• Plant Disease and Agriculture
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• v.5 no.2
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• pp.105-110
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• 1999

Bacterial leaf spot by Xanthomonas campestris pv. vesicatoria has been known to cause serious problem in red pepper in Korea. However recent survey showed that most smptoms in the leaves were mixed with two different symptoms one was leaf spot and the other was canker. bacteria isolated from canker were identified as Clavibacter michiganensis subsp. michiganensis on the basis of biochemical and physiological characteristics. The causal bacteria were non-motile rod-shaped and Gram-positive. The lesions on pepper leaves appeared at first as small blisters or pimple-like white spots which enlarged in size at a later stage. The centers of some of the spots became necrotic and brown and were surrounded by a white halo. Pathogenicity tests were performed on pepper cv. Alchan seedling by spraying of bacterial suspension. During 1997 and 1998 total 17% of 527 fields surveyed were infected by C. michiganensis subsp. michiganensis. The canker of red pepper caused by C. michiganensis subsp. michiganensis was first identified in this study in Korea, and new name "gueyangbyung" was tentatively given to the disease.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.336-338
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• 1994

In 1991, the leaf brown spot of ivy-aureus (Scindapsus aureus) was found in Taejon and Seoul, Korea. The symptoms were appeared as dark-brown spots. The lesions were often surrounded by yellowish halos. These spots were enlarged to circular or elliptical in shape and dark-brown to black in color with slightly elevated in margin and sunken in center. The pathogenic bacteria were isolated from the diseased leaf of ivy-aureus were identified as Erwinia chrysanthemi on the basis of bacterial characteristics therefore, we would like to propose to the name of ivy-aureus disease caused by E. chrysanthemi as“bacterial brown rot of ivy-aureus”hereafter.

• Research in Plant Disease
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• v.21 no.2
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• pp.89-93
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• 2015

This study was carried out to develop the economic thresholds for the control of bacterial spot of red pepper. The correlation between diseased leaf rate and yield in field was Y=-0.724X+281.58, $R^2=0.78$, $r=-0.88^{**}$. The correlation between diseased leaf rate and yield loss in field was Y=0.813X+15.95, $R^2=0.78$, $r=0.88^*$.We found that control thresholds was below 30.3% diseased leaves rate per plant in field. The economic control thresholds for bacterial spot of red pepper was below 16.3%.

• Research in Plant Disease
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• v.25 no.2
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• pp.62-70
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• 2019

The global warming by increased $CO_2$ will effect of plant pathogenic microorganisms and resistance of host plants, and it is expected to affect host-pathogen interactions. This study used Capsicum annuum L. and Xanthomonas euvesicatoria, a pathogenic bacteria of pepper, to investigate interactions between hosts and pathogens in a complex environment with increasedcultivation temperature and drought stress. As a result, the bacterial spot disease of C. annuum L. caused by X. euvesicatoria was $35^{\circ}C$ higher than $25^{\circ}C$. In addition, the effect on water potential on bacterial spot disease was much greater water potential -150 kPa than -30 kPa. The disease progress and severity higher than water potential -30 kPa. This result will useful for understanding interaction with red pepper and X. euvesicatoria under the complex environment with increased cultivation temperature and in water potential -150 kPa drought stress in the future.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.360-366
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• 2011

Bacterial leaf spot of Euphorbia pulcherrima has been reported in many countries. Characterization by polyphasic approaches indicated that the isolates from India, USA and New Zealand could be distinguished based on rep-PCR profiles and gyrB phylogenies, while the Chinese isolates should be ascribed to Xanthomonas axonopodis pv. poinsettiicola.

• Research in Plant Disease
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• v.20 no.3
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• pp.211-215
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• 2014

This research was performed to examine the protective activities of the mixtures of pine oil and copper hydroxide against bacterial spot and anthracnose on pepper plants. As for bacterial spot, the treatment of pine oil alone displayed high disease incidence (59.6%) and low protective effect (28.9%). In comparison, the treatments of mixtures and copper hydroxide alone showed protective activities of 66.8-76.1%. The mixture of pine oil and copper hydroxide (4:1) suppressed the most effectively bacterial spot on pepper. On the other hand, the mixture of pine oil and copper hydroxide (4:1) also showed the strongest protective effect against pepper anthracnose among the 4 treatments tested; its disease incidence and disease control value were 49.8% and 41.7%, respectively. The other treatments showed low protective activities with control values of 7.4-17.1%. These results suggested that the mixture of pine oil and copper hydroxide (4:1) can be used for the environmental-friendly disease control of bacterial spot and anthracnose on pepper.

• Current Research on Agriculture and Life Sciences
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• v.23
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• pp.43-51
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• 2005

Pepper genetic resources consisting of introductions from Mexico and Nepal and susceptible and resistant controls were tested for resistance to gray leaf spot and to bacterial spot by serially inoculating the two disease pathogens, Stemphylium spp. first and Xanthomonas campestris pv. vesicatoria next, with application of fungicide after evaluation of resistance to gray leaf spot first. KC866, KC872, KC902, KC905 were resistant to gray leaf spot in addition to known resistance sources, KC43, KC47, KC220, KC319, KC320, KC380. KC897 was on the top of the resistance sources list, even better than KC177(163192), and was followed by KC889, KC896, KC898, all of which were introductions from Nepal.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.61.1-61
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• 1999

• Research in Plant Disease
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• v.21 no.4
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• pp.261-267
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• 2015

During the period from 2013 to 2014, disease occurrences by various pathogens in apple cultivars have been investigated in northern Gyeongbuk province of Korea. Anthracnose, white rot, Alternaria leaf spot, Marssonina blotch, and bacterial shoot blight as major diseases have been observed. Pathogens isolated from the symptomatic plants were identified as Colletotrichum gloeosporioides for anthracnose, Botryosphaeria dothidea for white rot, Alternaria alternata for Alternaria leaf spot, Marssonina mali for Marssonina blotch, and Pseudomonas syringae pv. syringae for bacterial shoot blight. Of all diseases, the bacterial shoot blight has been severely increased in chronically infested fields in Gyeongbuk province.

• Research in Plant Disease
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• v.29 no.4
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• pp.440-444
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• 2023

In August 2021, water-soaking symptoms of bacterial spot disease were observed on castor bean in a field in Gangseo District, Busan. Bacteria isolated from the lesion when cultured on tryptic soy agar appeared to be nonmucoid and pale green. To confirm whether the isolates were the causative agent of the spot disease, they were inoculated onto healthy castor bean plants. The same symptoms were observed on the inoculated tissue, and the bacteria were reisolated from the lesion. Furthermore, the isolates were consistent with the biochemical and physiological features of Pseudomonas capsici. Sequencing analysis using 16S rRNA and housekeeping genes (gyrB, rpoD) showed that the isolates shared a high sequence similarity with P. capsici. These results confirmed that the strains belonged to P. capsici. To our knowledge, this is the first report of bacterial spot disease caused by P. capsici on castor bean in Korea.