• 한국환경과학회지
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• 제28권11호
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• pp.1019-1025
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• 2019

The aim of this study was to analyze the light traits in a solar light-collector device and its effects on lettuce growth at an early growth stage. The three hyper parameters used were the reflector diameter (2 cm and 4 cm), coating inside the reflector (chrome-coated, non-coated) and distance from the light fiber (15 cm and 20 cm). The results showed that light efficiency, which is the ratio of light intensity inside the fiber to the solar intensity, improved by 41.1 % when using a 2 cm diameter chrome-coated reflector at a distance of 15 cm from the light fiber; whereas it only improved by 20.6% when a non-coated reflector was used. As the reflector size was increased to 4 cm, the light efficiency for the coated and non-coated reflectors increased by 28.5 % and 26.4 %, respectively, hence, no significant difference was observed. When the light fiber was placed at a distance of 20 cm, the increase in light efficiency with coating treatment was 8 % higher than without coating treatment. We also compared the efficiency of light-fiber treatment with that of LED treatment in our lettuce nursery, and observed that the plants exhibited better growth with light-fiber treatment. We observed an average increase of 1.7 cm in leaf height, $7cm^2/plant$ increase in leaf area, and 32 mm increase in root length upon light-fiber treatment as opposed to those observed with LED treatment. These findings indicate that the collector light-fiber is economically feasible and it improves lettuce growth compared with the LED treatment.

• Journal of Photoscience
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• 제5권4호
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• pp.157-162
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• 1998

The effect of heat treatment in the light on the subsequent CO2 fixation was studied with isolated spinach chloroplasts to define the role of light during heat stress. The degree of inhibition in CO2 fixation after heat treatment at 35$^{\circ}C$ under full light intensity (600W/$m^2$) was same as that in the dark. However, heat treatment of isolated chloroplasts in the light manifested thylakoidal damage, which did not occur in the dark. Under weak light (10~30 W/$m^2$ ) where no thylakoidal damage occurred, the inhibition was substantially alleviated , showing protective effect of light . The inhibition caused by heat treatment in the dark or light is prevented by the addition of a few combined compounds to the medium prior to treatment. Fructose-1-6- bisphosphate(with aldolase)and ribose-5-phosphate, known to be effective combined with oxaloacetate in preventing inhibition after heat treatment in the dark were equally effective in the light even without oxaloacetate. Addition of sugar phosphate reduced the Mehler reaction, which may occur in fast rae under high light. However, the addition of bicarbnate and catalase that would remove Mehler reaction did not provide any protection, indicating that protective role of sugar phosphate is elsewhere. Furghermore, in whole plants rapid recovery from heat stress was observed in the light. The apparently lesser or equal inhibition in spite of additional thylakoidal damage under heat stres in the light and less requirement for the protection against heat treatment suggest that the inhibitory effect of heat stress is alleviated by light treatment.

• 생명과학회지
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• 제11권2호
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.

• 한국작물학회지
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• 제48권1호
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• pp.13-16
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• 2003

Seeds of burcucumber were treated with accelerated aging, cold-stratification, and light quality illuminated during desiccation to enhance their germination and seedling emergence. The germination was increased by aging and cold-stratification although the latter treatment showed greater effectiveness than the former one. In the combined treatment of aging 6 days at $45^{\circ}C$ and cold-stratification, the germination was promoted under longer period of cold-stratification to reach nearly 100% in 3 week cold-stratification on the ninth day from sowing. In the sequentially combined treatment of aging, cold-stratification, and light quality during 24 hour desiccation at $35^{\circ}C$, no-stratified seeds showed the highest rate in red light treatment but the lowest in far-red light. This implies that the phytochrome action run during the desiccation of imbibed seeds. The red light exposure during drying for the cold-stratified seeds after aging accelerated the germination even more than the dark treatment and germinated 100% on the next day of sowing. It is concluded that the sequential treatment of aging, cold-stratification, and red light illumination during desiccation can highly promote percentage and speed of burcucumber seed germination.

• 한국환경과학회지
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• 제33권5호
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• pp.305-322
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• 2024

The aim of this study was to investigate the effects of artificial light sources on the germination and seedling vigor of lettuce, aiming to identify the optimal artificial light source for producing high-quality seedlings. Lettuce cultivar of 'Tomalin' and 'Seonpunggold' exhibited the highest seed emergence in the Metal halide(MH) lamp and High-pressure sodium(HPS) lamp treatment group, while the emergence rate parameter, T50, was the fastest in the HPS lamp treatment group. Both cultivars showed good growth characteristics such as number of leaves, root length, and stem diameter under RGB-LED, and their seedling vigor was excellent as well. The plant height was smallest in the Red + Green + Blue LED treatment, but the leaves were round and thick, resulting in higher biomass and dry weight. Single light sources of Red LED and Blue LED led to reduced growth compared with that under the mixed light treatments. Chlorophyll content in lettuce varied with the type of artificial light, with both cultivars exhibiting the highest chlorophyll content in the Red + Green + Blue LED treatment. The most suitable artificial light for lettuce seedling growth was the Red + Green + Blue LED treatment.

• 한국작물학회지
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• 제48권6호
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• pp.460-464
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• 2003

본 연구는 벼 종자의 파종 후 발아, 유묘출현 및 생육 초기에 가하여지는 광질처리가 유묘 출현, 생장, 형태, 엽록소 함량 및 광합성율에 미치는 영향을 조사하여 벼의 육묘에 이용되고 있는 부직포의 색상을 전환할 필요가 있는가를 검토하고자 실시하였으며 그 결과를 요약하면 다음과 같다. 1. 파종 직후에 가하여지는 광질처리에서 유묘출현율은 조사일 모두 일미벼에서는 광질처리간 차이가 없었다. 그러나 동진벼와 대산벼에서는 원적색광 처리에서 가장 낮았으며, 청색광과 적색광간에는 차이가 거의 없었다. 2. 파종 직후에 가하여지는 광질처리로 인하여 원적색광 처리에서 초장과 엽장이 가장 짧았던 반면, 적색광은 뿌리수를 증대시켰다. 3. 파종 직후에 가하여지는 광질처리로부터 지상부 건물중은 청색광 처리에서, 뿌리의 건물중은 적색광 처리에서 가장 많았던 반면, 지상부 및 뿌리 건물중 모두 원적색광에서 가장 적었다. 4. 엽록소 함량과 광합성율 모두 품종간에는 일정한 경향이 없었으나, 광질처리에서는 이들 모두 적색광에서 가장 높고, 청색광, 원적색광 순으로 감소하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.217-217
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• 2017

Seed priming leading to improved emergences, germination speed and uniformity under unfavorable conditions without loss of longevity are the best level of techniques. We studied the possibility to obtain primed seed with reduced mean germination time (MGT) and uniformity but with simple, fast and effective methods. The experiments were carried out at $15^{\circ}C$ for 16 hours with priming treatment. To compare the effects of each treatment, we used 200mM $CaCl_2$ priming or hydro priming or no imbibition after ultrasonication or red light treatment. The light treatment was performed by irradiating 2000 lux of red light for 15, 30, 60, and 120 minutes. Addition, in order to investigate the effect of the priming solution, treated at 200mM $CaCl_2$ for 8 hours. Ultrasonication treatment was performed for 5, 10, and 20 minutes at exposures of 13.0, 17.3, and 21.6 kHz during priming. For liquid smoke (LS) treatment, seed soaked in 0%, 0.5%, 1.0%, 5.0% and 10.0% of diluted water and 200mM $CaCl_2$ solution. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$ for 24 hours. The effect of seed treatment was evaluated with germination percentage (GP), MGT, germination index(GI), germination rate(GR), Germination Uniformity(GU) and heath seed percentage(HS). For several factors tested, we found that the desired germination improvement could be obtained by treating the seed with ultrasonication at 17.3 kHz for 5 minutes in water or red light exposure at 2000 lux for 120 min in water that resulted very similar to those used to 200mM $CaCl_2$ priming for 16 hrs. However, LS treatment showed no improvement in all diluted solution. Therefore, the methods applied ultrasonication and red light treatment showed high potential for fast and easy treatment avoiding pollution of salt solution waste.

• 한국작물학회지
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• 제42권4호
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• pp.384-391
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• 1997

산형과 약용작물인 시호의 재배에서 나타나는 문제점의 하나는 발아 불량에 의한 입묘 실패라할 수 있다. 따라서 파종 전 종자에 손쉽게 처리할 수 있는 방법을 모색하여 입묘율을 증진할 수 있는가에 대한 정보를 얻고자 재래시호와 최근에 육성된 장수시호를 공시하여 치상 전의 $GA_3$ 처리 [0(물), 0.01, 0.1mM (농도) : 2, 4, 8일 (기간)] 또는 저온처리기간 (0, 4, 8주)에 가하여지는 광질처리 (적색광, 백색광, 암)가 발아율에 미치는 영향을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. 요인별 평균 발아율은 공시품종, GA$_3$ 침지기간 또는 광질처리에 의하여 영향을 받는 것으로 분석되었던 반면, 물과 $GA_3$ 처리 또는 $GA_3$ 처리농도간에는 차이가 없었다. 2. 물로 침지하면서 광질처리를 가할 경우 평균발아율은 장수시호보다 재래시호에서 높았고, 2~4일간 침지하거나 침지과정 중 적색광을 처리할 경우 발아가 향상ㆍ촉진되는 경향을 보였다. 3. 공시품종별 발아율에서 재래시호는 광질처리간에 차이가 없었으나, 2일간 물로 침지하면서 광질처리를 가할 경우 발아율이 가장 높았던 반면, 장수시호는 4일간 침지하면서 적색광을 가할 경우 가장 높았다. 4. 치상 전 저온처리를 가하지 않는 상태에서 광질처리를 할 경우 발아율이 가장 높았으며 발아과정에서는 암상태보다는 백색광에서 발아율이 향상되었다. 5. 저온처리를 가하지 않은 경우 평균 발아율은 광질처리간 차이가 없고, 장수시호보다는 재래시호에서 높다고 할지라도 장수시호는 2일간 물에 침지시킨 후 발아과정에서 빛이 있어야 발아율이 향상될 것으로 보인다.

• 한국식품과학회지
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• 제11권3호
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• pp.162-165
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• 1979

신미종(辛味種) 고추인 가락금장 2호를 공시(共試) 품종(品種)으로 하여 추숙(追熟) 시(時)에 red 광(光)을 처리(處理)하여 white 광(光)에 대(對)한 적변(赤變) 효과와 주요(主要) 성분(成分)에 미치는 광질(光質)의 영향(影響)을 조사(調査)하였다. 추숙용(追熟用) 녹숙(綠熟) 고추는 개화(開花) $30{\sim}35$일(日) 정도의 것을 사용(使用)하였고, 이때 실험(實驗)은 $25^{\circ}C$ 항온(恒溫)에서 행(行)하였으며, 약(約) $40\;{\mu}watt/cm^2{\cdot}sec$에너지 수준의 광(光) 처리(處理)를 1일(日) 12시간(時間) 하였다. 광(光) 처리(處理)에 의(依)한 chlorophyll의 감소(減少) 현상(現狀)은 blue 광하(光下)에서 뚜렷하였고, red 광구(光區)는 white 광구(光區)와 차이(差異)가 없었으며, chlorophyll a와 b도 blue 광(光)에 의한 total chlorophyll의 감소(減少) 현상(現狀)과 동일(同一)한 경향을 나타내었다. Total carotenoid는 blue 광(光) 처리구(處理區)에서 생성(生成)이 촉진되었고 (약(約) 31%), 착색도(着色度)(color score)와 chlorophyll의 영향(影響)과는 달리 대조구(對照區)인 white 광구(光區)에 비(比)하여 red 광(光) 처리구(處理區)에서 함량(含量)이 적었다. 그러나 ${\beta}-carotene$은 red 광(光)의 효과는 없었고, blue 광구(光區)에서 0.71 mg%-f.w.로 white 구(區)의 0.56 mg%-f.w.에 비(比)하여 많았다. 따라서 추숙(追熟) 시(時) 착색(着色) 효과는 blue 광하(光下)에서 현저하게 나타났다. 신미(辛味) 성분(成分)(capsaicin) 역시 red 광(光)의 효과를 인정(認定)할 수 없었고 다만 blue 광하(光下)에서 다소 많았다.

• Membrane and Water Treatment
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• 제10권3호
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• pp.191-199
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• 2019

In this study, we investigated the cultivation possibility using Hydrodictyon reticulatum in a continuous raceway pond as a tertiary sewage treatment plant. The cultivation possibility was evaluated by varying the light quantity, wavelength, and hydraulic retention time (HRT). Experimental results showed that the growth rates of algae and the removal efficiencies of nutrients increased as the light quantity increased, and the maximum photosynthetic rate was maintained at $100{\mu}mol/m^2{\cdot}s$ or higher. When wavelength was varied, nutrient removal efficiency and growth rate increased in the following order: green light, red light, white light, and blue light. The nutrient removal efficiencies and algae productivity in HRT 4 d were better than in HRT 8 d. We conclude that if Hydrodictyon reticulatum is cultivated in a raceway pond and used as a tertiary treatment facility in a sewage treatment plant, nutrients can be effectively removed, and production costs can be reduced.