• The Plant Pathology Journal
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• v.21 no.4
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• pp.310-316
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• 2005

The objectives of this study were to identify the aecial host ranges of four Korean Gymnosporangium species, G. asiaticum, G. cornutum, Gjaponicum and Gyamadae, and to verify the morphological characteristics of telia as diagnostic keys to the species. Thirteen Korean Rosaceous woody species were artificially inoculated with teliospores obtained from Juniperus species. There was high specificity between telial and aecial hosts and the fungal species, providing the first experimental proof on host alternation of these rust fungi in Korea. Telia on the witches' broom and on the small galls were identified as new telial characteristics in G asiaticum and in G. yamadae, respectively. Aecial hosts of G. asiaticum and G. yamadae showed varying responses in their susceptibility and in the days required for formation and duration of spermogonia and aecia after inoculation. Four telial host species in Juniperus were confirmed for the first time in Korea, which include J. chinensis var. kaizuka, J. chinensis var. horizontalis and J. chinensis var. globosa for G. asiaticum; and J. chinensis var. kaizuka for G. yamadae.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.383-385
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• 1995

Occurrence of white scab of tea (CAmellia sinensis) showing numerous, small, circular, reddish or yellowish brown spots on young tea leaves was observed at a tea plantation of Boseung, Chonnam, from May to June in 1992-1994. At the late growth stages, the center of the spot became light gray. The causal fungus of the white scab was identified as Sphaceloma theae Kurosawa. Symptoms were produced 5∼6 days after inoculation by the artificial inoculation of s. theae conidia, which was similar to those on naturally infected leaves.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.236-241
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• 2001

Serve outbreaks of anthracnose were observed on perilla plants grown in greenhouses and open fields in several locations in Korea during the disease survey from 1997 to 2000. A total of 53 isolates of Colletotrichum spp. and Glomerella sp. was obtained from diseased perilla plants and identified based on their morphological and cultural characteristics. Forty isolates were identified as Colletotrichum gloeosporioides, three isolates as C. coccodes, five isolates as C. dematium, and the other five isolates as Glomerella cingulata, the teleomorph of C. gloeosporioides. All isolates of C. gloeosporioides tested by artificial inoculation were strongly virulent on perilla plants, but isolates of the other species were weakly or not virulent. Anthracnose symptoms induced on the perilla plants by artificial inoculation with the isolates of C. gloeosporioides were similar to those observed in the fields. This study revealed that C. gloeosporioides is the main causal fungus of perilla anthracnose.

• Mycobiology
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• v.42 no.4
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• pp.331-338
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• 2014

To examine the effects of water stress and Cenangium ferruginosum (CF) on the fungal endophytic community of needles of Pinus koraiensis (PK), fungal endophytes isolated from the needles of 5-year-old PK seedlings were compared before and after exposure to water stress conditions and artificial inoculation with CF ascospores. Artificial CF inoculation was successfully confirmed using PCR with CF-specific primers (CfF and CfR). For comparison of the degree of water deficit in water-stressed and control groups of PK seedlings infected with CF, the water saturation deficit and water potential were measured. Lower water potential estimates were found in the water-stressed seedlings than in the control group. The fungal endophytes isolated from the second-year needles of non-water-stressed seedlings before and after CF inoculation revealed that primary saprobes were approximately 30% and 71.7%, respectively, and the remaining endophytes were rot fungi or pathogens. Sixty days after CF inoculation, diverse fungal endophytes in the first-year needles were isolated from the water-stressed seedlings. However, some fungal endophytes isolated from the non-water-stressed seedlings were also identified. Fungal endophytes in the second-year needles of the water-stressed and non-water-stressed seedlings were approximately 8% and 71.7% of saprobes, respectively, and the remaining endophytes were rot fungi or pathogens. On the basis of the results, we conclude that water deficit and CF can have an effect on fungal endophytic communities in the needles of PK seedlings.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.85-89
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• 1997

Etiological components of the rice cultivars possessing durable resistance to rice blast were evaluated. In the greenhouse test by artificial inoculation, number of leaf blast lesion in Dongjinbyeo was not increased by any race of the pathogen, while the lesion number on the resistant cultivar Palgongbyeo and susceptible cultivar Jinmibyeo was increased rapidly. Size of the lesion in Dongjinbyeo was smaller and progressed more slowly than the resistant cultivar Palgongbyeo until 11 days after inoculation. Latent period in Dongjinbyeo was intermediate. However, the period was significantly variable depending upon the races. Least amount of conidia was produced in Dongjinbyeo by race KJ-107 and the number of conidia was decreased rapidly from 11 days after inoculation.

• Mycobiology
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• v.35 no.2
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• pp.54-61
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• 2007

Two isolates of Tricholoma matsutake T-008 and T-034, preserved in Entomopathogenic Fungal Culture Collection (EFCC) of Korea, were used in the present study. The isolates had 100% Bootstrap homology with Tricholoma matsutake U62964 and T. matsutake AB188557 and AF309538 preserved in Gene Bank of NCBI. Mycelial growth of T. matsutake was highest in TMM and MYA at $25^{\circ}C$. The highest dry wt. of mycelium was obtained after 65 days of culture, when 6 mycelial discs were inoculated in 100 ml of broth in 250 ml shaking flask. Mycelial mats were observed in clumped condition at the inoculation sites of pine forest after two weeks of inoculation. After 5 months of inoculation, mycelia mats were observed growing inside soil and walls of a few inoculation sites, while mycelial mats growth up to $5{\sim}8$ cm were observed in the roots of pine tree after 6 months. The survival rate of the inoculum was about 40% of the total inoculation sites. The survival rate was found below 20% when the mycelium was inoculated in the summer. The reasons for low survival rates of the mycelium were mainly due to dry season and the soil-borne small animals such as earthworm and mole. After one year of inoculation, no external difference was observed between the artificially inoculated mycelia and the naturally existing mycelia of T. matsutake. The present study showed that fruiting bodies of T. matsutake could be produced by artificial inoculation under the appropriate environmental conditions.

• Journal of Sericultural and Entomological Science
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• v.44 no.2
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• pp.74-81
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• 2002

The optimal conditions for mycelial growth of P. linteus ASI 26011 were 25-30$^{\circ}C$ and pH 6.0, respectively. The mycelial growth of P. linteus was excellent on MCM medium. In case of carbon sources, the mycelial growth of P. linteus was best on the culture media that were contained with sucrose, mannose and glucose. Potassium nitrate and sodium nitrate were good for the mycelial growth of P. linteus as a nitrogen source. For comparison of the mycelial colonization of P. linteus on logs, several techniques of inoculation were tested; the sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation. The mycelial colonization of P. linteus on logs was good in the treatment of sterilized short log inoculation, but poor in the traditional methods such as drilling inoculation and log-end sandwich. The initial mycelial growth and the full mycelial colonization of P. linteus were the best on 20 cm logs under the condition of 42% of moisture content in log. Also the initial mycelial growth of P. linteus was accelerated over 12 hours of sterilization. Burying method of logs after 5-6 months of incubation was the best for formation of basidiocarp of P. linteus. The formation of fruiting body of P. linteus was quite good in the cultivation house at the 31-35$^{\circ}C$ and over 96% of relative humidity.

• Research in Plant Disease
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• v.30 no.1
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• pp.13-19
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• 2024

In July 2022 and 2023, black mold symptoms were observed sporadically on fruits of sweet pepper (Capsicum annuum) plants grown in a greenhouse located in Suwon, Korea. The incidence of black mold on the fruits was 5-24% (average 14.8%) in variety SP-504 (yellow and elongate type) and 1-8% (average 5%) in variety SP-505 (red and round type) investigated. Four single-conidium isolates of Alternaria sp. obtained from the diseased fruits were identified as Alternaria alternata based on the morphological characteristics and molecular phyogenetic analyses. The isolates were tested for pathogenicity to sweet pepper fruits of varieties SP-504 and SP-505 through artificial inoculation. The isolates mostly induced large lesions on fruits of the two varieties in the wound inoculation, but only two isolates small lesions on fruits of the variety SP-504 in the non-wound inoculation. No lesions formed on fruits of the variety SP-505 in the non-wound inoculation. The pathogenicity tests revealed that susceptibility of sweet pepper fruits to the disease differs between the varieties. The symptoms induced by pathogenicity tests with the isolates were similar to those observed on fruits from the greenhouse investigated. This is the first report of A. alternata causing black mold on sweet pepper fruits in Korea.

• Proceedings of the Plant Resources Society of Korea Conference
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• 1998.10a
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• pp.126-128
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• 1998

• The Plant Pathology Journal
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• v.18 no.4
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• pp.225-227
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• 2002

Moth orchid plants with yellowing blight and root rot symptoms were collected, and a total of 54 isolates of Fusarium spp. was obtained from roots and leaf bases of the diseased plants. The isolates were identified based on their morphological characteristics. Out of the 54 isolates of Fusarium spp., 42 isolates were identified as F. solani, 5 isolates as F. oxysporum, and 7 as F. proliferatum. Isolates of the three Fusarium spp. were tested for pathogenicity to moth orchid plants by artificial inoculation. All the Fusarium spp. induced root rot of the host plants. The symptoms progressed up to the basal part of the leaves, which later caused yellowing blight. The symptoms induced on the plants by artificial inoculation with the Fusarium spp. isolates were similar to those observed in greenhouses. The present study reveals that F. oxysporum, F. proliferatum, and F. solani cause root rot of moth orchid, and that F. solani is the main pathogen of the disease.