• Research in Plant Disease
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• v.10 no.2
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• pp.94-99
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• 2004

'Shiranuhi' citrus cultivar bred by crossing 'Kiyomi' tangor and 'Nakano No.3' ponkan is cultivated in polyethylene film house, and the number of cultivating farmers is rapidly increasing in recent years. Recently, some diseases are taking place on 'Shiranuhi' fruit in some orchards, and were to be big problem in some case. It was surveyed that six diseases were mainly taken place in 'Shiranuhi' cultivating orchards in Jeju Island. They were Phytophthora citrophthora, Alternaria sp., Penicillium digitatum, Botrytis cinerea, Diaporthe citri and Xanthomonas axonopodis pv. citri.

• Research in Plant Disease
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• v.30 no.1
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• pp.78-81
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• 2024

This study aims to isolate and identify the fungal pathogen responsible for gummosis disease affecting Thanh Tra pomelo in Vietnam. Through molecular identification utilizing primer pairs ITS5 and ITS4, the analysis pinpointed Lasiodiplodia theobromae as the specific fungal pathogen. Notably, the fungal colonies exhibited vigorous growth on potato dextrose agar. Initially, these colonies appeared whitish-grey, transforming into a black-grey hue within 5-7 days at a temperature of 30℃. According to previous reports, Phytophthora spp. was the most common pathogenic genus causing gummosis on Thanh Tra pomelo in Vietnam. To our knowledge, this is the first report on L. theobromae causing gummosis on Thanh Tra pomelo in Vietnam.

• Research in Plant Disease
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• v.22 no.1
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• pp.1-8
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• 2016

Elsinoe fawcettii causing citrus scab was suppressed by rhizobacterial strains such as Burkholderia gladioli MRL408-3, TRH423-3 and Pseudomonas fluorescens THJ609-3, TRH415-2 having antifungal activity. The leaf surface of Satsuma mandarin, which was pre-treated with the rhizobacterial strains, was observed by a scanning electron microscope (SEM) after inoculation with E. fawcettii. The number of lesions was reduced on the leaves pre-treated with the rhizobacterial strains compared to those of untreated leaves. Especially, the lesions numbers was apparently reduced on the leaves pre-treated with B. gladioli MRL408-3. The observation by SEM revealed that not only the germination rate but also the length of germ tube of the pathogen were decreased on the rhizobacterial strains pre-treated leaves. These inhibition of the fungal growth was more strongly expressed on the leaves pre-treated with commercial fungicide imibenconazole, by which the lesions was rarely found on the leaves. Based on these results, it was suggested that rhizobacterial strains may inhibit the germination and growth of the E. fawcettii on the surface of citrus leaves, resulting in decrease of disease severity.

• Journal of fish pathology
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• v.23 no.3
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• pp.389-398
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• 2010

Effects of various concentration of yuzu Citrus junos Siebold ex Tanaka in the diets on growth, blood chemistry and disease resistance of olive flounder were determined. Fifteen hundred fish averaging 200~270g were fed on moist pellet containing yuzu at the concentrations of 0%(control), 2.5%, 5% and 7.5% for 3 months. After feeding trial, weight gain of fish fed 2.5% and 5.0% yuza diet was higher than those of fish fed 0% and 7.5% yuza diet but not significant(P>0.05). No differences in hematological and physiological indices of olive flounder were found among the experimental diets except for total cholesterol. Serum lysozyme activity was not significantly different among fish fed experimental diets but bactericidal activity of fish fed 7.5% yuza diet was significantly different from those of fish fed 0, 2.5 and 5% Yuza diets. Survival rates of fish fed 2.5% yuza diet at experimental infection with Edwardsiella tarda and Streptococcus sp. were higher than those of the other experimental groups but not significant. In conclusion, Dietary inclusion of 2.5~5% yuzu seems to have positive effects for fish health condition and disease resistance.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.370-375
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• 2009

Overproduction of peroxynitrite ($ONOO^-$) causes a variety of disease such as atherosclerosis, hypercholesterolemia, diabetes mellitus or obesity. Peroxynitrite scavenging activities and HPLC analysis on the five Oriental medicinal drugs belonging to the genus Citrus, Aurantium or Poncirus (Rutaceae family) and HPLC analysis were taken to evaluate flavanone glycosides with peroxynitrite scavenging activity. The $IC_{50}s$ of the five crude drugs were shown as follows: Aurantii nobilis Pericarpium (Jinpi, 18.3 ${\mu}g$/ml), Citrii unshiu Pericarpium (Chungpi, 7.50${\mu}g$/ml), Citrii unshiu Semen (Gyulhaek, >50.0${\mu}g$/ml), Aurantii Fructus (Jigak, 18.3${\mu}g$/ml), and Poncirii Fructus (Jisil, >50.0${\mu}g$/ml) where Korean crude drug's names are noted in the parenthesis. Peroxynitrite scavenging effect of flavanones or their glycosides usually contained in Citrus species were observed as follows: hesperetin (1.89 ${\mu}g$/ml), naringenin (7.77 ${\mu}g$/ml), hesperidin (8.44 ${\mu}g$/ml), poncirin (>50.0 ${\mu}g$/ml)and ponciretin(>50.0 ${\mu}g$/ml). The activities of naringin and poncirin with ${\alpha}$-L-rhamnopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranosyl moiety were weak. HPLC analytical data revealed that Jinpi (the peels of mature fruits of Citrus unshiu) and Chungpi (the peels of immature fruits of C. unshiu) had high quantities of hesperidin as the value of 142.1${\pm}$0.21 and 104.51${\pm}$1.10 mg/g dried weight, respectively. Poncirin was clearly detected in only Jisil and naringenin and naringin were not observed on the HPLC chromatogram of the five crude drugs.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.644-653
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• 2019

The genetic variability of 'Candidatus Liberibacter asiaticus' (CLas) population associated with huanglongbing (HLB) disease of citrus in North Eastern (NE) region of India, a geographically locked region, and home for the diversity of many citrus species was analyzed on the basis of tandem repeat numbers (TRN) in variable CLIBASIA_01645 genomic loci. Fifty-five CLas strains sampled from different groves of NE Hill (NEH) region of India were in single amplicon group, but there was remarkable genetic variability in TRNs. The TRN in HLB-associated CLas strains varied from 0-21 and two novel repeat motifs were also identified. Among the NE population of CLas, TRN5 and TRN9 were most frequent (total frequency of 36.36%) followed by TRN4 (14.55%) and TRN6, TNR7 with a frequency of 12.73% each. Class II type CLas genotypes (5 < TRN ≤ 10) had highest prevalence (frequency of 60.00%) in the samples characterized in present study. Class I (TRN ≤ 5) genotypes were second highest prevalent (29.09%) in the NEH region. Further analysis of genetic diversity parameters using Nei's measure (H value) indicated wide genetic diversity in the CLas strains of NE India (H value of 0.58-0.86). Manipur CLas strains had highest genetic variability (0.86) as compared to Eastern, Southern and Central India. The R₁₀ values (TRN ≤ 10/TRN > 10) of NE CLas population was 10.43 (73/7), higher from other regions of India. Present study conclusively reported the occurrence of high genetic variability in TRN of CLas population in North East Indian citrus groves which have evolved to adapt to the specific ecological niche.

• Research in Plant Disease
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• v.17 no.1
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• pp.78-81
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• 2011

Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on potato dextrose agar was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangiophores were $6{\sim}20\;{\mu}m$ in diameter. Sporangia were globose and $40{\sim}200\;{\mu}m$ in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and $4{\sim}10\;{\mu}m$ in size. Columella were globose to sub-globose and $85{\sim}120\;{\mu}m$ in size. On the basis of mycological characteristics, pathogenicity test, and the ITS sequence analysis, the causal fungus was identified as Rhizopus oryzae. To our knowledge, this is the first report of soft rot caused by R. oryzae on unshiu orange in Korea.

• Research in Plant Disease
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• v.11 no.1
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• pp.10-15
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• 2005

The occurrence of melanose was investigated on yuzu at Goheung and Boseong in Jeonnam province in 1997 and 1998 seasons. The disease occurrence on leaf was initiated from late May in 1997 and early May in 1998, severest in late of June on leaf, and in case of fruit, initiated from early July in 1997 and late June in 1998 with a peak in early August. The disease was occurred in twenty days more earlier in 1998 season than 1997 season. We think this was caused by temperatures during April and May. And it was supposed that the disease severity on the severest late of June was closely related to the rainfall and relative humidity during June. The disease severity was severer in old tree than the young.

• 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.

• Journal of the Korean Society of Food Culture
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• v.16 no.5
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• pp.515-524
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• 2001

Differences in dietary intake of Korean Americans (KA) by the length of residence in the U.S. were studied in relation to health and disease patterns in Michigan. Of 1860 questionnaires mailed, 637 (34.3%) responded with demographics, anthropometrics, self-reported disease patterns, lifestyle, and dietary patterns (93-item FFQ developed for KA). Complete responses were available for 498 people (263 men,253 women, aged 30-87 yr), who were then divided into three groups based on the number of years lived in the U.S.: 15y, 16-25y, 26y. Age-adjusted weight, height, BMI, and waist to hip ratio were within the normal ranges and did not differ among the three groups. Chronic diseases frequently reported in men and women (age-adjusted) included hypertension (14.4%, 14.1%), digestive diseases (5.4%, 8.5%), diabetes (3.6%,4.9%), and arthritis(3.3%, 12.5%), respectively. The length of residence in the U.S. was inversely associated with the age-adjusted prevalence of digestive diseases (12.4%, 6.5%, 0.4% in men, 13.0%, 11.7%, 0% in women). The length of residence was positively associated with health consciousness, receiving regular health care, taking supplements regularly, and exercising, while inversely related to smoking. The majority favored American foods for breakfast and Korean foods for dinner. Foods frequently consumed included cooked rice (w/other grains). kimchi, coffee (w/cream and sugar),bread (white and dark), citrus juice, milk (low fat and skim), lettuce and cucumber, apple, seaweed, and soda. Intake frequency of the Korean starch food group was inversely associated with the length of residence for both men and women (p<0.001), but not with the American starch food group. Fat intake did not differ by the length of residence in the U.S. The dietary changes were associated with the length of residence and chronic disease patterns for the first generation of KA, which should be further examined 'for the subsequent generation of KA.