• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.147-152
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• 1984

Six hundred and twenty five isolates of Xanthomonas campestris pv. oryzae, cauing bacterial leaf blight (BLB) of rice, were classified into five pathotypes during $1979\~1983$ in Korea. Among them, 483 isolates$(77.3\%)$ were classified as pathotype I, 83 $(13.3\%)$ as pathotype II, 54$(8.6\%)$ as pathotype III, 3 $(0.5\%)$ as pathotype IV and 2$(0.3\%)$ as pathotype V. Pathotype I was the most prevalent throughout the country. Pathotype III was widely distributed in the western or southern parts of Korea, particularly in Jeonnam, Chungnam and Gyeongnam provinces. One isolate of pathotype IV was found in Gyeongnam in 1980, and two isolates were found in Jeonnam in 1981. Most of the isolates were obtained from Milyang 23 varietal group, while the isolates of pathotype III were collected from Yushin and Tongil varietal group.

• Research in Plant Disease
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• v.10 no.3
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• pp.194-197
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• 2004

Incidence of tobamovirus diseases was 100％ at late growth stage of green pepper on hydroponic systems in plastic house. Infection frequency of the diseases showed 34％ of Pepper mild mottle virus (PMMoV), 41.5％ of Tobacco mild green mottle virus (TMGMV), and 24.5％ of the co-infected viruses. The two viruses specifically reacted in DAS-ELISA prepared with each polyclonal antibody. A total of 77 pure tobamovirus isolates obtained from the crops was tested for pathotype determination. The isolation frequency of tobamovirus pathotype $P_{0}$ and $P_{1,2}$ was 61 ％ and 39％, respectively. All TMGMV isolates belonged to the pathotype $P_{0}$. In restriction enzyme analysis of the cDNAs synthesized with coat protein gene of PMMoV pathotype $P_{0}$ and $P_{1,2}$, the former had two TaqI sites but the later had one.one.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.303-307
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• 1998

Citrus scab caused warty and scabby lesions on the surface of leaves, twigs and fruits of Satsuma mandarin. Warty lesions were mainly developed before July but scabby ones were developed during summer season in Cheju island, Korea. The casual organism of scab was morphologically identified as Sphaceloma fawcettii and was thought to be Tryon's pathotype of Elsinoe fawcettii, because it was pathogenic on rough lemon and Cleopatra mandarin but non-pathogenic on sour orange, grapefruit and sweet orange among the 5 differential hosts of E. fawcettii.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.102-106
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• 1986

The 719 isolates of Xanthomonas campestris pv. oryzae collected in Honam district during 1980-1984 were classified with new differential cultivars: 466($64-.8\%$) were pathotype K1, 116$(16.1\%)$ pathotype K2, 130$(18.1\%)$ pathotyps K3, and 7$(1.0\%)$ pathotype K4. No isolate for pathotype K5 was found. The isolates of pathotypes K1, K2 and K3 were distributed in the geographic regions, Haenam, Gwangyang, Gangjin, Wando, Igsan, and Buan. The isolates of all pathotypes were obtained from Milyang 23, Nagdong, and Dongjin which were susceptible to all the pathotypestested, while most of the isolates belonging to pathotype K3 and K4 were obtained from pungsan, Baegyang, Samgwang and Milyang 30.

• Research in Plant Disease
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• v.19 no.2
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• pp.124-127
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• 2013

Black necrotic spots were observed from the fruits of paprika that were cultivating in a vinylhouse. The casual agents of the symptom were identified as several isolates of Pepper mild mottle virus (PMMoV) by responses of indicator plants, electron microscopy, and RT-PCR analysis. Symptoms of the viral disease were mild mottle in the young leaves, necrotic spots on the fruits and the fruit apex of paprika, but the symptoms were not shown on the mature leaves. All of the PMMoV isolates were determined as $P_{1.2.3}$ pathotypes from the biological responses on the chilli pepper lines used for discrimination of tobamovirus pathotypes. Pathogenicity of the PMMoV isolates was also confirmed using mechanical inoculation method to paprika seedlings. The coat protein (CP) genes of the PMMoV isolates were compared at the nucleotide and amino acid levels with the previously published PMMoV isolate. The isolates share 96 to 99% CP nucleotide identity among the isolates. The CP of $P_{1.2}$-pathotype PMMoV-P2 presented Met at position 139, But the CPs of $P_{1.2.3}$-pathotype PMMoVs from paprika showed Met to Asn substitution at the same position. This is the first report of identification of $P_{1.2.3}$-pathotype PMMoV isolates from paprika in Korea.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.318-323
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• 1995

The effect of AF-toxin I produced by the strawberry pathotype of Alternaria alternata on the protein synthesis of susceptible strawberry protoplasts was examined by using the radiolabeled amino acids. The incorporation of the radiolabeled amino acids into newly synthesized proteins in the strawberry protoplasts was stimulated by the toxin treatment at relatively low concentrations (2.2$\times$10-11 to 2.2$\times$10-9 M), but not at higher concentrations (2.2$\times$10-8 to 2.2$\times$10-6 M). An one-dimensional SDS-polyacrylamide gel electrophoresis revealed no detectable differences in the proteins synthesized in both the toxintreated and untreated protoplasts. The susceptible strawberry protoplasts were treated with AF-toxin I and stained with Fluostain I to detect the extracellular polysaccharides. The toxin treatment induced the accumulation of extracellular polysccharides in a dose-dependent manner. These results indicate a transient activation of cellular metabolism in the susceptible cells by the toxin exposure.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.530-534
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• 2001

A total of 23 isolates were obtained from seeds of 30 pepper cultivars by single lesion isolation on Nicotiana glutinosa. The isolates were tested for pathotype determination using standard pepper differentials. Two pathotypes of Tobamoviruses, namely P0 and P1.2 were detected from the pepper seeds, of which pathotype P1.2 was predominant. Pathotypes P1 and P1.2.3 were unable to detect in this study. All pepper cultivars except one showed resistance to two pathotypes, P0 and P1, but not to pathotype P1.2. These results could be useful for breeding Tobamovirus-resistant pepper and producing virus-free seed stock.

• The Plant Pathology Journal
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• v.34 no.6
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• pp.506-513
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• 2018

Clubroot is one of the most economically important diseases of the Brassicaceae family. Clubroot disease is caused by the obligate parasite Plasmodiophora brassicae, which is difficult to study because it is nonculturable in the laboratory and its races are genetically variable worldwide. In Korea, there are at least five races that belongs to four pathotype groups. A recent study conducted in Korea attempted to develop molecular markers based on ribosomal DNA polymorphism to detect P. brassicae isolates, but none of those markers was either race-specific or pathotype-specific. Our current study aimed to develop race- and isolate-specific markers by exploiting genomic sequence variations. A total of 119 markers were developed based on unique variation exists in genomic sequences of each of the races. Only 12 markers were able to detect P. brassicae strains of each isolate or race. Ycheon14 markers was specific to isolates of race 2, Yeoncheon and Hoengseong. Ycheon9 and Ycheon10 markers were specific to Yeoncheon isolate (race 2, pathotype 3), ZJ1-3, ZJ1-4 and ZJ1-5 markers were specific to Haenam2 (race 4) isolate, ZJ1-35, ZJ1-40, ZJ1-41 and ZJ1-49 markers were specific to Hoengseong isolate and ZJ1-56 and ZJ1-64 markers were specific to Pyeongchang isolate (race 4, pathotype 3). The PCR-based sequence characterized amplified region (SCAR) markers developed in this study are able to detect five Korean isolates of P. brassicae. These markers can be utilized in identifying four Korean P. brassicae isolates from different regions. Additional effort is required to develop race- and isolate-specific markers for the remaining Korean isolates.

• Research in Plant Disease
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• v.17 no.2
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• pp.191-195
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• 2011

This experiment was attempted to investigate a cause of the scion death in green pepper grafting system. A tobamovirus particle examined in the rootstock of the sample but not in the scion showing necrosis. The virus isolated from the rootstock was identified as Pepper mild mottle virus (PMMoV), pepper tobamovirus pathotype P1.2. (PMMoV-2), by nucleotide sequence analysis and host plant reaction. The virus isolate infected systematically in 6 commercial rootstock varieties using for green pepper grafting seedling production. Green pepper varieties 'Long green mart' and 'Daechan' represented resistance to the virus showing local lesions only on the inoculated leaves and 'Manitda' was systematically infected. In the experiment with grafting 'Long green mart' or 'Daechan' onto the those rootstocks, the upper leaves of the scions first showed vein necrosis and wilt symptoms 7 days after inoculation with PMMoV-2 on the cotyledon of the rootstock, following to the scion stem necrosis and then only the scion death. The virus was detected in the rootstock but not in the scion. However, 'Manitda' of susceptible variety in the grafting system showed mottle symptom on the leaves of the scion but not necrosis on the plant. PMMoV-3 isolate, pepper tobamovirus pathotype P1.2.3, did not cause the scion death in the grafting system. All of the varieties were susceptible to PMMoV-3. These results suggest that the scion death is caused by infecting with pepper tobamovirus pathotype P1.2. in the green pepper grafting system combined with the susceptible rootstock and the resistance scion to the virus pathotype.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.23-28
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• 1978

The study has been carried to confirm the pathotypes of Kresek inducing isolates of X. oryzae, and its reaction to the test plants when they were inoculated by the use of various methods. Induction of Kresek symptom by 23 isolates which randomly samplified from 123 Kresek areas through the country also were examined. The specificity of Pathotypes I, II, V in causing Kresek and the potenciality of infected rice straw is a first inoculum for Kresek epidemics in nature were tested. Fifteen out of 23 isolates from kresek area belonged to pathotype group I, while the rest of 8 isolates 5 howed group II reaction, and the most of isolates were originated from infected rice plant of Milyang #23. All of five pathotype groups were abled to produce 'Kresek' symptom although they showed some differences in each group of pathotype. The varieties Milyang #21, 22 and 23 were attacked by all isolates of group I, II and V while the Gogyoku group varieties including Yushin produced kresek symptom only by pathotype group II. Infected and dried straw maintained the pathogens during the winter period, and these straw acted as a first inoculum of Kresek disease when the straw were cutted and used as a manure just before transplanting of rice seedling.