• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.455-463
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• 1996

Studies were carried out to determine the effect of sulfur dioxide on leaf injury and yield of ten soybean cultivars. Plants were fumigated with 2.0 ppm of $SO_2$ for 4 or 8 h in a closed-top field chamber. In the comparison of foliar injury, Paldalkong and Eunhakong were more susceptible to $SO_2$ than Bogwangkong, Jangsukong, and Jangkeungkong. Correlations between chlorophyll contents, peroxidase activity, and stomatal resistance of leaves and foliar susceptibility were insignificant. However, significant correlations $(r=-0.611^{\ast})$ were found between superoxide dismutase activity and foliar injury rates. Dry weight, number of pods and total grains were significantly reduced by $SO_2$ fumigation but plant height, number of nods and weight of 100 grains were not affected. Yield reduction rates were higher in Eunhakong and Paldalkong than in Bogwangkong and Jangkeungkong. A liniar relationship was found between foliar injury rate and the percent crop loss with a significant coefficient of b=-1.17 in the susceptible cultivar of Paldalkong, but Bogwangkong, insusceptible cultivar, showed lower value of -0.165.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.158-165
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• 2018

The effects of different kinds of supplementary lighting or heating lamps on the yield, cut flower life, and leaf color of cut rose were compared and analyzed. For this purpose, light emitting diode lamp (LED), metal halide lamps (MH), and high-pressure sodium lamps (HPS) as the supplementary lamps, and carbon fiber infrared lamp (NCFI) were installed on hydroponic cultivation bed in a cut rose farm. The yield of cut flower rose and the number of marketable flowers were greatly increased in spring and autumn by HPS treatment, but not in winter. The length of flower stalk was longer than that of control in the spring but decreased in winter. It seemed likely that the shorter flower stalk in winter was due to the shortened period of vegetative growth compared to the control because flowering was promoted by supplementary lighting. Vase life was not different among treatments in the autumn when the lighting time was short, but in winter, it was prolonged to 3 more days by only HPS, compared with the control. Leaf color was significantly affected by light treatment in winter rather than autumn. Leaf color was darkened in all supplementary lamps (LED, MH, HPS) treatment, whereas NCFI was similar to the control in leaf color. In conclusion, HPS is considered to be a very good supplementary lamp because it increases the length of flower stalk and the yield and prolongs vase life in cut roses. Even though NCFI could function as a heating lamp radiating a lot of heat, it was considered that the role as a supplementary light is unsatisfactory because the number of marketable flowers decreases and the quality index of cut rose deteriorates by NCFI.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.178-180
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• 2006

광은 식물의 광합성 작용뿐만 아니라 조직이나 기관의 분화, 종자의 발달 등 식물의 형태형성에도 관여하는 중요한 요인 중 하나이다. 불량한 광환경조건 하에서는 작물의 생육부진 뿐만 아니라 다양한 생리장해 및 병발생 등을 유발하기 때문에 경제적으로 광효율을 증가시키기 위하여 적절한 시설구조를 채택해야 한다. 또한 작물의 생육과 품질을 향상시키기 위하여 보광 및 차광 등 광환경 관리기술 개발이 요구된다. 본 연구에서 도입한 적외선램프는 새로운 인공광원으로서 태양광과 80% 정도 유사하고 용도에 따라 근적외선, 중적외선 및 원적외선이 방사되도록 할 수 있으며, 적은 전력소모량과 발생되는 열원은 겨울철 온풍난방기를 보조하거나 대체할 수 있어 에너지 절감효과를 동시에 기대할 수 있다. 따라서 본 연구는 인공광원에 대한 기초연구로서 인공광원의 종류별 분광특성을 비교 분석하고, 일몰 후 적외선램프의 조사 시간이 배추와 상추 유묘의 생장에 미치는 영향을 구명하고자 실시하였다.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.294-301
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• 2016

This study was conducted to analyze the seedling quality of korean melon and the growth after transplanting of korean melon nursed under the LED sources. LED sources were RB7 (Red:Blue=14:2), RB3 (Red:Blue=12:4) and Blue(B=16). Photosynthetic photon flux density(PPFD) was 50, 100 and $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The lighting treatment was started after graft-taken and was applied for 20 days at 4 hours(05:30 and 07:30, 17:30 and 19:30) per day. Plant height and stem diameter of scion were longer and thicker under a high ratio of blue light condition. Dry matter ratio and compactness were highest in RB3 compared to the other LED sources treatments. $CO_2$ exchange rate increased $5.44{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$ under RB7 $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and dropped to negative values under control. PPFD $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of RB3 resulted in the longest plant height by 132.3cm and flowering ratio also was the highest by 75%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.2
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• pp.128-133
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• 2003

Stimulus effects of strobe light on jack mackerel Trachurus japonicus were studied by measuring the heart rate change according to the different strobe light intensity of 5~75 lx$\cdot$s. Heart rate was observed for 60 min: 10 min before, 30 min during and 20 min after the strobe light stimulus. The measurement of heart rate was repeated three times at 2 hour intervals. The results showed that the heart rate increased during stimulus but temporarily decreased immediately after ending of stimulus. The heart rate changes in both during and after stimulus were decreased with reducing light intensities. The heart rate change according to the repeated experiment was not remarkably different under the lower light intensity

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.182-188
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• 2011

This research was conducted to evaluate the effect of supplemental light-emitting diode (LED) light on growth characteristics and phytochemical content of pepper (Capsicum annuum L.) seedling using LED blue (470 nm, B), red (660 nm, R), blue + red (BR), far red (740 nm, FR) and UV-B (300 nm) light treatment, and without artificial light. Photon flux of LED light was 49, 16, 40, 5.0 and $0.82{\mu}mol\;m^{-2}s^{-1}$ for B, R, BR, FR, and UV-B light, respectively, during experiment. Supplemental LED light duration was $16hr\;day^{-1}$ and UV-B light duration was 10 min. per day after sunset up to 15 days (12 days after germination) of plants age. In our research, growth characteristics and phytochemical content of pepper seedlings were greatly influenced by supplemental LED light compare to control treatment. Red light increased the number of leaves, number of nodes, leaf width and plant fresh weight by 34%, 27%, 50% and 40%, respectively. Blue light increased the leaf length by 13%, and stem length and length of inter node were increased by 17% and 34%, respectively under grown far red light. After 15 days of light treatments phytochemical concentrations of pepper plants were significantly changed. Blue light enhanced the total anthocyanin and chlorophyll concentration by 6 times and 2 times, respectively. Red light increased the total phenolic compound at least two folds meanwhile far red light reduced the ascorbic acid and antioxidant activity 31% and 66%, respectively compared to control treatment.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.237-243
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• 2021

The objective of this study was to evaluate the effect of stem number on plant growth, fruit quality, and yield of sweet peppers grown in greenhouses under supplemental lighting in winter. The seedlings were transplanted at 3.2 plants·m^-2 on October 26, 2020, and started supplemental lighting with 32 high pressure sodium lamps for 16-hour photoperiod from December 1, 2020 to May 25, 2021. Stems were differently trained with 2 and 3 numbers after branching nodes were developed. In the final harvest, the plant height was significantly shorter in the 3 stem-plants than in the 2 stem-plants. The number of nodes per stem and the leaves per plant were increased in the 3 stem-plants than in the 2 stem-plants, while the leaf area was less affected. There were no significant differences in the dry mass of leaves, stems, and immature fruits between the 2 and 3 stem-plants. The fruit fresh weight and fruit dry weight in the 3 stem-plants were decreased by 17% and 12% at 156 days after transplanting (DAT), and by 17% and 15% at 198 DAT compared to those in the 2 stem-plants, respectively. The marketable fruit rates were 93.6% and 95.4% in the 2 and 3 stem-plants, respectively. The total fruit yield in the 3 stem-plants was increased by 30.2% as compared to that in the 2 stem-plants. We concluded that the 3-stem-training cultivation positively affected the total fruit yield by sustaining adaptive vegetative growth of the plants. This result will help producers make useful decisions for increasing productivity of sweet peppers in greenhouses.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.301-306
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• 2020

The vertical garden is an environment where plants have many limitations in their growth. In particular, the upper and lower parts of the foundation are characterized by unbalanced moisture distribution. And although it may vary depending on the installation location of the light, generally the base of the light is not in desperate need for plants to grow due to shade. The purpose of this study was to identify the physical characteristics of the vertical garden based on Felt through experiments, classify the location characteristics of the media, and suggest the method of installing the water quantity water frequency, and lighting according to the location characteristics of the foundation. As a result, it was found to be most appropriate to use a 4mm base for the vertical garden and to have an irrigation of about 10 minutes once every 6 hours. In addition, it was found that in order to create a light condition for sufficient growth of plants, light bulbs should be installed at the upper and lower parts of the foundation. As a result of irrigation and lighting tests, the results of the above-mentioned plants need to be referred to in selecting plants that are introduced to vertical gardens, as the results show that the upper part of the foundation has a lower moisture rate and a stronger light than the lower part, and the lower part has a higher moisture rate and a weaker light than the upper part. In the future, we would like to present more accurate methods of selecting and maintaining plants by conducting plant experiments using the underlying characteristics found in this study.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.415-423
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• 2018

The aim of this study was to evaluate the individual glucosinolate (GSL), total phenol, total flavonoid, and vitamin C content, and antioxidant activity under various light quality condition, mainly focusing on red (R) to far-red (FR) light ratios in three Brassica sprouts (radish, Chinese cabbage, and broccoli). Three R/FR ratio of 0.6, 1.3, and 2.0 were exposed to 5-day old sprouts for 48 h in a controlled environment, and the targeted phytochemical contents and antioxidant activities were compared with three separate control plot of dark, fluorescent, and red:blue 8:2 conditions. Total GSL content was highest in broccoli among the cultivars throughout the respective treatments, and increased with the increasing of R/FR ratio in the broccoli sprouts, while the content showed non-significant results in the Chinese cabbage sprouts. The progoitrin, a major GSL in Chinese Cabbage and broccoli, content decreased by upto 38% and 69%, respectively, with decreasing the R/FR ratio compared to the control plots (fluorescent, red:blue 8:2, and dark condition). The contents of phenol, flavonoid, and vitamin C were lowest in dark condition in all the three Brassica sprouts. The total phenol content and antioxidant activities increased with decreasing the R/FR ratio in all the Brassica sprouts, while total flavonoid and vitamin C content showed different patterns depending upon the Brassica sprouts. These results suggest that additional use of FR is expected to improve the functional quality of Brassica sprouts in different ways.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.197-203
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• 2021

Saponarin is a crucial component of barley sprout, and the production and quantitative analysis are issued to date. In this study, the optimal saponarin extraction conditions were presented on the subject of acetonitrile, ethanol, methanol, and water for the quantitative analysis in barley sprout through the extraction efficiency compared with the solvent concentration and extraction time using the reaction surface methodology. The optimal extraction time and solvent condition for saponarin were 3.9 h and 53.7% of aqueous methanol, respectively. In addition, the effect of LED artificial light on the saponarin production in barley sprouts was evaluated by the light cycle, light quantity, and light quality. The optimal cultivation conditions under artificial light for the growth of barley sprout and saponarin production were most effectively achieved on 220-320 μmol m^-2 s^-1 of the light quantity with 8 h day^-1 of a daylight cycle under 6500K LED combined with red light. Furthermore, blue light was evaluated as the main factor in the biosynthesis of saponarin.