• The Plant Pathology Journal
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• v.38 no.1
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• pp.46-51
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• 2022

Rice blast is the most destructive disease threatening stable rice production in rice-growing areas. Cultivation of disease-resistant rice cultivars is the most effective way to control rice blast disease. However, the rice blast resistance is easy to breakdown within years by blast fungus that continually changes to adapt to new cultivars. Therefore, it is important to continuously monitor the incidence of rice blast disease and race differentiation of rice blast fungus in fields. In 2020, a severe rice blast disease occurred nationwide in Korea. We evaluated the incidence of rice blast disease in Yeoju and compared the weather conditions at the periods of rice blast disease in 2019 and 2020. We investigated the races and avirulence genes of rice blast isolates in Yeoju to identify race diversity and genetic characteristics of the isolates. This study will provide empirical support for rice blast control and the breeding of blast-resistant rice cultivars.

• Journal of Ginseng Research
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• v.39 no.4
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• pp.338-344
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• 2015

Background: Ginseng (the roots of Panax ginseng Meyer) is a well-known traditional Oriental medicine and is now widely used as a health food. It contains several types of ginsenosides, which are considered the major active medicinal components of ginseng. It has recently been reported that the qualitative and quantitative properties of ginsenosides found in ginseng may differ, depending on cultivation regions, ages, species, and so on. Therefore, it is necessary to study these variations with respect to cultivation ages and regions. Methods: In this study, 3-6-yr-old roots of P. ginseng were collected from three different cultivation regions. The contents of five ginsenosides (Rb1, Rd, Rc, Re, and Rgl) were measured by rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry. The Kruskal-Wallis Rank sum test and multiple t test were used for comparative analysis of the data to evaluate the dynamic changes in the accumulation of these ginsenosides affected by cultivation regions and ages. Results: The content and composition of ginsenosides varied significantly among specimens collected from different cultivation regions and having different cultivation ages. For all samples, the content of Rg1 and Re ginsenosides increases with age and this rate of increase is different for each sample. The contents of Rb1, Rc, and Rd varied with cultivation ages in samples from different cultivation regions; especially, Rb1 from a 6-yr-old root showed approximately twofold variation among the samples from three cultivation regions. Furthermore, the content of Rb1 highly correlated with that of Rd (r = 0.89 across all locations and ages). Conclusion: In our study, only the contents of ginsenosides Rg1 and Re were affected by the root age. Ginsenosides Rb1, Rc, and Rd varied widely with ages in samples from different cultivation regions.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.35-47
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• 2018

A edible mushroom, Clitocybe maxima (Lentinus giganteusis) commercially cultivated in China and Taiwan. However, the researches of cultivation and cultural characteristics were not reported in Korea. In this study, we conducted on cultural characteristics and artificial cultivation of C. maxima. Six isolates were collected from China(3 isolates, commercial strain), Taiwan(1 isolate, commercial strain) and Korea(2 isolates, wild type). C. maxima and L. giganteus collected in China and Taiwan, respectively, are the same in China and are estimated to be of the same species as cultured characteristics. The mycelial growth of the collected strains was not significantly different in agar medium but it showed the best growth in YPMG in liquid culture. Optimum temperature for mycelial growth and induction of fruit body were 25℃ and 30℃, respectively. In order to artificial cultivation of C. maxima, cultural characteristics and artificial cultivation were carried out using agricultural by-products and forestry by-products materials. Mycelial growth was suitable in rice straw, cottonwood sawdust, corncob and rice seed medium, and it was selected as a cultivation medium. The suitable medium for artificial cultivation of C. maxima was selected to mixed medium 2(compounding ratio(v/v): 55% of hardwood sawdust, 5% of cottonseed pellets, 10% of cottonseed, 15% of beet pulp, 15% of swollen rice husks). It took about 30 days to be able to harvest, it was faster than oyster mushrooms. The cultivation period was about 30days. A isolate, CMA-002 was not initiation to fruit body primordiuma on the used cultivation substrate. Other 5 isolates were initiate and development to fruit body on the substrate used in this study. The strain CMA-003 was initiated to be fruiting body by 8~10 days after induction of fruiting body in all of the substrates. Isolate CMA-003 was generate to a bundle fruit body. Other isolates, however, were form fruit body individually. The CMA-003 strain was likely highly recommendable strains for farming. The optimum conditions for the induction and growth of C. maxima fruit body were 25~30℃, 8 hr illumination per day with white fluorescent lamp, 90~95% relative humidity, and 1,500 ppm of CO₂ concentration in a cultivation room.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.447-453
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• 1999

Salt accumulation is one of themajor problems in soils under protected cultivation . Since protected cultivation does not have rainfall or excessive irrigation, salt accumulaiton inthe soils is inevitable. In this study, characteristics of salt accumulation in soil column were ivestigated, and a salt-extracting method was tested to see its effectiveness. The results showed that the concentration of salt in top soil layers increased and electrical conductivity as thesalt concentration decreased especially in the top soil layer .When extraction medium was applied.

• Perspectives in Nursing Science
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• v.12 no.2
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• pp.124-127
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• 2015

Purpose: This article discusses nurses' moral dilemma and self-cultivation from the Foucauldian viewpoint. Methods: The philosophical inquiry approach is utilized to analyze the nurses' moral distress. Analyses are based on Foucauldian perspectives. Results: Foucault's codes of conduct comprising the mode of subjection and telos are discussed to explain nurses' moral dilemma. The dual process of caring is also discussed. Conclusion: From dilemmatic experience, nurses practice self-formation or self-cultivation to become more virtuous, well-balanced, or integrated people. Such characteristics form the essence of nursing practice.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.49-54
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• 2009

Cultivation characteristics of 12 strains of cauliflower mushroom (Sparassis crispa) collected in Korea were investigated by growing the mushroom on sawdust medium of Larix kaempferi. As cultivation characteristics, incubation period for full growth of mycelium in a cultivation bottle, cultivation time period taken for first harvest, and mushroom color and yield were examined. S. crispa KFRI 723 showed the shortest for incubation period with 59 days while S. crispa KFRI 746 showed the longest with 94 days. The earliest mushroom harvesting was achieved by 29 days from S. crispa KFRI 746 and the latest was by 63 days from S. crispa KFRI 691. The colors of fruit body of the tested strains can be divided into three groups; S. crispa KFRI 700 was white, S. crispa KFRI 747 was yellow brown, and the others were light yellowish. KFRI 700 yielded the most as 163 g from 380 g sawdust media, while KFRI 746 and KFRI 747 were the lowest with 58 g and 35 g, respectively. As results of cultivation characteristics of 12 strains of cauliflower mushroom, we consider that three strains (KFRI 700, 723 and 724) of S. crispa are suitable for sawdust cultivation on L. kaempferi in the aspects of mycelial growth period, harvesting period and mushroom production, respectively.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.21-21
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• 2014

A edible mushroom, Hypsizygus marmoreus is commercially cultivated in Northeast Asia. Japan's annual production is 110,000ton or more. Since 2002, cultivation is expanded in Korea. To investigate the morphological, cultural and microscopic characteristics of Hypsizygus marmoreus, 109 isolates were collected from Korea and other countries. Clamp connection, chlamydospore and arthrospore were present in all tested isolates of H. marmoreus except HYM-002 and HYM-004. Also pilealtrama, gilltrama, basidia, basidiospore and cystidia of fruiting body were no difference among the isolates in the present investigation. Morphological characteristics of fruiting body was that color of pileus was brown and white, irregular as marble, the average size 12~22mm and stipes was $46{\sim}91{\times}6{\sim}10mm$. Isolates HYM-031, HYM-047 and HYM-109 formed grayish-brown pileus with a faint pattern. Molecular analysis with RAPD and ITS rDNA sequence analysis were also performed to check the genetic relationships among H. marmoreus isolates. Based on the RAPD analysis using the URP-PCR, all isolates of H. marmoreus were clustered into large 3 groups but more than 90% showed high similarity. In addition, morphological and geographical differences have been classified as an independent cluster. The brown and white strains enclosed in same cluster. So genetically no significance difference was observed between these two strains. ITS gene sequences of 16 selected isolates which were 640 bp long, were aligned and compared. The similarity in ITS sequence was 94.8 to 99.1% among tested isolates and the H. marmoreus isolates in GeneBank. In conclusion the tested isolates were H. marmoreus. Morphological and molecular observations proved that all tested isolates were belonging to H. marmoreus. For the stable artificial cultivation, composition of optimum media, mature period and light condition were established. Optimal formula of artificial cultivation medium was Douglas sawdust: corn cob: soybean meal: wheat bran = 40:30:15:15. In addition, 7% rice bran and 3% yellow sucrose was the most effective composition for spawn's liquid medium. For the maturation of the isolates was favorable for growing for 20 to 30 days at $25^{\circ}C$ and the LED lights in mixture of white and blue was good for growth period. For effective growth, the temperature, humidity and aeration control in every step was important.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.97-97
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• 2022

The yield characteristics of corn for feed by sowing period and the crude protein, crude fat, and coarse flour contents of grain in the harvesting period were compared. The varieties are Kwangpyeongok(KPO), Dapyeongok(DPO) and Pyeonggangok(PGO), and cultivation was tested by the National Food Engineering Department and the Central Crop Department. It was sown at a planting distance of 70×25cm on April 15, June 14, and July 15, 2021, and the amount of fertilizer was applied through soil inspection. For the growth characteristics, plant height, biomass and grain weight were investigated after 50 days of sowing, and general components were analyzed by drying and pulverizing each seed. Compared to the results of sowing in April, which is the right time to sow corn, all three varieties sown on June 14 showed an increase in biomass. In the case of sowing on July 15, the fresh weight of KPO and DPO decreased, and the grain weight of KPO and PGO decreased by 10-20% compared to the sowing in April. There was no significant difference in the crude protein content of grain according to the sowing seasons in April and June, but decreased in the corn sown in July. The crude fat content was highest in KPO sown on June 14 and DPO sown on July 15. Combining the yield and general composition results, it is thought that the cultivation of corn for feed in Suwon in the central part can be sown by mid-June.

• Plant Resources
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• v.5 no.2
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• pp.165-168
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• 2002

This study was carried out obtain basic information for growth characteristics by different age of Dendropanax morbifera in chonnam, such as Yosu, Sunchon, Haenam, Gangjin, Wando. The pH of soil in cultivation area was 5.2 to 5.6 and organic matter was very high up to 10.6% . P205 content of soil in cultivation area was 35.3 to 42.1 mg/L, C.E.S was 13.9 to 14.4 me/100g, and moisture rate was 19.2 to 21.1 % . The flowering of Dendropanax morbifera began from 6~7 years old tree. The flowering date was at 10th of July at Wando. The growth characteristics of 12 years old tree was 929.5cm in stem height, 134.1mm in stem diameter, and 15 years old tree was 1,117.9cm in stem height, 160.8mm in stem diameter. The number of leaf was 13.9 at five years old tree, and the petioles length was 12.6 at five years old tree. Xylem sap can be had at more than 10 years old tree with good growth more than 10 em stem diameter.

• Plant Resources
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• v.3 no.2
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• pp.148-151
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• 2000

This study was carried out obtain basic information for growth characteristics by different age of Dendropanax morbifera in southern part of Korea, such as at Sunchon, Haenam, Gangjin, Wando. The pH of soil in cultivation area was 5.2 to 5.6 and organic matter was very high up to 10.6%. P$_{2}$O$_{5}$, content of soil in cultivation area was 35.3 to 42.1 mg/1, C.E.S was 13.9 to 14.4 me/100g, and moisture rate was 19.2 to 21.1 %. The flowering of Dendropanax morbifera began from 6~7 years old tree. The flowering date was at 10th of July at Wando. The growth characteristics of 12 years old tree was 929.5cm in stem height, 134.1mm in stem diameter, and 15 years old tree was 1,117.9cm in stem height, 160.8mm in stem diameter. The number of leaf was 13.9 at five years old tree, and the petioles length was 12.6 at five years old tree. Xylem sap can be had at more than 10 years old tree with good growth more than 10 cm stem diameter.r.