• Korean journal of applied entomology
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• v.38 no.2
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• pp.85-91
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• 1999

Torymus sinensis was found to be a solitary ectoparasitoid attacking the larvae ofDryocosmus kuriphilus. The sex ratio of Torymus sinensis was close to 1 : 1 in foreign chestnut varieties.Under constant temperatures of 15"C, 20$^{\circ}$C, and 25"C, the preoviposition period and longevity of theadult was longer at lower temperatures when fed on honey. Most of the Torymus sinensis female havemature eggs in their ovaries just after emergence. The number of mature eggs reached to average 22.5individuals per female in four days, which was the highest value, after the emergence and then decreasedgradually. Eggs were laid on the larvae of the host or attached on inner surface of the gall chamber. Theeggs were oval in shape, measuring 0.49 mm length and 0.13 mm width and the color of the justoviposited egg was milky white. The larvae appeared in one day after being deposited at 20$^{\circ}$C. Thepupae, 2.25 mm length for female and 1.89 mm length for male, was milky white in color just afterpupation but became black later. In Kangwon Province, development period of chestnut galls formated byDryocosmus kuriphilus were mid April to late May and its primary parasitoid, Torymus sinensis adult,emerged from withered previous year galls in early April to early May. This species has one generation ina year, and hibernated with the matured larvae. hibernated with the matured larvae.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.201-205
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• 2016

In August 2015, leaf spot symptoms were observed on Korean gondre thistle (Cirsium setidens) in Youngwol, Korea. During the early stage, the symptoms appeared as one or more small gray-brown to brown spots on plant leaves. The spots showed extensive enlargement over time and eventually became large dark brown to black lesions on the whole leaf. Stemphylium species were consistently isolated from affected leaves. All isolates were identified as S. lycopersici, S. solani, or S. xanthosomatis based on morphological and cultural characteristics. The isolates were confirmed as S. lycopersici based on a multilocus sequence analysis using the ribosomal internal transcribed spacer (ITS) region, elongation factor 1, GAPDH (glyceraldehyde-3-phosphate dehydrogenase), and the noncoding region between the vacuolar membrane ATPase catalytic subunit A gene and a gene involved in vacuolar biogenesis. Pathogenicity was tested by spore suspension inoculation on wounded or unwounded gondre leaves. The lesions were observed on inoculated leaves within 3 days after inoculation, regardless of wound. To our knowledge, this is the first report of the leaf spot on gondre thistle caused by S. lycopersici in Korea or elsewhere.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.7-13
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• 1982

Habit characteristics of imperfect and perfect stage of D. bryoniae encountered on naturally infected seeds of cucumber and pumpkin were studied by the blotter method and compared with those grown on Difco potato dextrose agar (PDA), V-8 juice agar and water agar leaf medium (WALM). Most of the pycnidiospores obtained from each isolate of this fungus grown on PDA were non-septate and microtype. Non-septate pycnidiospores were predominanted in all isolates, but a macrotype of the non-septate and a number of uniseptate pycnidiospores were produced on V-8 juice agar and water agar leaf medium. On seed the pycnidiospores were mostly non -septate, but rarely uniseptate ones were also found. On radicle of cucumber seed, the pycnidiospores were non-septate and uniseptate but small percentage biseptate with somewhat constricted at septa. Pycnidiospores produced on V-8 juice agar and water agar leaf medium were similar to those produced on seeds. In the present investigation the perithecia were mostly globose to subglobose with apical papillate ostiole and whitish spore masses formed on the ostiole of perithecia, either on naturally infected seed or on culture media. The mature perithecia were dark brown to black. They were partially embedded or erumpent on seed coat and culture media. The perithecia varied in size within a much narrower range than the pycnidia. But perithecial formation of this fungus on PDA, V-8 juice agar, WALM and seed varied considerably depending upon isolate and culture media.

• Research in Plant Disease
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• v.12 no.2
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• pp.69-74
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• 2006

Basal rot of freesia caused by a Sclerotium sp. occurred at Incheon areas. Incidence of the disease reached up to 45% and averaged 17.0% in the fields. Typical symptoms consisted of sheath dry and leaf blight due to rots on basal leaves. The causal fungus was identified as Sclerotium sp. based on following mycological characteristics. The fungus formed sclerotia on cultural media and plant tissues, but did not produce asexual spores. On cultural medium, aerial mycelia of the fungus changed color from white to clay with cultural age and smelled musty odor. Numerous irregular and elliptical black microsclerotia of the fungus were formed on potato dextrose agar (PDA) after 5 days of incubation at $25^{\circ}C$ and sized $115{\sim}200{\times}95{\sim}150 (av. 145{\sim}126.5){\mu}m$. The fungus grew at $10{\sim}32^{\circ}C$ and $pH 4.0{\sim}8.5$. However, the optimal temperature and pH for mycelial growth of the fungus were $24^{\circ}C$ and 5.5 respectively. The isolate showed present pathogenicity to not only freesia but gladiolus in the pathogenicity test, and the symptoms were similar to those observed in the fields. Basal rot of freesia caused by Sclerotium sp. is firstly reported in Korea.

• Journal of Conservation Science
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• v.35 no.2
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• pp.117-129
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• 2019

In this study, black-glazed porcelain excavated from the Shinan shipwreck is analyzed to distinguish its characteristics. Glazes of Hong-Tang kiln are thin and exhibit little vitrification, whereas the Ci-Zhou-type and Cha-Yang kilns are similar in terms of their cross section. However, Raman mapping images reveal difference in the distribution area of magnetite. In this study, firing experiments are conducted to determine how iron oxides change properties in black glazes. The results show that when hematite is fired to a temperature greater than $1250^{\circ}C$, it becomes magnetite. Therefore, it is estimated that a firing temperature of approximately $1200^{\circ}C$ is suitable for the Hong-Tang kiln. In addition, glazes of the Ci-Zhou-type and Cha-Yang kilns are fired at approximately $1300^{\circ}C$. However, when the characteristics of firing in ancient kilns are considered, porcelain can be fired for a sufficiently long period to extend to glaze surfaces.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.1
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• pp.11-24
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• 2022

It has been reported that the ethanolic extract of the root of Piper methysticum (P. methysticum) inhibits melanogenesis in melanocyte stimulating hormone (MSH)-activated B16 melanoma cells. Flavokawain B (FKB) and Flavokawain C (FKC) isolated from this extract have been found to inhibit melanin production based on anti-melanogenesis activity. This study was designed to find out the inhibition and its process of FKB and FKC on melanin synthesis in melan-a melanocytes. FKB and FKC inhibited melanogenesis at 10 μM, 5 μM respectively in melan-a melanocytes. However, they did not inhibit extracellular tyrosinase activity from melan-a melanocytes. FKB reduced the protein level of tyrosinase (Tyr), tyrosinase-related protein 1 (TRP-1), tyrosinase-related protein 2 (TRP-2), microphthalmia-associated transcription factor (MITF) and the mRNA level of Tyr and TRP-1. FKC reduced the protein level of TRP-2 and MITF and the mRNA level of TRP-1 and Tyr. The reduced expression of Tyr and TRP-1 might be resulted from the decreased MITF which regulates major melanogenic proteins. However, since the mRNA expression of MITF did not change by FKB and FKC treatment, the effects of FKB and FKC on extracellular signal regulating kinase (ERK)/AKT phosphorylation, known to regulate the degradation of MITF, were confirmed. FKB and FKC significantly increased the phosphorylation of ERK1/2, not in AKT. These results suggest that FKB and FKC may be helpful as a potential depigmenting agent for various hyper-pigmentary disorders.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.245-252
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• 2010

The objective of this study was to obtain the basic informations on variability of germplasm and cultivation practice for the production of biodiesel in sunflower. A total of 275 accessions obtained from the National Agrobiodiversity Center (34 landraces from Korea, 219 and 22 introductions from America and other countries, respectively) were screened to evaluate variations of seed characteristics, oil content and fatty acid composition. Seed types were classified into 4 types (broad ovoid, narrow ovoid, rounded and elongated). The broad ovoid type was the highest proportion of 40.4%, while the elongated type was the lowest proportion of 5.0% among accessions. Also, the seed colors were classified into 4 colors (gray, brown, black and white). Gray and brown seed color showed the highest distribution and white seed color showed the lowest among accessions, respectively. Hundred and one liter seed weight ranged 2.9~15.5g and 178~439g with averages of 6.3g and 322.0g, respectively. Oil content ranged from 11.7% to 45.6% with an average of 25.5%. The frequency distribution of oil content showed the highest in range of 22~28% and the lowest in range of over 40%. Three promising accessions with higher oil content than 40.0% were IT031967, IT031970 and IT031965 introduced from America. Palmitic and stearic acid contents, saturated fatty acid, ranged 3.1~7.6% and 1.3~4.1% with averages of 4.7% and 2.2%, respectively, and a total content of saturated fatty acid ranged 5.4~9.4% with an average of 6.9%. Oleic and linoleic acid contents, unsaturated fatty acid, ranged 18.1~75.7% and 18.1~74.1% with averages of 55.2% and 38.0%, respectively. Five accessions, IT031831, IT031669, IT031895, IT031938 and IT031694, showed higher oleic acid content than 70%. A total content of unsaturated fatty acid ranged 89.6~94.8% with an average of 93.0%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.7-15
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• 2012

Agronomic characteristics of 150 adzuki bean ($Vigna$ $angularis$ W.F. Wight) germplasm collected in Korea were investigated in order to establish basic data for the improvement of crop breeding. Growth types were classified as 3 types of indeterminate type, determinate type, and semideterminate type, of which indeterminate type was the highest percentage of 96.6%. Seed color were classified as 8 colors of which dark brown took 66.5% in 150 adzuki bean germplasm. Days from seeding to maturity showed the range from 89 to 142 days with 115 days in the average and the highest frequency proportion was 37.2% of the group from 131 to 140 days, and the next was 27.3% of the group from 121 to 130 days among 150 germplasm. Pod length showed the range from 5.9 to 10.1 cm with 7.8 cm in the average and the highest frequency distribution of it was the group from 7.1 to 8.0 cm with the proportion of 45.1% and the next was the group from 8.1 to 9.0 cm with the proportion of 32.2%. Number of pods per plant showed the range from 5.0 to 132.5 pods with 28.5 pods in the average and the highest frequency distribution of it was the group from 11.0 to 20.0 pods with the proportion of 30.8% and the next was the group from 21.0 to 30.0 pods with the proportion of 28.6%. Number of seeds per pod showed the range from 5.3 to 11.3 seeds with 8.2 seeds in the average and the highest frequency proportion of it was the group from 7.1 to 8.0 seeds, which occupied 32.2% among 150 germplasm. 89.3% of 150 germplasm showed the resistance to shattering of grains at harvest period. 100 grain weight showed the range from 5.7 to 23.0 g with 12.9 g in the average and the highest frequency proportion of it was the group from 9.01 to 13.0 g, which occupied 43.3% and the next was the group from 13.01 to 17.00 g with the proportion of 28.5% of 150 germplasm.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.376-382
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• 2014

This work was conducted to investigate the variation of growth and yield among three generations ($TC_0$, $TC_1$, and $TC_2$) in the field cultivation of virus-free sweetpotato (Ipomoea batatas) plants. Virus-free generations of three cultivars ('Matnami', 'Shinhwangmi', and 'Yeonhwangmi') were cultivated with $75{\times}25cm$ planting density on May 20th, covered with black vinyl film. At 30 days after planting, vine growth in $TC_0$, $TC_1$, and $TC_2$ was significantly increased as compared to the farmer's plant, and vine length in $TC_0$ showed the highest growth among treatments. At harvesting time after 120 days, vine diameter, number of node, and number of branch in $TC_0$, $TC_1$, and $TC_2$ were more increased than farmer's plant, but were not statistically significant. Fresh weight of shoot in $TC_0$, $TC_1$, and $TC_2$ was significantly increased as compared to the farmer's plant, but was not statistically significant among generations or cultivars. Number of tuber per plant and mean weight of tuber in $TC_0$ and $TC_1$ showed significant increasement, but that in $TC_2$ did not show significant difference as compared to the farmer's plant. Weight of tuber per plant in $TC_0$, $TC_1$, and $TC_2$ was significantly increased as compared to the farmer's plant. Marketable yield, percentage of marketable tuber, and percentage of small tuber (40 to 200g) in $TC_0$, $TC_1$, and $TC_2$ was significantly increased as compared to the farmer's plant. The large tuber over 300g showed the lowest percentage in $TC_0$. Marketable yield in $TC_2$ was significantly decreased as compared to $TC_0$, and was not significantly different as compared to the farmer's plant. Marketable yield in 'Matnami' was highest among cultivars. From this results, Farmers are required to renew every three years to maintain the yield and quality of virus-free plants. However, the exchange period of virus-free plants is desirable to renew every 2 or 3 years according to the degree of virus reinfection.

• Journal of the Mineralogical Society of Korea
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• v.16 no.4
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• pp.333-339
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• 2003

A new mineral, Zn analogue of rancieite (Chimooite), has been discovered at the Dongnam mine, Korea. It occurs as compact subparallel fine­grained flaky or acicular aggregates in the massive manganese oxide ores which were formed by supergene oxidation of rhodochrosite­sulfide ores in the hydrothermal veins trending NS­N25E and cutting the Pungchon limestone of the Cambrian age. The flakes of chimooite are 0.2 mm for the largest one, but usually less than 0.05 mm. The acicular crystals are elongated parallel to and flattened on (001). This mineral shows gradation to rancieite constituting its marginal part, thus both minerals are found in one and the same flake. Color is bluish black, with dull luster and brown streak in globular or massive aggregates. Cleavage is perfect in one direction. The hardness ranges from 2.5 to 4. Under reflected light it is anisotropic and bireflectant. It shows reddish brown internal reflection. Chemical analyses of different parts of both minerals suggest that rancieite and chimooite constitute a continuous solid solution series by cationic substitution. The empirical chemical formula for chimooite has been calculated following the general formula, $R_2_{x}$ M $n^{4+}$$_{9­x}$ $O_{18}$ $.$n$H_2O$ for the 7 $\AA$ phyllomanganate minerals, where x varies from 0.81 to 1.28 in so far studied samples, thus averaging to 1.0. Therefore, the formula of Zn­rancieite is close to the well­known strochiometric formula $_Mn_4^{4+}$ $O_{9}$ $.$4$H_2O$. The mineral has the formula (Z $n_{0.78}$N $a_{0.15}$C $a_{0.08}$M $g_{0.01}$ $K_{0.01}$)(M $n^{4+}$$_{3.98}$F $e^{3+}$$_{0.02}$)$_{4.00}$ $O_{9}$ $.$3.85$H_2O$, thus the ideal formula is (Zn,Ca)M $n^{4+}$$_4$ $O_{9}$ $.$3.85$H_2O$. The mineral has a hexagonal unit ceil with a=2.840 $\AA$ c=7.486 $\AA$ and a : c = 1 : 2.636. The DTA curve shows endothermic peaks at 65, 180, 690 and 102$0^{\circ}C$. The IR absorption spectrum shows absorption bands at 445, 500, 1630 and 3400 c $m^{1}$. The mineral name Chimooite has been named in honour of late Prof, Chi Moo Son of Seoul National University.ity.versity.ity.y.