatment.

• Mycobiology
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• v.32 no.2
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• pp.98-101
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• 2004

A fruit soft rot caused by Mucor piriformis occurred on sweet persimmon storages in Jinju, Changwon and Gimhae, Gyeongnam province, Korea, 2003. The disease infection usually started from wounding after cracking of fruits. At first, the lesions started with water soaked and rapidly softened and diseased lesion gradually expanded. Colonies on potato dextrose agar at $20^{\circ}C$ were whitish to olivaceous-buff Sporangia were globose, black and $96{\sim}153{\mu}m$ in size. Sporangiophores were $26{\sim}42{\mu}m$ in width. Sporangiospores were ellipsoid and $5.8{\sim}10.6{\times}4.3{\sim}7.6{\mu}m$ in size. Columella was obovoid, cylindrical-ellipsoidal, pyriform, subglobose and $80{\sim}125{\mu}m$ in size. Optimal temperature for mycelial growth was $20^{\circ}C$ on PDA. The causal organism was identified as M. piriformis. This is the first report of fruit soft rot on sweet persimmon caused by M. piriformis in Korea.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.741-743
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• 1998

A bacterial disease of pepper (Capsicum annuum L.) that rooted the stem nodes to black was found in pepper plants which cultivated in plastic house at Chungdo, Kyungpook, Korea in March, 1998. Bacterial isolates derived from the diseased peppers were pathogenic to potato, eggplant and Chinese cabbage but, was not pathogenic to chrysanthemum by artificial inoculation. On the basis of bacteriological characteristics and pathogenicity test on host plants, the causal organism of the node soft rot of pepper is identified as Erwinia carotovora subsp. carotovora and the name of disease is proposed as bacterial node soft rot of pepper.

• Research in Plant Disease
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• v.29 no.2
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• pp.184-187
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• 2023

In May 2020, we surveyed disease occurrence on vegetables grown in Seosan area, Korea. During the disease survey, white rot symptoms were observed in Korean wild chive (Allium monanthum) plants growing in fields. The symptoms occurred mainly in the seed bulb-producing fields of the crop. The above ground parts of the diseased plants displayed premature yellowing and dying of older leaves and stunting of the plants. The bulbs and roots of the diseased plants turned black and rotted. The disease occurred in a range of 1-60% in four of the eight fields surveyed. Three isolates of Sclerotium sp. were obtained from the bulb lesions of diseased plants. All isolates were identified as Stromatinia cepivora based on the morphological characteristics and phylogenetic analysis. Pathogenicity of the isolates on Korean wild chive was confirmed by artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated fields. This is the first report of S. cepivora causing white rot in Korean wild chive.