• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.2
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• pp.123-128
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• 2007

A study was conducted over two years to determine the temperate mixtures of grasses for grazing horses in Jeju, Korea. The experiment field located at 450 m altitude (Jeju Horse Training Center of Korea Racing Association) was divided into 3 different mixtures plots (3 replications) without a fence between treatments, and sown by three main grasses (orchardgrass, perennial ryegrass and timothy). Seven castrated adult horses were kept on pasture from the middle of April to the end of November without supplementary concentrates. The dry matter yield, percentage of grasses intake and botanical composition were determined during the grazing period. Nutrients in grasses and soils were analyzed. The dry matter yield during two-year experimental period was not different among mixtures (11,000-12,000 kg/ha/year). In botanical composition, perennial ryegrass was dominant in all mixtures during spring through early summer season, but faded away during hot summer season. Timothy seemed to be more resistant against a hot or dry weather than other grasses. The percentage of grasses intakes was higher in the mixture of timothy than those in other mixtures. The contents of NDF (neutral detergent fiber) and ADF (acid detergent fiber) were not different among different mixtures. These results indicate that the mixture of timothy, orchardgrass, perennial ryegrass and white clover (20, 5, 5, 2 kg/ha as a seeding rate) can be used for gazing pasture of horses in the high altitude of Jeju.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.29-33
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• 1984

From June 28th to July 17th in 1985, this study was performed to obtain the information of the fresh corn forage production through the spraying hydrophonics in summer. The experiments were conducted in vinyl house on Kyungpook University's Experimental Station. The results obtained were as follows: It was suggested that the treatment of soaking for 24 hrs and followed by the pretreatment for 48 hrs was better than other treatments. Seed cost for the production of 1 kg fresh forage was the most inexpensive at the seeding rate of 450 g per $30{\times}60cm$ tray than other seeding rates. Application of 1000 times diluted Hyponex solution (1000X Hyponex) or 300 times diluted Yogen solution (300X Yogen) one time per day resulted in the heavier fresh weight than the other treatments. Treatments of 300X Yogen and 500X Yogen gave the better fresh weight in one application per two days and per three days, respectively. But, this method was not useful in summer because the lowest seed cost for the production 1kg fresh forage was 73Won, and collection of the fresh forage from the mountain range was easy.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.287-304
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• 2021

Since 1995, researches on natural enemies have been conducted extensively in Korea. Research papers on natural enemies published in the Korean Journal of Applied Entomology from 1990 to 2020 were 130, which is 8.4% of all published papers during the same period. In 1990s, most research papers study the searching and biological characteristics of natural enemies, whereas the proportion of research papers related to the field application using the developed natural enemies has been increasing since 2010s. A total of 37 excellent natural enemies have been developed including 24 indigenous and 13 introduced natural enemies. In addition, 28 kinds of booklets and/or manuals were developed for field application of natural enemies. Although successes in research and development have been achieved since that period, more researches on search for and/or introduction of excellent natural enemy suitable for the Korean cultivation environment, mass production technology that can reduce cost, and quality control program in producing and distributing natural enemy remain to be pursued in the future. Furthermore, there is a need to develop the technology that can be used in compatible way with natural enemies and other crop protection agents including synthetic insecticides.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.15-22
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• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.3
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• pp.187-203
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• 2009

This study monitored marine environments in system coastal waters of the South Sea of Korea during the period of 2005-2007 and analyzed the data from environmental parameters and nutrients, which contributed to fluctuate marine environmental characteristics in aquaculture. On the basis of the fluctuation of temperature depending on seasons and sampling sites, too seasons of winter and summer showed a remarkable temperature gap of $5^{\circ}C$ compared with spring and autumn. Salinity in spring and summer approached 9 psu in Morkpo. Most of sampling sites showed COD below 2mg/L, indicating somewhat optimal environmental conditions. T-N and T-P also had desirable horizontal distributions all year round the concentration of SS was higher, but Chi. a was well-distributed horizontally except for Morkpo. Marone environmental parameters of surface water were similar to those of bottome water except for Morkpo. Most of sampling sites showed the ratio of N/P below 16, impling that nitrogen played an important role in growth of phytoplankton as a limiting factor. The relationship between Chi. a and nutrients was positive linear, whereas the relationship between Chi. a and COD were very strong positive. winder, Spring and Summer showed the strong relationship between Chi. a and COD. In the analysis of dendogram based on environmental parameters using SPSS ver. 10.0, the station 7 did not belong to other stations, and kept an independent place. The relationships of waters between Jindo, Wando and Heanam ware close, compared with other waters. Consequently, these regions except for Morkpo into which fresh water is introduced by the dike showed somewhat optimal environmental parameters and nutrients in year, and were assumed to maintain the desirable marine conditions for aquaculture.

• Journal of Aquaculture
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• v.13 no.2
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• pp.169-174
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• 2000

Reproductive cycle of U. unicinctus was studied from September 1998 to August 1999, using gonadosomatic index (CSI) as an indicator. In November, the CSI values were maximum for male (6.2) and female (7.0), respectively; the values were lowest for them (1.0 and 0.5) during the successive february. Subsequently, they rapidly increased and attained peak by March-April. The values decreased again in both sexes and remained unchanged until August. The index increased in October to attain the peak by November. The CSI values clearly indicated that there are two spawning events in a year, namely the first one during April-May and the second one in December. Reproductive cycle was classified into the following successive stages: in female, multipication (January~February, June ~Setember), maturation (March~April, November), spent (May and December), degeneration and resting (June and January), and in male, multiplication January ~ february, June ~September), maturation (March~April, October~November), spent (May and December) and degeneration and resting (January and June). Histological observations revealed that oocytes in the ovary matured simultaneously in November and March. At the same time, the envelopes of matured testis became thinner than those in the early stage.

• Journal of Mushroom
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• v.7 no.1
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• pp.1-8
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• 2009

Thirty strains of genus Agrocybe which had been kept in National Institute of Horticultural and Herbal Science, were tested for the formation of fruiting body. Nineteen strains of collected genus Agrocybe were formed fruiting body at bottle culture of sawdust medium. Five strains (including ASI 19003) and thirteen strains (including ASI 19007) could be grouped as A. cylindracea and A. chaxingu. Although ASI 19008 showed the formation of fruiting body, morphological characteristics were significantly different from the two groups. Cultural period of ASI 19003 strain at sawdust substrates was 29 days and ASI 19007 train was 30 days in liquid spawn inoculation. The yield and quality of ASI 19003 strain was excellent in the spring, fall, and winter, whereas ASI 19007 strain was excellent in the summer. Accordingly, these cultivar might be contribute to farmers' income by stable year-round production if using the season-oriented strain.

• Korean Journal of Medicinal Crop Science
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• v.9 no.3
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• pp.198-204
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• 2001

$GA_3$ treatments for seeds of Perilla frutescens var. acuta Kudo were evaluated as a means of improving the percent germination, and the interactions of $GA_3$, mulching, and sowing depth on seedling emergence were investigated in late sowing. Percentage germination of seeds treated with different concentration of $GA_3$ was the most effective in 100 ppm treatment for 24 hours. The germinability according to the seeds soaking time was not significantly different over 12 hours in 100 ppm $GA_3$. At high temperature $(25^{\circ}C\;and\;30^{\circ}C)$, percentage germination was significantly increased in 100 ppm ${GA_3}$ treatment. In late sowing (1th or 15th May), seedling emergence was significantly higher in 100 ppm $GA_3$ treatment than nontreatment, and that was significantly increased when the seeds treated with 100 ppm $GA_3$ were mulched with 10 mm rice hull after molding with 5 mm soil depth.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.94-97
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• 2003

In order to shorten cultivation periods of Agrocybe cylindracea, liquid spawn was used in place of sawdust spawn. Optimum culture condition of liquid spawn was PSB (potato extract sugar broth) medium, $25^{\circ}C$ temperature and pH 7.0. And, optimum inoculum volume was $10{\sim}15ml$. Two grams per liter of dry weight of the fungal mycelia were obtained with 10l of culture bottle with liquid spawn after 10 days. In 850 ml-bottle of sawdust media, cultivation period using liquid spawn (30 days) was five days shorter compared with the cultivation period in sawdust spawn (35 days). Also, complete growth of sawdust media was increased to 92% (liquid spawn) from 75% (sawdust spawn) and yield of fruiting bodies was increased to about 10%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5570-5575
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• 2013

This study was carried out to find prioritization and evaluation of importance factor for plant factory development direction. According to the results, experts have put profitability secure at the top of development of plant factory industry. It is urgently needed in economic sector that products from plants factory secure the market and adjust the shipping date through contract cultivation and year-round production. Also, illuminant technology is also important in technology development section and R&D. On the other hand, consumers do not yet fully understand the benefits of the plant factory, and this will lead to continued slow sales. Therefore, the government needs to draw up measures to support producers who cultivated agricultural products from plant factory.