• Title/Summary/Keyword: 광중단

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Effect of night break treatment using Red LED (660 nm) on flower bud initiation and growth characteristics of chrysanthemum cv. 'Baekma', and cv. 'Jinba' (적색 LED(660nm)의 광중단 처리에 따른 국화 '백마'와 '신마'의 화아분화 및 생육특성)

  • Kwon, Young Soon;Choi, Seong Youl;Kil, Mi Jung;You, Bong Sik;Jung, Jae A;Park, Sang Kun
    • Korean Journal of Agricultural Science
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    • v.40 no.4
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    • pp.297-303
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    • 2013
  • This study was carried out to examine the effect of Red LED (660 nm) and fluorescent lamp for night break (NB) treatments of each 3 hours (22:30-01:30), 4 hours (22:00-02:00) and 5 hours (21:30-:02:30) per day for 53 days on flower bud initiation and growth in Chrysanthemum cv. 'Baekma' and cv. 'Jinba'. The days to flower budding after short-day treatment in 'Baekma' was longer at fluorescent lamp 4 hr (21.0 days) and 5 hr (20.5 days) NB, and it was shorter at Red LED 3 hr (14.2 days). The days to flowering after short-day treatment in 'Baekma' was longer at fluorescent lamp 4 hr (54.0 days), 5 hr (53.5 days) NB, and Red LED 5 hr (53.3 days), and it was shortest at Red LED 3 hr (50.2 days) NB treatment among all treatments. The days to flower budding after short-day treatment of 'Jinba' was longer at fluorescent lamp 4 hr (20.6 days) and was shorter at Red LED 3 hr (14.1 days) among all treatments. Similarly, the days to flowering after short-day treatment of 'Jinba' was longer at fluorescent lamp 4 hr (55.3 days) and was shortest at Red LED 3 hr (50.2 days) among all treatments. Therefore, inhibition of flower bud initiation was the most effective under fluorescent lamp 4 hr treatment. The length of cut flower of 'Baekma' was increased by fluorescent lamp 4 hr, 5 hr, and Red LED 5 hr, but of 'Jinba' was longer at LED 4 hr and 5 hr treatment. The weight of cut flower of 'Baekma' was heaviest at fluorescent lamp 5 hr treatment and was at Red LED 5hr treatment for 'Jinba' even though there was not statistically significant difference between 'Baekma' and 'Jinba'. Consequently, under fluorescent lamp 4 hr for night break was the most effective on flower bud initiation, flowering inhibition and cut-flower characteristics in 'Baekma' and 'Jinba'.

Effects of Light Intensity, Nutrient Solution Compositions before Harvest and the Time of Nutrient Solution Removal on Nitrate Contents in Hydroponically-Grown Leaf Lettuces in Closed Plant Production System (폐쇄형 식물생산시스템에서 광도, 수확 전 양액조성 및 양액결제시기가 잎상추의 체내 질산염 함량에 미치는 영향)

  • Yeo, Kyung-Hwan;Choi, Gyeong-Lee;Lee, Jung-Sup;Lee, Jae-Han;Park, Kyoung-Sub;Kim, Jin-Hyun
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.393-401
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    • 2017
  • The nitrate ($NO_3{^-}$) accumulation of hydroponically grown leafy vegetables may increase in the condition of a closed-type plant production system with low light intensity due to low activity of enzymes involved in nitrogen assimilation and the use of $NO_3-N$ as major nitrogen source. The objective of this study is to investigate the effects of light intensities, nutrient solution compositions and the time of nutrient solution removal before harvest on nitrate contents of hydroponically-grown lettuces in a closed plant production system. The reduction of nitrate contents in leafy lettuces 'Cheongchima' was higher in the treatments of 'TW' (nutrient solution removal) and '$(NH_4)_2CO_3$' (use of ammonium carbonate as nitrogen source) than those in other treatments, which significantly lowered fresh weight and leaf area of the plants. In the light intensity of $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, the nitrate content was effectively reduced without causing any growth retardation, by substitution of the nutrient solution composition that $NO_3-N$ was removed ('$NO_3-N$ removal' treatment) or the half strength of standard nutrient solution was applied ('1/2 S' treatment), for 7days before harvest. The effects of light intensity and the time of nutrient solution removal before harvest on growth and nitrate contents in leafy lettuces were investigated. The nitrate contents in leaves under the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ before nutrient solution removal were lower than those of 100 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The removal of nutrient solution for 7 days before harvest quickly reduced the amount of nitrates in leaves in all the light intensities with a greater degree under the $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light condition, while the 7 days-removal with both 200 and $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light conditions caused decrease in 16~31% of leaf area and 20~35% of fresh weight, compared to the 3 days-removal treatment. The nitrate contents were greatly reduced from 3,018 to 1,035 in $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and 2,021 to 480 ppm in the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, with the nutrient solution removal for 3 days before harvest, without causing any deterioration in growth and product quality. The vitamin C contents in leaves were higher in the treatment of nutrient solution removal for both 3 and 5 days before harvest with the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ than those in the light condition of 100 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$.

Effects of Indoor Light Intensity on the Growth Characteristics of $Distylium$ $racemosum$, $Osmanthus$ $heterophyllus$ and $Damnacanthus$ $indicus$ (실내 광조건이 조록나무, 구골나무 및 호자나무의 생육에 미치는 영향)

  • Song, Eun-Young;Kim, Seong-Cheol;Chun, Seung-Jong;Lim, Chan-Kyu;Kim, Mi-Sun;Kim, Chun-Hwan;Ro, Na-Young
    • Journal of Bio-Environment Control
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    • v.21 no.1
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    • pp.66-73
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    • 2012
  • This study was conducted to develope new indoor plants and to investigate the effects of light intensity on the growth of $Distylium$ $racemosum$, $Osmanthus$ $heterophyllus$ and $Damnacanthus$ $indicus$ under 100 lux, 1,000 lux and 2,500 lux fluorescent lighting for six months in the environment-controlled growth chambers. 1. $Distylium$ $racemosum$ : Most of $Distylium$ $racemosum$ under 100 lux light intensity were blighted in two months, whereas it was 100% of survival under 1,000 lux and 2,500 lux after six months. Plant height, number of leaf, leaf width and leaf length became higher as light intensity increased. The plants maintained under 2,500 lux showed the greatest plant height and leaf number. 2. $Osmanthus$ $heterophyllus$ : $Osmanthus$ $heterophyllus$ under 100 lux light intensity were blighted in two months, whereas it was 100% of survival under 1,000 lux and 2,500 lux after six months. However, under 1,000 lux, it paused plant height and was not increased in leaf number any more. A plant growth status showed the highest value under 2,500 lux in all conditions. 3. $Damnacanthus$ $indicus$ : $Damnacanthus$ $indicus$ was defoliated and blighted under 100 lux light intensity in two months, whereas it was grown properly with 1,000 lux or above. However, the growth under 2,500 lux of $Damnacanthus$ $indicus$ was superior to other treatments. But, $Damnacanthus$ $indicus$ under 1,000 lux after 6 months was more favorable chlorophyll contents, leaf length and leaf width than 2,500 lux. As increasing slightly of chlorophyll contents and leaf growth under 1,000 lux, $Damnacanthus$ $indicus$ could be utilized highly to the indoor ornamental plant.

Changes in Subjective Discomfort, Blinking Rate, Lens Centration and the Light Transmittance of Lens Induced by Exceeding Use of Daily Disposable Circle Contact Lenses in Dry Eyes (일회용 써클소프트렌즈의 일일 초과착용 시 유발되는 건성안의 자각적 불편감, 순목횟수, 중심안정 및 렌즈 광투과율의 변화)

  • Park, Mijung;Kang, Shin Young;Chang, Jung Iee;Han, Arum;Kim, So Ra
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.2
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    • pp.153-162
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    • 2014
  • Purpose: This study was assessed to investigate the change of subjective and/or objective symptoms and the light transmittance of lens caused by the use longer than recommended wearing time of daily disposable circle contact lenses (circle lens) in dry eyes. Methods: Three daily disposable circle lenses made of etafilcon A, hilafilcon B, and nelfilcon A were applied on 30 dry eyes with smaller tear volume than normal eyes in their twenties free from any eye diseases by when subjects complained any kind of discomfort. On the first and the last days of lens wearing, subjective discomfort, blinking rate, lens centration on corneal surface and visible light transmittance of lens were recorded at every case and compared. Results: The circle lens wearers complained subjective discomfort and quit the lens wearing when they wore the circle lens longer than 10 hours even though there were some difference according to the lens materials of daily disposable circle lens. However, around 20% of dry eyes could wear the circle lens made of non-ionic materials longer than 40 hours. Dry eyes showed most sensitive feeling of subjective discomfort against the circle lens made of etafilcon A among three different lens materials. On the last day of lens wearing, the representative subjective discomforts were irritation, stiffness, dryness and tiredness. When the subjects wore circle lens more than the recommended time, blinking rate was significantly increased about 20~30% regardless of lens materials when it compared with the values right after lens wearing. On the last day of lens wearing, the vertical direction of lens centration was shifted to pupil center however, its distribution in horizontal direction was wide compared with the distribution right after lens wearing. Especially, the centration of etafilcon A lens was unstable. Furthermore, the visible light transmittance of 3 different circle lenses in dry eyes has significantly been reduced around 15% averaged. Conclusions: From these results, it was known that the increase of dryness and stiffness caused by overusage of daily disposable circle lens induced excess irritation and decreased visible light transmittance and caused significant more blinking, which provoked lens decentration. It was also revealed that dry eyes showed sensitive reaction subjectively and objectively against the overusage of circle lens made of high water content/ionic lens material even there were some difference of the degree depending on the individual and the lens material. Thus, this research can be suggested as the basic reference for the education about some unexpected problems and the side effect caused by the wearing of circle lens in dry eyes.

Chemical burns of the oral mucosa caused by Policresulen: report of a case (Policresulen 오용에 의한 구강 궤양의 발병 증례 및 화학화상에 대한 고찰)

  • Jung, Jung-Woo;Byun, Jin-Seok;Jung, Jae-Kwang;Choi, Jae-Kap
    • Journal of Oral Medicine and Pain
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    • v.38 no.2
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    • pp.109-114
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    • 2013
  • Chemical burn on the oral mucosa is caused by contact with various chemical products and manifests with localized mucositis, keratotic white lesions, bleeding, and painful tissue surface due to the coagulation of the tissue. Policresulen ($Albothyl^{(R)}$) is a topical antiseptic, commonly used over-the-counter drug for vaginitis, thrush and stomatitis. This drug is highly acidic with pH 0.6, and can act as a strong corrosive agent to oral mucosa. When inadvertently used in oral cavity, it may cause chemical burns of oral mucosa, resulting necrosis and bleeding surface resembling to erythema multifome. A 56 years old female patient presented with the chief complaints of painful ulcerations on the tongue, the upper and lower lips. On intraoral examination, an erythromatous, erosive or ulcerative surface covered with inflammatory exudates or bleeding crust is observed on the anterior half of the tongue and the upper and lower lips. She has occasionally applied the policresulen solution topically on the tongue to relieve pain from recurrent focal glossitis for about 10 years. In this time she applied it broadly and repeatedly to the tongue, the upper and lower lips for the purpose of pain relief by herself without instruction by physician or dentist. After cessation of policresulen application, the oral mucosa was rapidly recovered with use of topical steroids. In 2 weeks the lesions subsided completely. In summary, inadvertent use of $Albothyl^{(R)}$ on oral mucosa may result in chemical burn, causing mucosal erosion, ulceration and inflammation. It can be recovered by topical use of corticosteroid for 2 weeks after cessation of using $Albothyl^{(R)}$.

A Study on Nam Nyeong-wie Yun Uiseon's Gwanbok Described in the List of Wedding Gifts in 1837 (남녕위(南寧尉) 윤의선(尹宜善)의 1837년 「혼수발기」 속 관복(冠服) 고찰)

  • Lee, Eunjoo
    • Korean Journal of Heritage: History & Science
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    • v.52 no.3
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    • pp.200-221
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    • 2019
  • The National Hangeul Museum houses a document list of the wedding gifts that Queen Sunwon granted her royal son-in-law, Nam Nyeong-wie, in August 1837. A total of 55 items were recorded in Hangeul Gungseo style on yellow paper. This list included four types of government officials' uniforms, casual wear, accessories, etc. The results of studying the 19th-century male officials' uniforms through this historic record were as follows. The clothing record in the List of Wedding Gifts was more accurate than that in the Dukongongju Garyedeungrok. The four types of government official uniforms for Nam Nyeong-wie included jeobok, sangbok, sibok, and gongbok. For the joebok, there was geumkwan, daehong-hangrah joebok, baeksam, ahole, seodae, gakpae, peseul, paeok, husu, and mokhwa. The record of the List confirms that baeksam was used as jungdan for joebok. For the gongbok, there was daehong-hangrah gongbok, blue seolhancho duhgre, blue saenggyeonggwangju changui, and green waehangrah kurimae. The record of the List shows that the lining of the gongbok was duhgre, and confirms, for the first time, that changui and kurimae were worn inside the gongbok. For the sangbok, there was samo, ssanghakhyungbae embroidered with golden thread, dark green cloud patterned gapsa gwandae, blue cloud patterned gapsa duhgre, blue ssangmuncho changui, and Chinese purple hwamunsa kurimae. For the sibok, there was pink gwangsa gwandae, and blue gwangcho duhgre. For the lining, blue duhgre was used. Lastly, the fabrics used for those costumes were all suitable for the climate in August.

Effects of Environmental Factors on Growth and Nitrogen Fixation Activity of Autumn Olive (Elaeognus umbellata) Seedlings (보리수나무 유식물의 생장과 질소고정 활성에 대한 환경요인의 영향)

  • 송승달
    • Journal of Plant Biology
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    • v.37 no.3
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    • pp.387-394
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    • 1994
  • Effects of environmental factors of light, temperature, nitrogen sources and water stress were analyzed quantitatively on the nodule formation and nitrogen fixation activity of autumn olive plant (Elaeagnu$ umbellala Thunb.) during the seedling growth. Seedlings showed the maximum nitrogenase activity of $72.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ in the early nodulation stage. The relative growth rate and T/R ratio changed from $1.60%{\cdot}d^{-1}$ and 1.12 in the earlier stage to $3.75%{\cdot}d^{-1}$ and 2.31 in the later stage, respectively. light conditions of 20-25, 1015 and 4-6% resulted in decreases of 41, 54 and 71% of the nitrogenase activity, respectively. Nodules incubated in 15, 20, 25 and $30^{\circ}C$ showed the activities of 5.4, 24.7, 51.6 and $58.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ respectively. Pretreatment with low temperature ($15^{\circ}C$) followed incubation at $30^{\circ}C$ attained higher nitrogenase activity ($66.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$) than that with higher temperature ($35^{\circ}C$). The oxygen pressure above 16 kPa is necessary for saturation of the nodule activity, but the activity was inhibited severely by physical impact such as the exision or isolation of nodules from the root. The relative activities of early nodules grown in pH 5.5, 6.5 and 8.0 were 89, 100 and 40% and those grown in 1 and 3 mM of $NO_3\;and\;NH_4$ were 6, 1 and 68, 50%, respectively. Watering levels of 20, 50 and 100 mL during the seedling growth resulted in 35, 120 and 8 mg of nodule formation and 33.6, 58.4 and $8.4\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ of the nitrogenase activity, respectively. Water stress with 86% decrease of soil water content caused temporary wilting point of leaf and a complete disappearance of nitrogenase activity of nodules, though the water content and transpiration rate in plant were reduced to 90 and 53%, respectively.tively.

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