• Research in Plant Disease
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• v.24 no.4
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• pp.348-352
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• 2018

A multiplex reverse transcription-polymerase chain reaction (mRT-PCR) assay was developed for the detection of Clover yellow vein virus (ClYVV), Peanut mottle virus (PeMoV), and Tomato spotted wilt virus (TSWV), which were recently reported to infect soybean and azuki bean in Korea. Species-specific primer sets were designed for the detection of each virus, and their specificity and sensitivity were tested using mixed primer sets. From among the designed primer sets, two combinations were selected and further evaluated to estimate the detection limits of uniplex, duplex, and multiplex RT-PCR. The multiplex RT-PCR assay could be a useful tool for the field survey of plant viruses and the rapid detection of ClYVV, PeMoV, and TSWV in leguminous plants.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.737-741
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• 2007

Typical phytoplasma witches' broom symptoms were observed in black locust (Robinia pseudoacacia L.) in Korea. The symptoms of the disease were showing abnormally small leaves, shortened intemodes and proliferation of shoots. The phytoplasmas were detected consistently in all the symptomatic samples by the amplification with phytoplasma universal primer pairs P1/P7 and R16F2n/R2, and the expected size was 1.8 kb and 1.2 kb. However, the phytoplasma DNA was not detected in healthy seedling. Based on sequence analysis of amplified region, this phytoplasma has close homologies with aster yellow, mulberry dwarf, maize bushy stunt, ash witches' broom and sumac witches' broom phytoplasmas, more than 99.2% but showed homologies with black locust witches' broom (GeneBank Accession No. AF 244363), and jujube witches' broom, 88.6% and 87.7%, respectively. This phylogetic analysis indicates that the black locust witches' broom phytoplasma founded in korea should be classified in the Candidatus phytoplasma asteris (16Sr I) group and clearly distinct from the black locust witches' broom group 16Sr III (peach X-disease phytoplasma group).

• Research in Plant Disease
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• v.23 no.1
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• pp.1-18
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• 2017

Pseudomonas syringae pv. actinidiae, the causal agent of bacterial canker, is currently causing severe economic losses to kiwifruit production worldwide. The pathogen has affected green-fleshed kiwifruit cutlivars and yellow-fleshed kiwifruit cultivars since 1988 and 2006 in Korea, respectively. In recent years, the biovar 3 strains of P. syringae pv. actinidiae were introduced through imported contaminated pollens and have rapidly spread to neighboring kiwiruit orchards by secondary infection, leading to outbreaks of bacterial canker and tremendous damages on yellow- and red-fleshed kiwifruit cultivars. In this review, we summarize the various management practices of bacterial canker of kiwifruit such as disease escaping, cultural practices, blocking of dissemination, early diagnosis, eradication of inoculum sources, chemical control, and trunk injection on the basis of our research works and field experiences and important research products conducted during the last three decades in the world. Finally, we propose a manual for the efficient management of the disease that can be practically utilized at the farmers' orchards in order to keep kiwifruit vines healthy in the future.

• Journal of Acupuncture Research
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• v.25 no.5
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• pp.1-16
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• 2008

Backgrounds : There have not been so many studies about the correlation of logical background between acupuncture and herbal medicine. Objectives : This study was aimed to find out the logical relationship between acupuncture points of Wushijiuyu(五十九兪) and Fangfengtongshengsan(防風通聖散) for the treatment of fever disease. Methods : I investigated the background of rationale of Wushijiuyu(五十九兪) and Fangfengtongshengsan(防風通聖散) through survey of classical text include Yellow Emperor's Classic of Medicine(.帝.經內經, Hwang Di Nei Jing), Liujing(類經), Zhenjiujiayijing(鍼灸甲乙經) and Huangdisuwenxuanmingfanglun(黃帝素問宣明方論). Results & Conclusions : The words "Wushijiuyu(五十九兪) and Wushijiuci(五十九刺)" are founded in the Yellow Emperor's Classic of Medicine(黃帝內經) are either prescription of the acupuncture points for the treatment of fever disease. However, acupuncture points of two methods are not same. According to Liujing(類經), Wushijiuyu(五十九兪) have used acupuncture points located in head, upper and lower extremities, trunk, and back. However Wushijiuci(五十九刺) just select acupuncture points of head and extremities without those of trunk and back. Acupuncture points located in yang meridian(45points) and Dumai(督脈, 5points) are significantly used more than those of yin meridian(8 points) and Renmai(任脈, 2points) in Wushijiuyu(五十九兪) and Wushijiuci(五十九刺). The distribution of acupuncture points used Wushijiuyu(五十九兪) have closer correlation with Fangfengtongshengsan(防風通聖散) than Wushijiuci(五十九刺) in the prescription.

• Research in Plant Disease
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• v.17 no.3
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• pp.265-271
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• 2011

Seven phytoplasma diseases have been occurred on floricultural crops in Korea : Ph-ch1 and Ph-ch2 of chrysanthemum, Ph-lily of lily, petunia flat stem-Korean (PFS-K) of petunia, poinsettia branch inducing- Korean (PoiBI-K) of poinsettia, statis witches' broom-Korean (SWB-K) of statis and azalea witches broom (AWB). Classification of the seven phytoplasmal diseases based on 16S ribosomal RNA (rRNA) sequences showed that floricultural crop phytoplasma disease were widespread in order of aster yellow (AY), stolbur and X-disease in Korea. In phenotypic characters, the fasciation was occurred in both monocotyledon plant of lily and dicotyledon plants of petunia and poinsettia. Besides, the fascination was occurred in Ph-lily of stolbur, petunia PFS-K of AY and PoiBI-K of X-disease. This result indicated that phytoplasma classification based on 16S rRNA and symptoms are not consistently related. The comparison of 16S rRNA sequence of the seven floricultural crop phytoplasma with five tree phytoplasmal diseases of jujube witches' broom, paulownia witches' broom, wild jujube witches' broom, mulberry dwarf, golden rain phytoplasma occurred in Korea showed as high as 88.5-99.9% homology. Among them, especially mulberry dwarf showed the highest homology with the seven floricultural crop phytoplasms. Based on this result, floricultural crop phytoplasmas were assumed to be transmitted by insect vectors from tree phytoplasmas in Korea.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.243-248
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• 2011

This investigation was conducted to develop an integrated disease management system against large patch disease occurred in a golf course. Large patch, brown patch, and Rhizoctonia blight sometimes are used interchangeably by turfgrass managers and researchers, Large patch disease of zoysiagrass is caused by a soilborne fungus called Rhizoctonia solani. Although this fungus is very similar to the one that causes brown patch disease of cool-season turfgrasses in mid-summer. Large patch development is favored by high thatch and soil moisture. Avoid overwatering the turfgrass, especially in the fall or early spring. Poorly-drained areas are very susceptible to injury from large patch and should be reconstructed (draining tiles, etc) to avoid soil saturation. However, control of yellow patch with fungicides is normally not recommended because the disease has only cosmetic effects and symptoms are usually very short-lived. Therefore, we reviewed the symptom of large patch to look for control method by soil management method.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.190-195
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• 1994

Studies were conducted to determine the potential of sodium hypochlorite(SHC) on the control of bacterial yellow blotch in cultivated oyster mushroom, Pleurotus ostreatus. SHC at the concentration of 80 ppm was effective on the control of Pseudomonas agarici causing yellow blotch in oyster mushroom except number 916 isolate. In vitro the mycelial growth was slightly inhibited at the concentration higher than 100 ppm of sodium hypochlorite, but retardation of the mycelial growth was soon recovered. Spray of SHC solution at the concentration of 40-50 ppm per day significantly reduced the incidence of the yellow blotch without impairing the growth of oyster mushroom in field culture. However, the higher concentration of SHC(67 ppm) induced yellow brown or dark gray in color and deformed cap and elongated stripe in morphology of fruiting body. Results indicate that periodical spray of sodium hypochlorite seems to be the recommendable method for protection against bacterial yellow blotch disease in oyster mushroom without reducing food quality.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.836-842
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• 2004

An experiment was conducted to study the performance of broilers chicks (2 to 42 d of age) fed diets containing pearl millet (PM, Pennisetum typhoides), foxtail millet (FOM, Setaria italica) or finger millet (FIM, Elusine coracana) totally replacing (w/w) yellow maize (YM) with and with out supplementing non-starch polysaccharide (NSP) hydrolysing enzymes at the rate of 0.5 g/kg diet. Enzyme preparation contained amylase 2,400 units, hemi-cellulase 5,400 units, cellulase 12,000 units, protease 2,400 units and beta-glucanase 106 units/g. Each diet was fed to eight replicates (five female Vencob broilers/replicate) housed in stainless steel battery brooders. The estimated metabolizable energy (ME) contents of YM, PM, FOM and FIM were FM (PM) were about 3,389, 2,736, 3,303 and 2,846 kcal/kg, respectively. Total replacement of YM with FOM did not influence the body weight gain, ready to cook yield, relative weights of giblet, liver, intestine, lymphoid organs (bursa and spleen) and length of intestine, antibody titers and livability at 42 d of age. But the food efficiency decreased significantly in FOM fed broilers compared those fed YM. Further, the fat content in thigh muscle reduced with FOM fed groups compared to those fed YM. The performance of broilers decreased significantly in PM and FIM fed broilers compared to those fed YM. The relative weights of giblet, gizzard and liver increased in FIM fed groups compared to those fed YM as the principal source of energy in broilers. Incorporation of NSP hydrolysing enzymes in commercial broiler diets improved the efficiency of feed utilization during starter phase but not at 42 d of age. The results thus indicate that yellow maize can be replaced in toto on weight basis in commercial broiler diets without affecting the performance. Supplementation of NSP hydrolysing enzymes was beneficial in enhancing feed utilization during the starter phase.

• Research in Plant Disease
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• v.19 no.2
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• pp.77-83
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• 2013

Bean yellow mosaic virus (BYMV; genus Potyvirus, family Potyviridae) causes severe losses to various legume species and a number of non-legume species, particularly freesia plants. In a survey of virus diseases in Gyeonggi province, Korea, BYMV isolates were identified from many cultivated freesia species. Here, we determined the complete nucleotide sequences of a BYMV freesia isolate (BYMV-Fr; accession number FJ492961). BYMV-Fr genome consists of 9,545 nucleotides (nt) excluding the poly (A) tail and encodes 3,057 amino acid (aa), with an AUG start and UAG stop codon, containing one open reading frame typical of a potyvirus polyprotein. The polyprotein of BYMV-Fr was divided to ten proteins and the cleavage sites of each protein were determined. The coat protein (CP) and polyprotein of BYMV-Fr were compared at the aa level with those of the previously reported 4 BYMV isolates. BYMV-Fr shared 90.1 to 97.1 and 91.0 to 92.5% at the CP and polyprotein homology. Interestingly, BYMV-Fr showed identities of a lower level at the nt level of 5' noncoding region (61.4 to 67.6%) and at the aa level of P1 (71.4 to 72.8%), comparing with four BYMV isolates. Based on the aa sequence diversity of CP and polyprotein, phylogenetic analysis with the four BYMV isolates showed two distinct groups and BYMV-Fr and most BYMV isolates were most closely related to the clover yellow vein virus among 52 potyviruses. To our knowledge, this is the first report of the complete genome sequence of BYMV freesia strain.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.125-138
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• 2024

Citrus yellow vein clearing virus (CYVCV) is a member of the Alphaflexiviridae family that causes yellow vein clearing symptoms on citrus leaves. A total of 118 leaf samples from nine regions of six provinces in Korea were collected from various citrus species in 2020 and 2021. Viral diagnosis using next-generation sequencing and reverse transcription polymerase chain reaction (RT-PCR) identified four viruses: citrus tristeza virus, citrus leaf blotch virus, citrus vein enation virus, and CYVCV. A CYVCV incidence of 9.3% was observed in six host plants, including calamansi, kumquat, Persian lime, and Eureka lemon. Among the citrus infected by CYVCV, only three samples showed a single infection; the other showed a mixed infection with other viruses. Eureka lemon and Persian lime exhibited yellow vein clearing, leaf distortion, and water-soak symptom underside of the leaves, while the other hosts showed only yellowing symptoms on the leaves. The complete genome sequences were obtained from five CYVCV isolates. Comparison of the isolates reported from the different geographical regions and hosts revealed the high sequence identity (95.2% to 98.8%). Phylogenetic analysis indicated that all the five isolates from Korea were clustered into same clade but were not distinctly apart from isolates from China, Pakistan, India, and Türkiye. To develop an efficient diagnosis system for the four viruses, a simultaneous detection method was constructed using multiplex RT-PCR. Sensitivity evaluation, simplex RT-PCR, and stability testing were conducted to verify the multiplex RT-PCR system developed in this study. This information will be useful for developing effective disease management strategies for citrus growers in Korea.