• Research in Plant Disease
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• v.27 no.4
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• pp.172-179
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• 2021

This study aimed to assess the disease incidence and distribution of toxigenic in Korean triticale. The pathogen of triticale that cause Fusarium head blight were isolated from five different triticale cultivars that cultivated in Suwon Korea at 2021 year. The 72 candidate were classified as a Fusarium asiaticum by morphology analysis and by ITS1, TEF-1α gene sequence analysis. And the results of pathogenicity with 72 isolates on seedling triticale, 71 isolates were showed disease symptom. Also, seven out of 71 Fusarium isolates were inoculated on the wheat, to test the pathogenicity on the different host. The results showed more low pathogenicity on the wheat than triticale. The results of analysis of toxin type with 72 isolates, 64.6% isolates were produced nivalenol type toxin and other 4.6% and 30.8% isolates were produce 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol, respectively. To select fungicide for control, the 72 Fusarium isolates were cultivated on the media that containing four kinds fungicide. The captan, hexaconazole, and difenoconazole·propiconazole treated Fusarium isolates were not showed resistance response against each fungicide. However, six isolates out of 72 isolates, showed resistance response to fludioxonil. This study is first report that F. asiaticum causes Fusarium head blight disease of triticale in Korea.

• Research in Plant Disease
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• v.29 no.3
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• pp.276-285
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• 2023

This work investigated the viral infection in jujube plants in Korea. A total of 61 samples with the symptoms of putative viral infection were collected from experimental fields and orchards. Thereafter, the samples were subjected to metatranscriptome analysis, Reverse transcription polymerase chain reaction analysis, and nucleotide sequence analysis. These analyses identified the presence of two DNA viruses, jujube-associated badnavirus (JuBV), jujube mosaic-associated virus (JuMaV), and one RNA virus, jujube yellow mottle-associated virus (JYMaV). All samples collected were confirmed to be infected by at least one of the three viruses, with most showed multiple infections. The detection rates of JuBV, JYMaV, and JuMaV were 100%, 90.2%, and 8.2%, respectively. Only three combinations of viral infections were found: 9.8% of samples showed single infection of JuBV, 82.0% showed double infection of JuBV+JYMaV, and 8.2% showed triple infection of JuBV+JYMaV+JuMaV. Sequence analysis of the three viruses showed very high homology with respective virus isolates reported in China. This study is predicted to provide fundamental data to produce virus-free jujube seedlings and represents the first report of JuBV and JuMaV infection in Korea.

• Research in Plant Disease
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• v.29 no.1
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• pp.23-38
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• 2023

The fire blight caused by Erwinia amylovora (Ea) is a devastating disease of Rosaceae plants, including commercially important apple and pear trees. Since the first report in Korea in May 2015, it has been spreading to neighboring regions gradually. Host plants can be infected by pollinators like bees, rainfall accompanied by wind, and cultural practices such as pruning. Many studies have revealed that wild Rosaceae plants such as Cotoneaster spp., Crataegus spp., Pyracantha spp., Prunus spp., and Sorbus spp. can be reservoirs of Ea in nature. However, wild Rosaceae plants in Korea have not been examined yet whether they are susceptible to fire blight. Therefore, the susceptibility to fire blight was examined with 25 species in 10 genera of wild Rosaceae plants, which were collected during 2020-2022, by artificial inoculation. Bacterial suspension (10⁸ cfu/ml) of Ea type strain TS3128 was inoculated artificially in flowers, leaves, stems, and fruits of each plant species, and development of disease symptoms were monitored. Moreover, the presence of Ea bacteria from inoculated samples were checked by conventional polymerase chain reaction. Total 14 species of wild Rosaceae plants showed disease symptoms of fire blight, and Ea bacteria were detected inside of inoculated plant parts. These results suggest that wild Rosaceae plants growing nearby commercial apple and pear orchards in Korea can be Ea reservoirs, and thus they should be monitored regularly to minimize the damage by Ea infection and spreading.

• Research in Plant Disease
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• v.28 no.4
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• pp.237-244
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• 2022

Chrysanthemum plants are one of the most economically important plants in South Korea. Both virus and viroid can cause diseases and economic damage to the plants. In this study, we investigated the detection of seven viruses and two viroids in 350 chrysanthemum plants cultivated in Yesan-gun, Chungcheongnam-do. Two viruses, chrysanthemum virus B (CVB) and tomato aspermy virus (TAV), and two viroids, chrysanthemum chlorotic mottle viroid (CChMVd) and chrysanthemum stunt viroid (CSVd), were detected in this study. The two viruses were detected in six samples and one sample, respectively. The two viroids were detected in 97 samples and 21 samples, respectively. The nucleotide sequences of the CVB-CN-Y, TAV-CN-Y, CChMVd-CN-Y, and CSVd-CN-Y obtained in this study showed 83.7-86.9%, 99.2-100.0%, 94.4-99.5%, and 95.7-99.7% identity, respectively, compared to their other strains/isolates. The CVB-CN-Y and TAV-CN-Y showed the greatest nucleotide sequence homology to CVB-GS1 and three TAV isolates (TAV-V, TAV-P, and TAV-ChJ), respectively. The CChMVd-CN-Y and CSVd-CN-Y showed the greatest nucleotide sequence homology to CChMVd-Horst and four CSVd isolates (Au1.1, K4pop, Sagae, and Tochigi), respectively. This study is the report on the infection rate of viruses and viroids in chrysanthemum plants cultivated in Yesan-gun in 2021.

• Research in Plant Disease
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• v.30 no.1
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• pp.26-33
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• 2024

In 2023, symptoms like damping-off disease were observed in 74 paprika growing in greenhouses in Cheorwon-gun, Gangwon-do, Korea. In this study, we tried to find the cause of the damping-off disease outbreak. We collected symptomatic seedlings and observed the typical crescent-shaped conidia of Fusarium oxysporum by microscope. To confirm the presence of F. oxysporum in the samples, polymerase chain reaction was performed using primers specific for F. oxysporum; the resulting sequence showed 99.11% identity with F. oxysporum. To confirm the pathogenicity of the F. oxysporum (CW) isolated from the samples, healthy paprika plants were inoculated with F. oxysporum CW and damping-off symptoms were observed 2 weeks later. To investigate whether the damping-off disease outbreak in Cheorwon-gun was caused by F. oxysporum-contaminated seeds, 100 paprika seeds were disinfected and placed in Murashige and Skoog medium. Typical pink F. oxysporum hyphae were found only in control non-disinfected seeds. An 18S rRNA-based and a TEF genebased phylogenetic analysis showed that the F. oxysporum CW isolate was not grouped with a F. oxysporum isolate reported from Cheorwon-gun in 2019. This study is the first report that an outbreak of damping-off disease in paprika in Cheorwon-gun, Gangwon-do, Korea, was caused by contamination of F. oxysporum seeds.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.310-322
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• 2000

Background : Phospholipase C(PLC) plays an important role in cellular signal transduction and is thought to be critical in cellular growth, differentiation and transformation of certain malignancies. Two second messengers produced from the enzymatic action of PLC are diacylglycerol (DAG) and inositol 1, 4, 5-trisphosphate (IP3). These two second messengers are important in down stream signal activation of protein kinase C and intracellular calcium elevation. In addition, functional domains of the PLC isozymes, such as Src homology 2 (SH2) domain, Src homology 3 (SH3) domain, and pleckstrin homology (PH) domain play crucial roles in protein translocation, lipid membrane modificailon and intracellular memrane trafficking which occur during various mitogenic processes. We have previously reported the presence of PLC-${\gamma}1$, ${\gamma}2$, ${\beta}1$, ${\beta}3$, and ${\delta}1$ isozymes in normal human lung tissue and tyrosine-kinase-independent activation of phospholipase C-${\gamma}$ isozymes by tau protein and AHNAK. We had also found that the expression of AHNAK protein was markedly increased in various mstologic types of lung can∞r tissues as compared to the normallungs. However, the report concerning expression of various PLC isozymes in lung canærs and other lung diseases is lacking. Therefore, in this study we examined the expression of PLC isozymes in the paired surgical specimens taken from lung cancer patients. Methods : Surgically resected lung cancer tissue samples taken from thirty seven patients and their paired normal control lungs from the same patients, The expression of various PLC isozymes were studied. Western blot analysis of the tissue extracts for the PLC isozymes and immunohistochemistry was performed on typical samples for localization of the isozyme. Results : In 16 of 18 squamous cell carcinomas, the expression of PLC-${\gamma}1$ was increased. PLC-${\gamma}1$ was also found to be increased in all of 15 adenocarcinoma patients. In most of the non-small cell lung cancer tissues we had examined, expression of PLC-${\delta}1$ was decreased. However, the expression of PLC-${\delta}1$ was markedly increased in 3 adenocarcinomas and 3 squamous carcinomas. Although the numbers were small, in all 4 cases of small cell lung cancer tissues, the expression of PLC-${\delta}1$ was nearly absent. Conclusion : We found increased expression of PLC-${\gamma}1$ isozyme in lung cancer tissues. Results of this study, taken together with our earlier findings of AHNAK protein-a putative PLD-${\gamma}$, activator-over-expression, and the changes observed in PLC-${\delta}1$ in primary human lung cancers may provide a possible insight into the derranged calcium-inositol signaling pathways leading to the lung malignancies.

• Radiation Oncology Journal
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• v.18 no.1
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• pp.32-39
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• 2000

Purpose :The incidence of adenocarcinoma of the uterine cervix is low. Traditionally, Low Dose Rate (LDR) brachytherapy has been used as a standard modality in the treatment for patients with carcinoma of the uterine cervix. The purpose of this report is to evaluate the effects of the High dose rate (HDR) brachytherapy in the patients with adenocarcinoma of the uterine cervix compared with the LDR. : From January 1971 to December 1992, 106 patients of adenocarcinoma of uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University with curative intent. LDR brachytherapy was carried out on 35 patients and 71 patients were treated with HDR brachytherapy. In LDR Group, 8 patients were in stage I, 18 in stage II and 9 in stage III. External radiation therapy was delivered with 10 MV X-ray, daily 2 Gy fractionation, total dose 40$\~$46Gy (median 48 Gy). And LDR Radium intracavitary irradiation was peformed with Henschke applicator, 22$\~$59 Gy to point A (median 43 Gy). In HDR Group, there were 16 patients in stage 1, 38 in stage II and 17 in stage III. The total dose of external radiation was 40$\~$61 Gy(median 45 Gy), daily 1.8$\~$2.0 Gy. HDR Co-60 intracavitary irradiation was peformed with RALS (Remote Afterloading System), 30 $\~$ 57 Gy(median 39 Gy) to point A, 3 times a week, 3 Gy per fraction. Conclusion : The 5-year overall survival rate in LDR Group was 72.9$\%$, 61.9$\%$, 45.0$\%$ in stage I, II, III, respectively and corresponding figures for HDR were 87.1$\%$, 58.3$\%$, 41.2$\%$, respectively (p>0.05). There was no statistical difference in terms of the 5-year overall survival rate between HDR Group and LDR Group in adenocarcinoma of the uterine cervix. There was 11$\%$ of late complication rates in LDR Group and 27$\%$ in HDR Group. There were no prognostic factors compared HDR with LDR group. The incidence of the late complication rate in HDR Group stage II, III was higher than that in LDR Group(16.7$\%$ vs. 31.6$\%$ in stage II, 11.1$\%$ vs. 35.3$\%$ In stage III, p>0.05). Although the incidence of radiation induced late complication rate was higher in HDR Group stage II and III patients than that in the LDR Group, statistical significance was not detected and within acceptable level. Conclusion : There was no difference in terms of 5-year survival rate and failure pattern in the patients with adenocarcinoma of the uterine cervix treated with HDR and LDR brachytherapy. Even late complication rates were higher in the HDR group It was an acceptable range. This retrospective study suggests that HDR brachytherapy seems to replace the LDR brachytherapy in the adenocarcinoma of the uterine cervix. However, further studies will be required to refine the dose rate effects.