• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.162-167
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• 2016

This study was carried out to investigate proper stem cutting position and air temperature to regenerate roots from cuttings of bitter gourd. 'NS454' (NS) and 'Dragon' (DR) cultivars were tested and the cutting position was cut at the 3rd node in the stem (treatment I) and cut at the central part (stem segment) between 3rd leaf and 4th leaf in the stem (treatment II). The air temperature was maintained at 18, 23, 28 and $35^{\circ}C$ in the growth chambers, respectively. The photosynthetic photon flux at the ground of a chamber was maintained in approximately $150-200{\mu}mol\;m^{-2}s^{-1}$ during the 16-hour photoperiod. The relative humidity in the chambers was maintained over 85%. After 10 days of cuttings, regardless of cutting position, DR and NS cultivars showed 100% the survival rate in the $18^{\circ}C$ or $23^{\circ}C$ treatments, however, most of plants $18^{\circ}C$ treatment had not rooting. In the $28^{\circ}C$ treatment, regardless of cutting position, DR and NS cultivars showed 100% of the rooting rate. In the $23^{\circ}C$ treatment, for DR cultivar, the node cutting showed 90% of rooting rate and the stem segment cutting showed 40% rooting rate. For NS cultivar, the node cutting showed 50% of rooting rate and the stem segment cutting showed 40% rooting rate. DR and NS cultivars have high rooting rate, while the rooting rate remarkably decreased in the $35^{\circ}C$ treatment. For DR cultivar, the stem segment cutting showed 5.3 of the highest rooting number and the node cutting showed 2.7 rooting number in the $28^{\circ}C$ treatment. NS cultivar was not significantly different the rooting regardless of cutting position. The results suggested that cutting at the stem segment cutting of bitter gourd is an effective cutting method for increasing survival rate and the air temperature should be maintained at $28^{\circ}C$.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.242-248
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• 2016

This research was conducted to determine the effects of four different substrates, expanded rice hulls (ERH), commercial substrates for strawberries (CSS), clay sand (CS), and loamy sand (LS), on the inhibition of anthracnose crown rot (ACR) in strawberry. Mother plants of 'Seolhyang' strawberry were transplanted into an elevated bed in March, 2013 and March, 2014 and the runners connecting mother plants and daughter plants were cut in early August of both years. After separation, growth characteristics of the daughter plants were measured and then each daughter plant was inoculated with conidial suspensions of Colletotrichum fructicola, one of several species of Colletotrichum that causes ACR in strawberries. The incidence of ACR as influenced by the different substrates was investigated in both years. The daughter plants grown on CSS had the highest values for shoot height, leaf area, and fresh weight. Those grown on ERH and LS substrates also displayed good above-ground growth characteristics except for fresh weight, but the daughter plants grown on CS had the poorest above-ground growth characteristics. The ERH and CS treatments resulted in the highest number of primary roots and the greatest root weight. The CSS-grown daughter plants had the highest ACR disease index, followed by the CS and LS treatments, but there were no significant differences among the three substrates. However, the ERH-grown daughter plants had a markedly lower ACR disease index on October 11, 2013 and October 7, 2014. The CSS-grown daughter plants had high nitrogen and potassium contents and low calcium content, whereas the ERH-grown daughter plants had low nitrogen levels and high silicon levels. The results of this study provide basic information on the ability of the different substrates tested to provide disease suppression of ACR in the propagation of strawberry transplants.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.361-366
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• 1996

Acceptable fish noodles of better nutritional and sensory values than conventional noodle made only wheat flour were prepared by mixing wheat flour and ground tile fish (Branchioste gus japonicus). In oder to mask a distinctive fish odor, various herbs and spices, such as ginger (Zingiber officinale), curry (Chalcas koenigii), nutmeg (Myristica Pagrans), garlic (Ailium sativum), black pepper (Piper nigrum), lemon (Cirtus limon) or sodachi (Citrus sudachi) were added to the basic tile fish noodle. Also, for the purpose of enhancing eating qual ify and nutritional value of basic noodle were combined some agricultural or fishery products of Cheju island, citrus fruits; danyooja (Citrus danyooga), hagul (C. natfudaidai), medical plants; angelica utilis (Angelica keiskei), ginseng (Panax ginseng), cactus (Opuntia dillenii), vegetable; carrot (Daucus carota), dropwort (Oenanthe jnvanica), seaweeds; fusiforme (Hizkia fusiforme), gulfweed (Sargaceae hlvelium). The optimal mixing ratio for preparing the basic tile fish noodle amounted to ground tile fish 135 g: tile fish stock 139 $m\ell$: wheat flour 450 g: salts 10 g. The mixture of curry powder (2.5 g) and nutmeg powder (2.5 g) was proved to be the most effective combinations for masking unfavorable fish odor. The optimal amounts of materials to be added to the prepared basic noodle were 25 g citrus zest and 80m1 citrus juice for citrus fruits noodles, and ca. 140 g puree for noodles from medical plants, vegetables and seaweeds, respectively. The preference score obtained from consumer preference test, on a 9-point scales, were in oder of i) danyooja > carrot, angelica, ginseng > fusiforme, ii) hagul > dropwort, cactus > gulfweed. The shelf-life of tile fish noodle based on bacterial counting was estimated to be 7-days at 5$^{\circ}C$.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.103-108
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• 1981

The antibiotic-producing Streptomyces strains were isolated from the soils of various localities in Yeang-Kwang and tested for the activity against some of gram positive and negative microorganisms, especially against Pseudomonas aeruginosa. The results are summarized as follows. 1. A total of 1464 Streptomyces strains were isolated from 336 soil samples. Of all the strains tested, 636 strains of the isolates showed antibiotic activity against either gram positive or negative test organisms. And 408 of the 636 strains were strongly active against one or all of those test­organisms. 2. Ninety-three of Streptomyces strains among the active isolates showed the antibiotic activity against Pseudomonas aeruginosa, and 24 of 93 strains showed the strong antibiotic activity against all of the test organisms i.e. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhi and Shigella jlexneri. 3. Antibiotic-producing Streptomyces strains active against Pseudomonas aeruginosa were isolated from the soil samples taken from vegetable field, paddy field, sandy ground and roadway, but not isolated from the soil taken from dwelling area, grass field and piers.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.6
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• pp.328-333
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• 2006

All the plants on earth live under an electric and magnetic field because the earth is a magnet and there is an electric field between the charged cloud and the ground. It has been reported that electromagnetic fields influence both the activation of ions and polarization of dipoles in living cells of seeds and plants, though the mechanism of these actions is still poorly understood. In this paper, the effects of the electric and magnetic fields and exposure times to the germination of several vegetable seeds and its early growth have been investigated experimentally to find out the feasibility of a plant factory for mass production of clean and unpolluted vegetables. The germination rate and the growth rate of some seeds under the fields exposed were analysed and compared with those of unexposed ones. It is found that the germination rate and its early growth rate of exposed seeds under the fields were accelerated about 1.1-1.4 and 1.7-2.2 times in maximum compared with those of unexposed ones. But, however, an inhibitory effect on germination and plant early growth were shown in the case of the higher electric and magnetic fields.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.220-227
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• 2016

The objective of this research was to investigate the influence of application rates of dolomitic lime in the acid substrate on the mitigation of high bicarbonate damage in 'Seolhyang' strawberry. For this purpose, an acid substrate was formulated by mixing of sphagnum peat moss and pine bark with the ratio of 5:5 (v/v). The pH, EC and CEC of the substrate analyzed before application of dolomite were 4.07, $0.46dS{\cdot}m^{-1}$, and $91.3cmol+/kg^{-1}$, respectively. To adjust the pH of substrate, various amounts of dolomitic lime [$CaMg(CO_3)_2$] such as 0 (control), 1, 2, 3, and $4g{\cdot}L^{-1}$ were added during substrate formulation. Then, seedlings with 3 leaf stage were transplanted as mother plants and those were fed with Hoagland solution containing $240mg{\cdot}L^{-1}$ of the $HCO_3{^-}$. The growth parameters of mother plants 140 days after transplanting, such as plant height, chlorophyll content, and fresh weight were the highest in the treatments of 2 and $3g{\cdot}L^{-1}$ of dolomitic lime. The physiological disorders in mother plants were not observed in the 1, 2 and $3g{\cdot}L^{-1}$ treatments, but the symptoms of Ca, K and B deficiencies were observed in the 0 and $4g{\cdot}L^{-1}$ treatments. During the propagation period, the number of daughter plants derived from each mother plant were 21.0, 29.5, 35.8, 27.3 and 16.0 in the treatments of 0, 1, 2, 3 and $4g{\cdot}L^{-1}$, respectively. The substrate pH during cultivation of mother plants were maintained at appropriate levels for the 1 and $2g{\cdot}L^{-1}$ treatments, whereas it was the highest in $4g{\cdot}L^{-1}$ treatment. The contents of macro- and micro-elements in the above ground tissue were the highest in $2g{\cdot}L^{-1}$ and the lowest in $4g{\cdot}L^{-1}$ lime treatments. Above results suggest that the bicarbonate injury originated from ground water can be mitigated by adjusting the amount of dolomitic lime incorporated into the acid substrate.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.657-663
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• 2012

The Ca deficiency is a serious problem in the propagation of domestically bred 'Seolhyang' strawberry through soil cultivation. The objective of this research was to investigate the impact of the Ca containing fertilizers on the decrease of Ca deficiency symptoms and in the growth of mother and daughter plants. To achieve this, chemicals of 1.125 mM $Ca(OH)_2$, 0.375 mM $MgCl_2$, and 1.25 mM KCl were blended to contain the K:Ca:Mg (4:2:1) and the influence was compared to a commercial fertilizer, Azuro-Calma ($NO_3$-N 13%, $K_2O$ 1%, CaO 16%, MgO 6%), when those were applied as solutions with the electrical conductivity (EC) controlled to 0.6 or 1.0dS ${\cdot}m^{-1}$. During 120 days after transplant, the Azuro-Calma was more effective than the combined fertilizer in the reduction of mother and daughter plants on which Ca deficiency was appeared. The application of two Ca containing fertilizers resulted in the heavier fresh and dry weights of mother plants. The treatments of 1.0dS ${\cdot}m^{-1}$ of two fertilizers were more effective than those of 0.6dS ${\cdot}m^{-1}$. The combined fertilizer was also more effective than Azuro-calma on the growth of above ground plant tissue. The results in length, fresh and dry weight of runners occurred from a mother plants showed that the treatment of 1.0dS ${\cdot}m^{-1}$ of combined fertilizer was most effective followed by those of 1.0dS ${\cdot}m^{-1}$ of Azuro-Calma, 0.6dS ${\cdot}m^{-1}$ of combined fertilizer, 0.6dS ${\cdot}m^{-1}$ of Azuro-Calma, and control. The fresh weights of daughter plants were heavier in the treatments of Ca application than those in the control treatment, but the differences between 0.6dS ${\cdot}m^{-1}$ and control were not significant. The above results indicate that Azuro-Calma is more effective in decreasing plants showing the Ca deficiency symptoms. However, the combined fertilizer of K:Ca:Mg is more desirable when we are concerned about the decrease of crops showing Ca deficiency as well as increase of the growth in above ground plant tissue.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.342-351
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• 2019

The optimum N concentrations incorporated as pre-planting nutrient charge fertilizer were determined for seedling raising using cylindrical paper pots. A root medium was formulated by blending of peat moss (particles smaller than 2.84 mm were 80-90%) and perlite (1 to 3 mm) with the ratio of 7:3 (v/v). The treatment N concentrations incorporated during the root medium formulation were adjusted to 0, 150, 250, 500, and $750mg{\cdot}L^{-1}$ and the concentrations of essential nutrients except N were equal in all treatments. After making of paper pots and putting into the 40-cell tray, the seeds of Chinese cabbage ('Chunmyeong Bom Baechu') and pak-choi ('Hanog cheonggyeongchae') were sown. During the raising of seedlings, weekly analysis of medium pH, EC and concentrations of inorganic elements were conducted. After 21 and 20 days after seed sowing of Chinese cabbage and pak-choi, the growth of the above-ground parts were measured and contents of inorganic elements in the plant tissues were analyzed. During the growing period, pH of the root media rose gradually and the EC decreased rapidly at week 3. The pH of root media at harvest was in the range of 5.3 to 5.9 in Chinese cabbage and 4.93 to 5.39 in pak-choi. Growth of the aboveground parts in terms of fresh and dry weight in both the plants were the highest in the $250mg{\cdot}L^{-1}$ N treatment and the lowest in the control treatment. The elevation of pre-planting N concentrations in root medium resulted in the increase of tissue N content and decrease of P, Ca, and Mg contents. The regression equation derived from the influence of varied pre-planting N concentrations on dry weight of above-ground tissue were $y=-0.0036x^2+0.0021x+0.0635$ ($R^2=0.9826$) in Chinese cabbage and $y=-0.16x^2+0.0009x+0.032$ ($R^2=0.991$) in pak-choi. When the low critical concentration of pre-plant N is taken at the point where dry weight of above-ground tissue is 10% less than maximum (0.40 g in Chinese cabbage and 0.16 g in pak-choi), those point are 0.36 g and 0.144 g per plant in Chinese cabbage and pak-choi, respectively. The lower critical N concentrations of root media calculated from the regression equations are $196mg{\cdot}L^{-1}$ for Chinese cabbage and $187mg{\cdot}L^{-1}$ for pak-choi. These results indicate that optimum pre-plant N concentrations for seedling raising using paper pots are in the range of 196 to $250mg{\cdot}L^{-1}$ for Chinese cabbage and 187 to $250mg{\cdot}L^{-1}$ for pak-choi.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.35-39
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• 2002

This study was conducted to investigate the effect of early $CO_2$ enrichment during seedling stage on long-term $CO_2$ enrichment after transplanting in the culture of pat-choi (Brassica campesris L), spinach (Spinacia oeracea L.), and leaf lettuce (Lactuca saliva L). During seedling stage, $CO_2$enrichment had significantly higher fresh and dry weight and leaf area of the top parts (above ground) of all three plant species than the control (no $CO_2$ enrichment). About 53%, 70% , and 40% increase in fresh weight of the top parts of pak-choi, spinach, and leaf lettuce were observed, respectively. Also, in seedling stage, dry weights of roots of spinach and leaf lettuce were significantly increased by early $CO_2$ enrichment. Relative fresh weight increment, compared with fresh weight of the control, in the top parts of roll three plants showed the highest values in 10 days after $CO_2$ enrichment treatment. In the long-term $CO_2$ enrichment experiment, early $CO_2$ enrichmented plants had 20% greater leaf area than the control in all three leafy vegetables. Fresh and dry weights of top parts of early $CO_2$-treated plants were also increased from 10 to 20%, as compared with the control plants. However, these increasement rates in the long-term $CO_2$ enrichment were lower than those seedling stage, which had 30-60% increment-rates. After transplanting, photosynthetic rate of each leafy vegetable in the control treatment slowly decreased, but those rates of early $CO_2$ enriched plants rapidly decreased.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.64-64
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• 2017

노지 고추 수확작업은 7~9월에 걸쳐 5~6회 수행되며 가장 더운 한 여름의 태양볕에 노출되어 장시간 수확작업을 하며 노지채소 및 고추 수확작업시 자외선 과다 노출되어 악성흑생종, 광선각화증, 편평세포 암 및 각종 피부암발생의 원인되기 때문에 적절한 해가림 장치의 설계가 필요하다. 해를 가려주는 장치에 사용되는 재질로는 우산 및 양산에 널리 사용되어지는 섬유로 폴리에스테르를 선정하였으며 두께로 우산의 재질로 많이 사용되는 75 denier을 채택하였다. 코팅의 종류로는 Foam, Milky, Silver, 폴리우레탄을 채택하여 섬유의 코팅 종류에 따른 차단 효과를 실험하였다. 실험 방법으로서는 KS K 0850 텍스타일의 자외선 차단율 및 차단지수 시험방법에 의거 하여 실험하였다. 자외선 UV-A(365n/m), UV-B(315n/m) 측정장치는 자외선 센서, UV램프, 인디케이터로 구성된 측정기를 이용하였으며 각 재료별 5회 반복 실시하여 평균치를 산출 하였다. UV-A(365n/m) 측정값으로는 FOAM, MILKY코팅이 된 섬유재질이 KS의 우산 및 양산품질표시기준에 부합하여 해가림 장치에 사용이 적절하였으며 UV-B(315n/m) 파장 차단율 측정값으로는 KS의 우산 및 양산품질표시기준에 모두 부합되었다. 또한 해가림 장치는 태양고도에 따라 각도를 조절 가능한 형태로 설계하였으며 직사광선이 가장 강한 시간대인 10시부터 12시를 기준하여 틸팅의 최대 각도는 20도로 개발하였다. 또한 바람에 의한 날림현상을 방지하고 통풍효과를 높이기 위해서 해가림 장치의 섬유를 2중 구조로 설계하여 바람의 순환이 되게하였다.