• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.9-13
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• 2008

The wasabi was planted in glasshouse to investigate the effect shade level (0, 10, 30, 70%) on growth and photosynthetic response. The net photosynthetic rate and stomatal conductance were the highest under 10% shading rate in greenhouse. The lowest transpiration rate was in the non-shading treatment. 70% shading rate significantly reduced in photosynthetic characteristics. The number of leaf was decreased with increasing of shading rate. Leaf and petiole weight was the highest 10% shading and then followed by the non-shading treatment. Number of leaves, leaf, petiole and total weight were severely declined in 70% shading treatment. Shading rate (0%, 10%, and 30%) did not significantly influenced on the leaf length, leaf width and root growth. 10% shading level was the most effective for wasabi leaf production in hydroponics.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.4
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• pp.1-13
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• 2022

This study was conducted to investigate the chlorophyll content, photosynthetic characteristics, and growth characteristics of Aster koraiensis and Dendranthema zawadskii var. latiloba according to shading treatment. A. koraiensis and D. zawadskii grew in four different shading treatment plots (0%, 50%, 75% and 95% of full sunlight) for experiments. It was found that as the shading level increased, the total chlorophyll content increased and dark respiration decreased in both A. koraiensis and D. zawadskii, indicating that A. koraiensis and D. zawadskii increase the utilization efficiency for photosynthesis under low light conditions. In addition, as the shading level increased, the net apparent quantum yield increased, resulting in the highest in the 95% shading plot, but the highest photosynthetic rate, water use efficiency, and leaf mass per area (LMA) were shown in the control group than in the shading treatments. The results showed that A. koraiensis and D. zawadskii are heliophytes showing plasticity to light, and if the light is restricted to continue to shade, it may be detrimental to growth. For healthy growth, it is considered suitable to grow A. koraiensis under full light conditions, and D. zawadskii under the light condition that blocks 0-50% of full sunlight.

• Korean Journal of Plant Resources
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• v.37 no.2
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• pp.203-213
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• 2024

In this study, we investigated the growth and physiological responses of Iris laevigata Fisch. to shading treatments in order to suggest optimal light conditions for ex-situ conservation of the northern lineage plants. For this purpose, a control plant receiving full sunlight and different shading treatments (50%, 75%, 95%) were installed, and leaf mass per area, chlorophyll content and fluorescence response, and photosynthetic characteristics were investigated. I. laevigata developed leaves with higher photosynthetic efficiency to adapt to lower light intensity as shading levels increased. Chlorophyll content increased with increasing shading levels, and leaf mass per area decreased with increasing leaf area. The chlorophyll fluorescence responses Fv/Fm and NPQ did not change with shading, and the activity of the carbon fixation system did not differ between treatments. I. laevigata exhibited a light-saturation point equivalent to that of sun plants and maintained photosynthetic capacity similar to that of controls up to 75% shading. The apparent quantum yield of I. laevigata decreased significantly at 95% shading, indicating adaptation to lower light conditions. It seems that the photosynthetic capacity of I. laevigata decreases when grown under 95% shading level compared to full sunlight, and it is judged that the longer the light is restricted by continuous shading, the more unfavorable the growth will be.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.22-22
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• 2020

너도개미자리는 석죽과의 다년생 초본류로 낭림산 이북으로부터 백두산까지 분포하며 고지대에 자생한다. 7~10월에 흰색의 꽃이 개화하고 종자는 달걀모양으로 표면은 밋밋하다. 본 연구는 지피용으로 사용할 너도개미자리의 분화재배 시 적정 추비, 차광 및 적심 등의 처리 정도를 알아보고자 수행하였다. 재배방법의 확립을 위하여 유용식물증식센터에서 종자를 분양받아 2019년 4월 19일에 트레이에 파종하여 충북대학교 유리온실에서 육묘한 유묘를 7월 4일에 정식하여 실험재료로 사용하였으며, 9월 24일까지 약 11주 동안 재배하였다. 공통 조건은 비닐 포트 3치(7×7cm)에 원예상토를 충진하고 200구 트레이에 셀당 1립씩 파종하여 생산된 1셀을 정식하였다. 추비, 차광, 적심 등은 무처리로 수행하였다. 추비실험은 hyponex 하이그레이드(N-P-K, 7-10-6)를 0, 500, 1000, 2000mg·L^-1의 농도로 엽면시비 하였고, 차광 실험은 0, 35, 55, 75% 차광막을 이용하였으며, 적심은 무적심과 재배 4주차의 1회적심 처리로 구분하였다. 연구의 결과, 너도개미자리는 추비처리 농도가 증가할수록 생육도 증가하는 경향이었으나, 유의성은 확인할 수 없었다. 유의적인 차이는 없었지만 2000mg·L^-1 처리구에서 지상부 및 지하부의 생체중이 가장 무거운 결과를 보였다. 차광처리 별로는 무차광 조건에서 생육이 왕성한 결과를 보였고, 차광률의 증가는 생육을 점차 억제하는 경향이었다. 개화율도 무차광에서 가장 높았으며, 다음으로 35% 차광 순이었고, 55와 75% 차광에서는 개화가 진행되지 않았다. 너도개미자리에 적심처리는 초장과 측지수의 발생을 억제하였고, 개화도 지연되는 경향을 보였다. 결론적으로 너도개미자리의 지피용 재배시 광이 충분한 에 배치하여 재배하는 것이 효과적이다. 추비는 Hyponex 하이그레이드를 2000mg·L^-1의 농도를 처리하는 것이 생육에 유리하며, 적심은 하지 않는 것이 효과적인 재배방법인 것으로 판단된다.

• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.152-156
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• 2007

The Condonopsis lanceolata Trautv. was planted in field to investigate the effect of afterwards shading in the condition of sun light of fifty six percent on the characteristics of photosynthesis according to leaf position at flowering stage. The vine length and leaf area were increased with shading treatment in comparison with that of non-shading. Dry weight of leaf and vine indicate opposite tendency with the result above. SLA (specific leaf area) was much more increased in shaded leaves than that obtained from non-shading treatment. The shaded leaves of plant show a higher SPAD value than that of non-shaded leaves. The net photosynthetic rate and stomatal conductance were increased as the PAR was increased. And it is the maximum valve (PAR of 700-1000 ${\mu}$mol/m$^2$/s of PAR) of all leaves. Overnurse and light saturation point of the Condonopsis lanceolata Trautv. shading-treated was improved in comparison with control as net photosynthetic rates of leaves positioned on each part of the stem was increased.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.230-236
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• 2021

Changes in greenhouse temperature and solar radiation due to fogging and shading were monitored during hydroponics in high temperature in summer season. Experiment 1 consists of four treatments, namely, Control, Shading, Fogging, and Fogging + Shading based on sunny days August. For Experiment 2, two melon cultivars of 'Dalgona' and 'Sopoong gaza' were cultivated in summer of 2020 using Fogging + Shading with the best result for temperature reduction effect from Experiment 1. As a result of Experiment 1, the effect of Fogging + Shading on temperature reduction was apparent where the inside was about 4℃ (as the lowest temperature) lower than the outside. Fogging + Shading showed the inside was 2-4℃ lower than the outside, and Fogging or Shading treatments had little difference, compared to the Control where the internal temperature of greenhouse was 3-4℃ higher than the external. For solar radiation changes between greenhouse inside and outside, the internal change was in a similar pattern between Fogging and Control, and between Shading and Fogging + Shading, respectively. In case of the Fogging treatment (similar with the Control) only the effect of solar radiation reduction as influenced by plastic greenhouse covering materials was examined. The Fogging + Shading had a very similar change in solar radiation to the Shading. Based on these results, Experiment 2 was conducted in summer of 2020 and resulted in a temperature reduction effect of about 3.9℃ according as the inside of air-conditioned greenhouse was kept 32.4℃ when the maximum temperature of the outside reached 36.3℃ in August during the cultivation period. In addition, the quality of melon fruit was good (1.3-1.5 kg of fruit weight, 12.6-13.3 of soluble solids content. In the case of using Fogging + Shading cooling treatment, it can bring about the effect of reducing the temperature during the high temperature in summer, and normal growth of melon and fruit harvesting were possible.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.479-485
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• 2002

This study was conducted in order to elucidate the effects of nitrogen level and split application method, and shading treatment during reproductive stage on sink formation. Japonica variety Choocheongbyeo and Hwaseongbyeo and indica$\times$japonica cross type variety Nampoongbyeo were used. Five levels (6 to 30 kg/10a at 6 kg/10a interval) of nitrogen fertilization, and two split application methods (50-25-25% and 30-30-40% as basaltillering-panicle fertilizer) for each nitrogen treatment were applied. In addition shading treatments (shading rate, 65%) were performed for N 12 kg/10a and 24 kg/10a plot. Shading were applied for 30 days from panicle initiation to heading, 15 days from panicle initiation and 15days before heading. Panicle per square meter, and primary rachis branches per panicle and differentiated number of secondary branch per panicle increased according as applied nitrogen amount increased up to 18 to 24 kg/10a, and there was no significant difference between two nitrogen application methods. Primary rachis branch and secondary branch per square meter also increased according as the amount of applied nitrogen increase up to 18 to 24 kg/10a, and there was no significant difference between nitrogen application methods. Panicle per square meter and primary rachis branch per panicle were significantly decreased due to shading treatments only in Choochengbyeo. In all varieties, shading reduced secondary rachis branch per panicle significantly and the reduction was greatest in 30 days shading during reproductive stage. Spikelets per square meter increased according as the amount of applied nitrogen increases up to 18 to 24kg/10a, but showed no move increase above this nitrogen application level. Significant difference was not shown between nitrogen split methods. Spikelets per square meter also decreased significantly due to shading treatment during reproductive stage, showing the greatest reduction by 30 days shading during reproductive stage, and the least by 15 days shading during booting stage. The variation of spikelets per square meter was influenced greatest by the variation of panicles per square meter and spikelets per secondary rachis branch.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1994.05a
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• pp.102-103
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• 1994

원예작물의 개화는 일장이나 생장조절제 처리 이외에도 광도, 관수량, 그리고 시비수준 등 재배환경에 따라 영향을 받는다. 차광처리는 광합성률을 낮추어 개화를 지연시키며, 관수처리는 건조시 양분흡수가 저해되거나, 수분부족 자체가 스트레스로 작용하여 종자생산을 촉진시키는 생식생장으로의 전환을 유도할 가능성도 있다. 쑥갓은 국내에서 엽채류로 4계절을 통해 많이 이용되나 개화생리에 대한 연구가 미비하다. (중략)

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.61-70
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• 1993

We investigated the effects of shading on the plant growth, flowering and the bulbil formation of Lilium species. As the shading treatment, we used full sunlight and various light intensity, 30%, 50%, 75%, 90% compared to full sunlight with shading net. The results obtained were as follows. The flowering rate and flower number of 'Roma' and 'Georgia' were not effected by various shading treatment. Days to flower in 'Roma' and Tiger lily showed similiar tendency like this. One of the shading effect was stem elongation of 'Connecticut king' markedly reduced compared with other cultivars in flowering rate and flower number. Leaf number of all cultivars was not consistent in tendency. But leaf number of Tiger lily and 'Connecticut king' reduced. The tendency of other experimented Lilium species weren't consistent. Bract leaf number reduced gradually as shading rate increased, plant height and internode length increased. Especially the height of 'Georgia' showed eminant increase compared with others. Total number and weight of bulbil of 'Enchantment' and Tiger lily reduced as shading rate increased.. But bulbil weight from bract part of 'Enchantment' in creased. The bulbils of 'Connecticut King' and 'Roma' appeared only on upper stem parts when treated serious shaded conditions, 75% and 90%. Only 'Connecticut King' and 'Enchantment' showed leaf emergence from bulbil among the L. elegans species.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.93-99
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• 2012

This study was conducted to investigate photosynthetic characteristics of two-year-old of Adenophora triphylla var. japonicum grown under control (full sunlight) and three different shading treatment (25, 50, and 75% shading treatment). Total chlorophyll contents like chlorophyll a and b content had not significant difference among treatments. Net photosynthetic rate of control and 25% treatment were higher than 50% and 75% treatment. Seedlings grown under full sunlight showed the highest photosynthetic activity such as photosynthetic rate, stomatal conductance and intercellular $CO_2$ concentration except for water use efficiency which was relative higher under 50% and 75% treatment.