• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.209-213
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• 1986

Dominant aphid species and seasonal fluctuations of the colonizing aphids on apple tree, peach tree, and pear tree were examined without insecticide treatment during $1982{\sim}1984$ in Suweon. The dominant species among the colonizing aphids in each fruit tree were Myzus malisuctus in April-June and Aphis citricola in Aug.-Oct. on apple tree; Myzus persicae in early springtime and Hyalopterus pruni in May-Oct. on peach tree; Sappaphis piri in April-June, Oct. and Aphis citricola in July-Sept. on pear tree. M. malisuctus and A. citricola on apple tree showed 3 peaks a year; the former was early June, late Aug. and early Oct., the latter early June, middle Aug. and late Sept. M. persicae on peach tree showed peak on late May to early June, and H. pruni on middle June and middle Oct. S. piri and A. citricola on pear tree showed 2 peaks a year; the former was late May and late Oct., the latter early June and early Sept.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.249-258
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• 2019

The goal of this study was to isolate and characterize the wild yeast strains in the soils of Hajodae and Gyungpodae Beaches, Gyungpo Lake in Kangwon-do, Korea and evaluate their anti-demential and tyrosinase inhibitory activities. Among the 27 yeast strains isolated from 30 soil samples from Hajodae Beach, Cyberlindnera culbertsonii HJ31-1, Dothichiza pithyophila HJ22-4, Metschnikowia bicuspidata HJ16-1, and Sakaguchia cladiensis HJ14-1 were recorded for the first time in Korea. Additionally, six of the 55 wild yeast strains isolated from 45 soil samples from Gyungpodae Beach and Gyungpo Lake had not previously been detected in Korea, such as Aureobasidium melanogenum JR3-1. The microbiological characteristics and anti-demential and tyrosinase inhibitory activities of these previously unrecorded yeasts were investigated. Almost all of them were oval-shaped and had ascospores except for Dothichiza pithyophila HJ22-4, Diutina siamensis JR37-5, and Canadida gelsemii DC 35-1. Furthermore, they were all sugar-tolerant and able to grow in 20% glucose-containing YPD broth, except for Cyberlindnera culbertsonii HJ31-1. Diutina siamensis JR37-5 had the highest tyrosinase inhibitory activity (30.9%).

• Research in Plant Disease
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• v.29 no.2
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• pp.168-173
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• 2023

Agricultural antibiotics are widely used to inhibit the growth of phytopathogenic bacteria involved in plant diseases. However, continuous antibiotic overuse in crop production may lead to the development of antibiotic resistance in phytopathogenic bacteria. This study was conducted to evaluate the resistance to three different agricultural antibiotics (oxytetracycline+streptomycin, streptomycin, and validamycin A) in 91 strains of phytopathogenic bacteria including Pectobacterium carotovorum, Pseudomonas syringae pv. actinidiae, Clavibacter michiganensis subsp. michiganensis, C. michiganensis subsp. capsici, and Xanthomonas arboricola pv. pruni. Bacterial growth in the presence of various concentrations of validamycin A was also assessed spectrophotometrically by analyzing the optical density. All strains did not grow when the cells were exposed to oxytetracycline+streptomycin or 100× of streptomycin. However, among the 91 strains, 4% and 2% strains showed bacterial growth at the concentrations of 1× and 10× of streptomycin, respectively. Furthermore, 97%, 93%, and 73% strains were resistant to the 1×, 10×, and 100× of validamycin A, respectively, and especially, P. carotovorum contained the highest resistance to the validamycin A. Minimum bactericidal concentration values of validamycin A did not correlate with the patterns of agricultural antibiotic resistance. Further studies are needed to understand the incidence and development of antibiotic resistance in phytopathogenic bacteria.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.224-229
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• 1995

Occurrence and incidences of major diseases of peach (Prunus persicae pv. vulgaris), leaf curl caused by Taphrina deformans, bacterial shot hole caused by Xanthomonas campestris pv. pruni, brown rot caused by Monilinia fructicola, and anthracnose caused by Glomerella cingulata in peach orchards in Cheongdo and Kyungsan areas of Gyeongbuk province, Korea, were investigated for four years from 1990 to 1993. In leaf curl and bacterial shot hole which mainly occurred on leaves, frist disease occurrences were dated from late April to early May. The maximum leaf curl incidence was dated in mid May, while dates of the maximum bacterial shot hole incidence varied from mid May to mid August depending on the years surveyed. In brown rot and anthracnose on fruit, the first disease occurrence dates ranged from early June to early August; however, the maximum disease incidences for both were invariably dated in late August. The disease incidences on the dates of the maximum incidences differed year by year, and the averages for the 4 years were 13.2%, 10.5%, 10.9% and 3.8% for leaf curl, bacterial shot hole, brown rot and anthracnose, respectively. Especially in the leaf curl disease, the first disease occurrence dates and the maximum disease incidences matched with the amounts of precipitation of rain up to April, suggesting that the disease occurrence may be related to the precipitation during the early season. The occurrence of leaf curl was somewhat higher in cultivar“Baekmi”than other cultivars. All of the major disease occurred more in hilly orchards than in plain ones.

• The Journal of Internal Korean Medicine
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• v.16 no.1
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• pp.40-61
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• 1995

This study was performed to investigate concept, systoms, causes of disease, pathogenic mechanisms, therapies and precriptions about senile constipation through the successive medical literature, recent chinese medical literature and chinese medical joumals. Senile constipation seems to be applicable to dryness syndrom and constipation of insufficiency type, have something to do with kidney(the most), lung, spleen and large intestine. The most principal cause of disease is yin-fluid, the rest deficiency of qi, insufficiency of yang, stagnation of qi and retention of fever etc. There are enriching the blood and moistening dryness in principal therapy, the rest are invigorating qi and loosing the bowel, warming and invigorating the spleen and kidney, regulating the flow of qi and promoting the stagnancy of qi and expelling the pathogenic heat etc. In prescriptions there are Yunjangtang, Jengaektang, Hwanggitang, Jechunjeon, Yukmatang and Majainhwan as the causes of disease, meanwhile are Yungjang-tang, Jechunjeon and Majainhwan in the vulgaris prescriptions. And in medical herbs there are nourishing yin medicines as Rhizoma rehmanniac, Radix ophiopogonis and Radix scrophulariae etc., invigorating qi medicines as Radix astragali, Radix codonopsitis and Radix polygoni multiflori etc, invigorating yang medicines as Caulis cistanchis and Semen psoraleae etc., promoting qi circulating medicines as Radix saussurea, Lignum aquilariae and Radix linderae etc., and reducing fever and therapeutic method to keep the adverse qi flowing downward medicines as Semen cannabis, Rhizoma rhei, Fructus immaturus ponciri, and Cortex magnoliae etc.. Meantime Rhizoma rehmanniae, Radix ophiopogonis, Caulis cistanchis, Radix angelicae gigantis, Semen cannabis, Semen biotae, Semen pruni japonicae and Semen persicae in principal herb-medicines. In clinical reports the process of disease was between 10 to 20 years, the evacuation cycle between 4 to 7 days, generally possessed chronic diseases as hypertension, diabetes, arteriosclerosis and cerebro- vascular disorders etc. and the efficiency rate was more than 90%. The senile constipation is occured in succession or promoted by chronic diseases as obesity, hypertension, diabetes, arteriosclerosis. hrperlipemia, cerebro- vascular disorders etc., so diet-regulating, adequate exercise, proper evacuation-habit and psychologic rest etc. are important more than medicine-treatments.

• Research in Plant Disease
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• v.7 no.1
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• pp.37-41
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• 2001

This experiment was carried out to investigate the prevention of bacterial shot hole by Bordeaux mixture when it was sprayed on peach trees after harvest. bordeaux mixture was sprayed on \`Mibaeko\` peach trees 1 to 3 times after mid September, and the occurrence of bacterial shot hole was examined in the next year. Bacterial shot hole in leaves appeared from mid May and thereafter increased gradually. The more times was sprayed Bordeaux mixture, the less peaches were diseased with bacterial shot hole. At the beginning of August, the peach harvest time, the disease incidence of the untreated control plot was 27.4 to 38.1%, while the disease incidence was 9.7 to 31.8% when Bordeaux mixture was sprayed. The control value ranged from 16.5 to 64.6%. Occurrence of the fruit disease was similar to that of the leaf disease. Incidence of the fruit disease in the untreated control was 17.2 to 21.6%, but incase of the chemical treatment, it was 5.0 to 12.2 %, showing 41.9 to 70.9% of the control value. Chemical injury on peach leaves were not found in the 4-12 and 408 types, but occurred in some degrees in the 6-6 type of Bordeaux mixture.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1763-1772
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• 2017

This study aimed to isolate and characterize antibacterial metabolites from Pharbitis nil seeds and investigate their antibacterial activity against various plant pathogenic bacteria. The methanol extract of P. nil seeds showed the strongest activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibition concentration (MIC) value of $250{\mu}g/ml$. Among the three solvent layers obtained from the methanol extract of P. nil seeds, only the butanol layer displayed the activity with an MIC value of $125{\mu}g/ml$ against Xap. An antibacterial fraction was obtained from P. nil seeds by repeated column chromatography and identified as pharbitin, a crude resin glycoside, by instrumental analysis. The antibacterial activity of pharbitin was tested in vitro against 14 phytopathogenic bacteria, and it was found to inhibit Ralstonia solanacearum and four Xanthomonas species. The minimum inhibitory concentration values against the five bacteria were $125-500{\mu}g/ml$ for the n-butanol layer and $31.25-125{\mu}g/ml$ for pharbitin. In a detached peach leaf assay, it effectively suppressed the development of bacterial leaf spot, with a control value of 87.5% at $500{\mu}g/ml$. In addition, pharbitin strongly reduced the development of bacterial wilt on tomato seedlings by 97.4% at $250{\mu}g/ml$, 7 days after inoculation. These findings suggest that the crude extract of P. nil seeds can be used as an alternative biopesticide for the control of plant diseases caused by R. solanacearum and Xanthomonas spp. This is the first report on the antibacterial activity of pharbitin against phytopathogenic bacteria.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.106-112
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• 2015

This experiment was carried out to investigate the best spray timing for the control of the bacterial shot hole with Bordeaux mixture (6-6) after wintering in the peach orchard. We sprayed Bordeaux mixture (6-6) on 'Mibaekdo', 'Yumyeong' and 'Cheonhong' of peach verities from late-March to mid-April in 2001, 2002 and 2014, and examined how much bacterial shot hole and chemical injure occurred. The infection rate of bacterial shot hole according to spray time was 10.2 to 11.7% at leaves, and 1.7 to 2.2% at fruits in 2002. And Efficacy of the Bordeaux mixture treatment for control of bacterial shot hole at full blooming time 21.2 to 30.4% at leaves, 1.7 to 4.4% at fruits in 2014. The chemical injure occurred slightly for one week hence. The fruit bearing rate was 20.7 to 29.8% at 'Mibaekdo', and 35.4 to 61.9% at 'Yumyeong' peach trees. When the spray at the time of blooming period by bordeaux mixture was investigated the control effect of bacterial shot hole disease. The infected leaves was better than 21 to 25% twice the quantity of finished products and bordeaux self-preparation about 28 to 30% base quantity of finished products, also the control efficacy was higher in infected fruits trends in bordeaux self-preparation method and twice the quantity of finished products.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.912-916
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• 2014

Japanese apricot (Prunus mume Siebold and Zucc.) is a deciduous tree of the family Rosaceae, and it has long been used as a folk remedy for cough and dyspepsia. A new cultivar 'Okjoo' was developed from a cross between 'Gyokuei' and 'Rinsyu' carried out at the National Institute of Horticultural & Herbal Science in 1993. It w as s elected for good shape, large size and high yield capacity in 2006, and then it was granted official patent No. 4556 in 2013. It blooms 4 days and 2 days earlier than 'Gyokuei' and 'Rinsyu', respectively. Its flower petal color is pink, and the pollen amount is negligible. Its S-genotype, determined using Polymerase Chain Reaction with a S-RNase gene-specific primer pair, is $S_3S_6$. The average optimum harvest time of 'Okjoo' is late June. The fruit is round in shape and its suture is shallow. Average fruit weight is 18.5 g, and it contains total soluble solids $7.66^{\circ}Brix$ and titratable acidity at 4.81%. Fruit skin color is green. Sometimes only the light side of the fruits seems to develop blush. The incidence levels of scab (Cladosporium carpophilum Thumen) and bacterial shot hole (Xanthomonas arboricola pv. Pruni) are quite low. Consequently, 'Okjoo' seems to be a promising new cultivar for Japanese apricot growers.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.710-715
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• 2005

This research was to investigate inhibitory activity of Sasang medicines on Obesity. 56 kind of herb medicines to powder, abstract add 100 times methanol. Examine inhibitory effect against lipase activity in vitro. It was compared Xenical(Orlistat) with 56 kind of herb medicines. Inhibitory effect against lipase activity of Xenical as a standard was 93.3%. It is Inhibitory effect against lipase activity of Taeyangin herb medicine. (Fructus Pruni Tomentosae 77.7% Cortex Acanthopanacis73.5%, Fructus Chaenomelis73.1%, rice bran on a mallet head68.1%, Semen Fagopyri 48.1%, Radix Vitis 31.5%) It is Inhibitory effect against lipase activity of Soyangin herb medicine. (Radix Saposhnikoviae 91.5%, Semen Plantaginis 90.4%, Semen Trichosanthis 89.2%, Herba Schizonepetae 85.7%, Radix Euphorbiae Kansui 76.1%, Rhizoma Anemarrhenae 76.0%, Cortex Phellodendri 75.1%, Herba Menthae 74.8%, Radix Angelicae Pubescentis 61.2%, Rhizoma Alismatis 62.6%, Poria 60.9%, Rhizoma Notopterygii 22.5%, Radix Peucedani 18.2%, Caulis Akebiae 17.7%) It is Inhibitory effect against lipase activity of Taeeumin herb medicine. (Herba Spirodelae 91.4%, Radix Polygalae 88.3%, Arillus Longanae 84.3%, Radix Platycodi 81.7%, Semen Zizyphi Spinosae 80.2%, Spina Gleditsiae 79.7%, Herba Ephedrae 75.3%, Semen Raphani 73.1%, Rhizoma Cimicifugae 73.0%, Rhizoma Acori Graminei 71.8%, Flos Chrysanthemi71.0%, Radix et Rhizoma Rhei 68.4%, Vermiculus Holotrichia 59.9%, Radix Puerariae 55.3%, Fructus Schizandrae 53.4% Semen Coicis 50.6%, Semen Biotae 47.5%, Semen Nelumbinis 46.7%, Radix Angelicae Dahuricae 45.1%, Semen Castaneae 44.4%, Rhizoma Ligustici 34.5%, Tuber Liriopis 16.4%, Radix Scutellariae4.2%) It is Inhibitory effect against lipase activity of Soeumin herb medicine. (Pericarpium Arecae89.9%, Rhizoma Alpiniae Officinarum 89.5%, Radix Polygoni Multiflori81.2%, Rhizoma Cyperi 79.0%, Cortex Magnoliae 72.8%, Radix Aucklandiae 72.0%, Rhizoma Zingiberis 71.9%, Pericarpium Citri Reticulatae Viride 71.3%, Radix Cynanchi Wilfordi 57.7% Rhizoma Pinelliae 36.7%, Fructus Alpiniae Oxyphyllae 35.8% Fructus Aurantii Immaturus 17.5%, Pericarpium Citri 16.1%) Therefore, Radix Saposhnikoviae(91.5) and Herba Spirodelae(91.4%) were the most effective medicice of 56 kind of medicines.