• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.303-311
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• 2020

The acreage of tangerines in the U.S. sharply rose from 19,000 ha in 2009 to 27,000 ha in 2016, an increase of 42% in 7 years. Considering the recent surge in tangerine exports to Japan, the export volume of 6-7 thousand tons is highly likely to increase in the future. Therefore, the purpose of this study was to analyze the economic impact of U.S. tangerine imports on the Korean citrus industry under various scenarios. In order to examine the possibility of imports of U.S. tangerines, the unit price of U.S. exports to Japan was used since U.S. tangerines are not imported to South Korea. Citrus fruits are divided into field citrus, house citrus, and late-maturing citrus (including winter season citrus) based on the cultivation method and variety used to analyze. Considering both the field and house seasons, the import volume of U.S. tangerines can be expected to rise from roughly 4,700 tons in 2021 to 10,000 tons in 2027. Imports of U.S. tangerines may be pushed up or delayed depending not only on the harvest method and quality of domestic field and house citrus but also on the harvest of U.S. tangerines. However, it is necessary to note that tangerines could be imported after 2021, when the tariff rate on U.S. tangerines will fall below 50%.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.371-376
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• 2009

The fruits of sweet cherry are highly appreciated by the consumer due to their precocity and quality, such as their sweetness, color and sourness. In this study, the hot-water extract and its sequential organic solvent fractions were prepared from domestic Napoleon sweet cherry (Prunus avium L.) to investigate antimicrobial and antioxidant activity. The hot-water extract contained about 40% sugars, and the solvent fraction yields for hexane, ethylacetate (EA), butanol, and water residue were 0.01%, 3.45%, 16.30%, and 80.24%, respectively. Contents of total polyphenol and total flavonoid of the fractions were 1.24~5.24%, and 0~3.76%, respectively. Among the fractions, EA fraction showed the highest total polyphenol and total flavonoid concentrations. Evaluation of antimicrobial activity of the extract and fractions revealed that EA fraction and butanol fraction contained strong antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, and Salmonella typhimurium with minimal inhibitory concentration (MIC) of 0.5~1.0 mg/mL. But the extract and fractions tested were not active to Pseudomonas aeruginosa. In a while, only hexane fraction showed anti-Candida activity with 0.5~1.0 mg/mL of MIC. The fraction showed strong activity against different multi-antibiotics resistant strains such as C. albicans CCARM 14020. Antioxidative activity assay showed that EA fraction has a strong DPPH scavenging activity and a reducing power. The $IC_{50}s$ of vitamin E and EA fraction were 15.5 and $195.5\;{\mu}g/mL$, respectively. Our results suggest that the fruit of P. avium L. has high potentials with anti-Candida and antioxidative activity.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.275-279
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• 2005

The fruiting habit pattern of white-spine cucumber, whose fruits are usually borne on the lateral branches, is different from domestic ones. The cucumber production far export has been focused on how to promote lateral shooting and how to increase the number of lateral branches. As the growing season of the exporting cucumber is confined to winter season, low temperature and weak light are limiting factors to lateral shooting. This study was conducted to investigate the effect of foliar application of growth regulator for induction of lateral shoot in white-spine cucumber. foliar application of growth regulator were focused on concentration and application time based on number of leaves. The visible damages were observed in applied leaves by $30mg{\cdot}L^{-1}$ BA(benzyladenine) in retarding culture, but no significant by $10mg{\cdot}L^{-1}$ BA in case of semi-forcing culture. The number of available lateral shoots were greater in applied plant with $10mg{\cdot}L^{-1}$ BA than that of $30mg{\cdot}L^{-1}$ BA, in applied plants at 10th and 15th loaves than that of applied plants at 5th leaves.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.1
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• pp.63-72
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• 2017

Gardening activities, plant raising, and general flowerbeds the public makes today can be found in the original form of cottage gardens in the United Kingdom. A cottage garden is a popular garden style of modern Britain, implying unique Englishness including ethnic sense and vernacular. In addition, the purpose of this study is to consider the modern movement in the United Kingdom in the past 200 years and read Englishness of cottage gardens through style differentiation and background of occurrence of cottage gardens appearing in this process. Therefore, this study is summarized as follows. First, a view of nature of the Englishman loving freedom and landscape acts as a key part of patriotism and is connected to the preservation of idyllic England. For this ideal of the Englishman of the country, idyllic British characteristics are found in various literatures and artistic fruits; cottage gardens, that is a form of new garden, were made with invigoration of supply and collection of plants. Second, an early form of cottage gardens was the domestic garden, in which there is a vegetable garden by middle-class move to a suburb according to urbanization, but evolved into a form of garden having both artistry and regionality, vernacular, and ecological characteristics with various situations of modern society(handicraft promotion movement, preservation of remains, and ancient building restoration movement). Wild gardens occurring in this process are a type of garden realizing wild fields and forests in the United Kingdom;they have made a big impact on many garden designers up to now. Cottage gardens, reflecting a variety of Englishness, is a subject of city planning and flower shows and is a culture symbolizing the United Kingdom.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.263-269
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• 2021

Growth and fruit characteristics of 'Duke' highbush blueberry by mixture of different organic matters in soil were investigated. The soil acidity was 4.2 to 4.8, sawdust treatment was the highest, and peat soil and peatmoss treatments were similar. The organic matter content of the soil was 2.5% for sawdust and 4.1% for soil with peatmoss and peat soil. The soil hardness of all treatment was found to be about 1 ~ 5 kgf cm^-2 which was suitable for growing crops. The number of suckers and main stems were high in the order of peat soil, peatmoss, sawdust treatment. In addition, the blueberry plants in the peatmoss and peat soil treatments had thicker and longer suckers and more shoots than those in the sawdust treatment. Among the characteristics of fruit, there was no statistical difference between the organic materials treatment in weight, diameter, length, and hardness of fruit. However, the total soluble solid and fruit yield were high in the order of peat soil, peatmoss, sawdust treatment. Therefore, as a result of comprehensively reviewing the characteristics of growth and fruits according to the soil environment, it was determined that peatmoss could be replaced with peat soil for stable production in domestic blueberry cultivation.

• Research in Plant Disease
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• v.26 no.4
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• pp.239-249
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• 2020

To find out the cause of the fire blight outbreak in apples and pears of Korea in 2019, we investigated disease appearing situation of thirty fire blight infected orchards, and interviewed farmers to determine the cultivation characteristics. Fire blight occurred mostly in orchards that had infected more than 2 years before. The cause of this were as follows: farmers did not know the symptoms of the disease properly. It is presumed that it has spread from the first occurrence to the surrounding orchards by flower-visiting insects or farmers and to a short distance or a long distance by the same cultivator or co-farmer. These series of processes repeated in the newly spreading area, and then disease reports increased as farmers became aware of fire blight. To minimize the spread of fire blight in Korea, it suggested that thorough education of farmers for early diagnosis and quantitative detection technology that can diagnose even in no symptom showing plants. And chemical or biological spraying systems suitable for domestic cultivation methods, which are producing large fruits, and molecular epidemiological studies of pathogens.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.224-232
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• 2012

This study was performed to investigate the pesticide residue of commercial medicinal plants used for food materials in the Seoul area. Multi class pesticide multiresidue methods in Korea Food Code was used to analyze 100 pesticides. Analyzed samples were 261 cases(domestic 201, imported 60), detection rate was 19.2%(domestic 20.9%, imports 13.3%). 17 pesticides were detected in fruit(chinese matrimony vine, jujube, rubus coreanus, japanese cornlian cherry, schizandra, tangerine peel), and root(cnidium, licorice, astragalus). Pesticide over Maximum Residue Limits were detected in jujube, cnidium. Frequently detected pesticides were cypermethrin, chlorpyrifos, cyhalothrin, fenvalerate, bifenthrin. More than 50% of the sample were detected two or more pesticides at the same time. Because of the variety and increase of pesticide detection in medicinal roots and fruits, continued monitoring and safety management is required.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.574-583
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• 2005

To investigate the importance and practice of well-being related dietary life pattern such as purchasing food materials, food habits and eating out, a survey was conducted by questionnaire and 5-point Likert score in Seoul and Gyeonggi-Do, September, 2004 and April, 2005. The responses of 732 housewives who were over 40 years were analyzed by SPSS package program. The results were as follows. Most of them were 40-49 years(74.4%), graduated highschool (66.6%) and their family type was nuclear family type(81.4%). Almost half of them had full-time job (37.1%) and part time job (15.4%). The average importance score of 'food habits', 'purchasing food materials' and 'eating out' were $4.15{\pm}0.91,\;4.06{\pm}0.96\;and\;3.25{\pm}1.01$ respectively. But the average practice score of 'food habits' was greater($3.58{\pm}1.06$) than 'purchasing food materials ($3.19{\pm}1.19$)' and 'eating out($2.54{\pm}1.05$)'. Among 5 types of 'food habits', the type of 'cut down on eating fast food' had the greatest score of importances ($4.31{\pm}0.97$) but the difference between importance and practice was greatest(0.94). Also 'consume home-made food rather than processed or ready to food' showed great scores in importance ($4.28{\pm}0.87$) and practice($3.87{\pm}1.04$). 'Consume fruits and vegetables rather than meats' and 'avoid heavy use of oils' had the importance score of $4.04{\sim}4.19$. But the practice score of 'avoid heavy use of oils' was the lowest($3.39{\pm}0.97$). Among four types of purchasing of food materials, 'purchase domestic agricultural food' was greatest($4.37{\pm}0.78$) and 'don't purchase genetically modified food' 'purchase organic food' and 'purchase whole grain products' were also great ($3.92{\sim}3.99$). But the practice score of 'purchase organic/low chemical foods($2.77{\pm}0.98$)' and 'don't purchase genetically modified food($2.99{\pm}1.41$)' were lowest. 'Go to well being restaurant' in three types of 'eating out' showed greatest in importance($3.35{\pm}0.96$) but the practice score($2.47{\pm}0.10$) was lower than the importance score. Also 'choose menu with comparing calories' had the lower score in practice($2.45{\pm}1.06$) rather than importance score($3.22{\pm}1.03$). In regarding to 'food habits', the importance score were significantly affected by type of food expense (p<0.05) and health status (p<0.05). The importance score of 'purchase food materials' were significantly affected by the type of food expense (p<0.001), type of residence(p<0.05), and self assessment of weight(p<0.05). Monthly income, especially more 400 million won, was the commonly significant effector in practice score of 'purchase food materials' and 'eating out'.

• Korean Journal of Heritage: History & Science
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• v.44 no.1
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• pp.72-105
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• 2011

This study explores the value of the Dicentra spectabilis community as a nature reserve in provincial forests at San 1-2, Daea-ri, Dongsang-myeon, Wanju-gun, Jellabuk-do, also known as Gamakgol, while defining the appropriateness of its living environment and eventually providing basic information to protect this area. For these reasons, we investigated 'morphological and biological features of Dicentra spectabilis' and the 'present situation and problems of designing a herbaceous nature reserve in Korea.' Furthermore, we researched and analyzed the solar, soil and vegetation condition here through a field study in order to comprehend its nature reserve value. The result is as follows. According to the analytic result for information on the domestic wild Dicentra spectabilis community, it is evenly spread throughout mountainous areas, and there is one particularly outstanding in size in Wanju Gamakgol. Upon the findings from literature and the field study about its dispersion, Gamakgol has been discovered as an ideal district for Dicentra spectabilis since it meets all the conditions this plant requires to grow vigorously, such as a quasi-high altitude and rich precipitation during its period of active growth duration in May. Dicentra spectabilis grows in rocky soil ranging from 300~375m above sea level, 344.5m on average, towards the north, northwest and dominantly in the northeast. The mean inclination degree is $19.5^{\circ}$. Also, upon findings from analyzing solar conditions, the average light intensity during its growth duration, from Apr. to Aug., is 30,810lux on average and it tends to increase, as it gets closer to the end. This plant requires around 14,000~18,000lux while growing, but once bloomed, fruits develop regardless of the degree of brightness. The soil pH has shown a slight difference between the topsoil, at 5.2~6.1, and subsoil, at 5.2~6.2. Its mean pH is 5.54 for topsoil and 5.58 for subsoil. These results are very typical for Dicentra spectabilis to grow in, and other comparative areas also present similar conditions. Given the facts, the character of the soil in Gamakgol has been evaluated to have high stability. Analysis of its vegetation environment shows a wide variation of taxa numbering from 13 to 52 depending on area. The total number of taxa is 126 and they are a homogenous group while showing a variety of species as well. The Dicentra spectabilis community in the Daea-ri Arboretum is an herbaceous community consisting of dominantly Dicentra spectabilis, Cardamine leucantha, Boehmeria tricuspi and Impatiens textori while having many differential species such as Impatiens textori, Pueraria thunbergiana, Rubus crataegifolius vs Staphylea bumalda, Securinega suffruticosa, and Actinidia polygama. It suggests that it is a typical subcolony divided by topographic features and soil humidity. Considering the above results on a comprehensive level, this area is an excellent habitat for wild Dicentra spectabilis providing beautiful viewing enjoyment. Additionally, it is the largest wild colony of Dicentra spectabilis in Korea whose climate, topography, soil conditions and vegetation environment can secure sustainability as a wild habitat of Dicentra spectabilis. Therefore, We have determined that the Gamakgol community should be re-examined as natural asset owing to its established habitat conditions and sustainability.

• Journal of Aquaculture
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• v.5 no.1
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• pp.29-67
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• 1992

Life cycle and seed production of the freshwater prawn, Macrobrachium nipponense, were studied and the results are as follows : 1. Larval development : Embryos hatched out as zoea larvae of 2.06 mm in mean body length. The larvae passed through 9 zoea stages in $15{\~}20$ days and then metamorphosed into postlarvae measuring 5.68 mm in mean body length. Each zoea stage can be identified based on the shapes of the first and second antennae, exo- and endopodites of the first and second pereiopods, telson and maxillae. 2. Environmental requirements of zoea larvae : Zoea larvae grew healthy when fed with Artemia nauplii. Metamorphosing rate was $65{\~}72{\%}$ at $26{\~}28\%$ and $7.85{\~}8.28\%_{\circ}Cl.$. The relationship between the zoeal period (Y in days) and water temperature (X in $^{\circ}C$) is expressed as Y=46.0900-0.9673X. Zoeas showed best survival in a water temperature range of $26{\~}32^{\circ}C$ (optimum temperature $28^{\circ}C$), at which the metamorphosing rate into postlarvae was $54{\~}72\%$ The zoeas survived more successfully in chlorinity range of $4.12{\~}14.08{\%_{\circ}}Cl.$, (optimum chlorinity $7.6{\~}11.6\;{\%_{\circ}}Cl.$.), at which the metamorphosing rate was $42{\~}76{\%}$. The whole zoeal stages tended to be longer in proportion as the chlorinity deviated from the optimum range and particularly toward high chlorinity. Zoeas at all stages could not tolerate in the freshwater. 3. Environmental requirements of postlarvae and juveniles : Postlarvae showed normal growth at water temperatures between $24{\~}32^{\circ}C$ (optimun temperature $26{\~}28^{\circ}$. The survival rate up to the juvenile stage was $41{\~}63{\%}$. Water temperatures below $24^{\circ}C$ and above $32^{\circ}$ resulted in lower growth, and postlarvae scarcely grew at below $17^{\circ}C$. Cannibalism tended to occur more frequently under optimum range of temperatures. The range of chlorinity for normal growth of postlarvae and juveniles was from 0.00 (freshwater) to $11.24{\%_{\circ}}Cl.$, at which the survival rate was $32{\~}35\%$. The postlarvae grew more successfully in low chlorinities, and the best growth was found at $0.00\~2.21{\%_{\circ}}Cl.$. The postlarvae and juveniles showed better growth in freshwater but did not survive in normal sea water. 4. Feeding effect of diet on zoea Ilarvae : Zoea larvae were successfully survived and metamorposed into postlarvae when fed commercial artificial plankton, rotifers, and Artemia nauplii in the aquaria. However, the zoea larvae that were fed Artemia nauplii and reared in Chlorella mixed green water showed better results. The rate of metamorphosis was $68\~{\%}75$. The larvae fed cow live powder, egg powder, and Chlorella alone did not survive. 5. Diets of postlarvae, juveniles and adults : Artemia nauplii and/or copepods were good food for postlarvae. Juveniles and adults were successfully fed fish or shellfish flesh, annelids, corn grain, pelleted feed along with viscera of domestic animals or fruits. 6. Growth of postlarvae, juveniles and adults : Under favorable conditions, postlarvae molted every five or six days and attained to the juvenile stage within two months and they reached 1.78 cm in body length and 0.17 g in body weight. The juveniles grew to 3.52 cm in body length and 1.07 g in body weight in about four months. Their sexes became determinable based on the appearance of male's rudimental processes (a secondary sex character) on the endopodites of second pereiopods of males. The males commonly reached sexual maturity in seven months after attaining the postlarvae stage and they grew to 5.65 cm in body length and 3.41 g in body weight. Whereas the females attained sexual maturity within six to seven months, when they measured 4.93 cm in body length and 2.43 g in body weight. Nine or ten months after hatching, the males grew $6.62{\~}7.14$ cm in body length and $6.68{\~}8.36$ g in body weight, while females became $5.58{\~}6.08$ cm and $4.04{\~}5.54$ g. 7. Stocking density : The maximum stocking density in aquaria for successful survival and growth was $60{\~}100$ individuals/$\ell$ for zoeas in 30-days rearing (survival rate to postlarvae, $73{\~}80{\%}$) ; $100{\~}300$ individuals/$m^2$ for postlarvae of 0.57 cm in body length (survival rate for 120 days, $78{\~}85{\%}$) ; $40{\~}60$ individuals/$m^2$ for juveniles of 2.72 cm in body length (survival rate for 120 days, $63{\~}90{\%}$) : $20{\~}40$ individuals/$m^2$ for young prawns of 5.2 cm in body length (survival rate for 120 days, $62\~90{\%}$) ; and $10\~30$ individuals/$m^2$ for adults of 6.1 cm in body length (survival rate for 60 days, $73\~100{\%}$). The stocking density of juveniles, youngs and adults could be increased up to twice by providing shelters.