• The Korean Journal of Ecology
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• v.26 no.6
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• pp.321-326
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• 2003

This study was conducted to investigate and effects of shading treatment on photosynthetic activity of Acanthopanax senticosus. We investigated plant growth, light response curve and A-Ci curve to photosynthesis of A. senticosus at 55%, 75%, and 90% shading treatment. As results, the ratio of above-ground/under-ground biomass was increased at 75% shaded condition and showed highest dry biomass. Under shaded conditions, plants had lower chlorophyll a+b content and a/b ratio and also showed thinner leave. But shaded plants showed higher leaf area and higher total leaf area per a plant. This apparently indicates adapted responses to shaded treatment. Effects of shading treatments on photosynthetic activity were higher in apparent quantum yield, carboxylation efficiency, re-phosphrylation but lower in light compensation point. These results suggested that higher photosynthesis rates in shaded treatments were due to activated carboxylation efficiency. Shading treatment had lower water use efficiency thatn controls but still higher than other tree species.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.403-408
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• 2010

This study was carried out to investigate the physiological responses of $Rhododendron$ $mucronulatum$ Turcz. and $R.$ $indicum$ (L.) Sweet seedlings with 0%, 35%, 55% and 75% shading of full sunlight in polyethylene film house. The shading treatments were performed during the late growth season for each species (from Sept. 9 to Nov. 5, 2008). The shading treatment was effective in reducing the daily temperature by 0.9 to $1.7^{\circ}C$ during September and by 0.8 to $1.7^{\circ}C$ during October. Before the shading treatments, the water content of $R.$ $mucronulatum$ and $R.$ $indicum$ amounted to 68.5% and 66.3%, respectively. The water contents of two species after 75% shading treatment period decreased to 66.2% (3.4% reduction) and 65.9% (0.6% reduction), respectively. Notably, both species had a similar tendency indicating less reduction rate of water content with 75% shading. $R.$ $indicum$ showed higher photosynthetic capacity with higher level of shading, and its photosynthetic capacity reached the highest level ($9.63{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). On the other hand, shading-treated $R.$ $indicum$ showed higher intercellular $CO_2$ concentration, stomatal conductance and transpiration rate (55% shading > 35% shading > 75% shading) than non-treated ones. In addition, non-treated seedlings showed higher water use efficiency than treated ones. In particular, it was found that the leaf color of $R.$ $mucronulatum$ turned equivalent to purple under full sunlight, while its leaf color kept equivalent more to green with higher level of shading, as evidenced even in naked eyes. According to comprehensive analysis using Munsell Color Chart on potential leaf color variations of $R.$ $mucronulatum$ depending on the level of shading, it was found that relatively many leaf colors under full sunlight were equivalent to R (red) and Y (yellow) chart, while relatively many leaf colors with higher level of shading were equivalent to G (green) and Y chart, where the latter still showed green color.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.281-285
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• 2012

The aim of this research was carried out that leafty and tonic vegetable using garlic (Allium victorialis L. var. platyphyllum Makino) makes use of landscape ground-cover plant. Following shading level treatments (30%, 50%, 80%), garlic was cultivated to investigate plant growth characteristic and chlorophyll content. Leaf number of all treatments was unaffected, and 80% shading treatment had grown vigorous growth 16.8 cm leaf length and 10.1 cm leaf width compared to 13.4 cm leaf length and 7.3 cm leaf width for the non-shading treatment. Fresh weight of non-shading treatment was better than those of three shading treatments, however, 80% shading treatment had produced 10.4 g fresh weight of stem part compared to 8.5 g for the for the non-shading treatment. The chlorophyll content of the 50 and 80 shading treatments showed 42.8% and 40.5% respectively. These treatments increased 36.7% chlorophyll content compared to non-shading treatments. Following shading level treatments, growth characteristics of garlic in 80 shading level treatment shows outstanding growth and it is worthy of planting as shading ground-cover plants.

• Korean Journal of Medicinal Crop Science
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• v.8 no.3
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• pp.209-215
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• 2000

This study was conducted to improve the productivety of Ligusticum chuanxiong HORT. and Cnidium officinale MAKINO by establishing the effects of cultivating conditions. Growth characteristics of underground part of L. chuanxiong under the different mulching treatment showed the highest growth and yield in black vinyl mulching treatment. The highest dry weight of underground parts per plant in mulching treatment was 47.9g at white shading treatment while the lowest one was 16.5g at black shading treatment. Growth characteristics of underground parts C. officinale under the different mulching treatment were the higher in black vinyl mulching rather than in rice straw mulching and white vinyl mulching. Dry weight of underground parts per plant of C. officinale under the different shading treatments was the highest(37.8g) under the white shading while it was lowest(12. 2g) under the black shading.

• The Journal of Natural Sciences
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• v.10 no.1
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• pp.63-71
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• 1998

This research was conducted to control flowering of azalea (Rhododendron spp.) by shading, chilling and gibberellin treatments. Higher shading among treatments resulted in extended duration of flowering (DF) and increased number of flowers (NF) in all varieties tested. Number of days to flower (NDF) was increased in 'Ripple' by shading treatment, but this was not affected in other was vice verse in 'Reinhold Ambrosia' resulting in decreased NDF. Chilling treatment followed by high shading increased NDF and shortened DF in 'Inga' and 'Ripple', but that extended NDF and DF and increased NF in 'Reinhold Ambrosia'. In flowering response to $GA_3$ resulted in decreased NDF and increased NF. These results indicated that treatments of shading, chilling and gibberellin to azalea extended DF and increased NF, but NDF appeared different according to varieties.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.2
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• pp.146-154
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• 2014

In the result of effect on freezing damage reduction by the shade net colors and the shade rate to tea trees during wintering period, the high shade ratio decreased tea trees growth and increased freezing damage and 55% of shade ratio based on non treatment developed new leafs and green leaf productivity. By the shade net colors, colorless shade net (55% of shade type) treatment and green shade net treatment increased green leaf productivity and decreased damaged area compare to non treatment shade net and black shade net treatment. Colorless net shade treatment reduced over 50% of freezing damage and increased (10a) 68 kg for green leaf productivity compare to non treatment shade net. The colors of shade net treatments for reduction freezing damaged in order of Black < Green < Colorless but reduction of freezing damage was so high. In the relative microclimates, treatment shade nets were $0.7^{\circ}C$ lower, average relatively humidity 14.9% higher, soil temperature $0.6^{\circ}C$ lower and soil moisture 4.6% higher than non treatment shade net. And treatment shade nets decreased average wind speed 0.7 m/s and it showed us treatment net shades effected to excessive evapotranspiration and soil dry by wind and considered one of good solution for freezing damages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.146-154
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• 2021

This study was conducted to determine the degree of reduction in the yield of sweetpotato subjected to different shading treatments according to the growing season of the typical viscous sweetpotato 'Hogammi' and the powdery sweetpotato 'Jinyulmi'. Shading was provided using commercially available shading nets (55% and 75% shading level), and the treatments were applied at the following stages of storage root growth: SFS: the storage root formation stage (planting-50^th day), SSS: the storage root swelling stage (50-90^th day), and SAS: the storage root actively swelling Stage (90-120^th day). The growth characteristics according to shading treatments during each growth period, the number of tubers obtained at harvest, and sugar contents were investigated. For both assessed cultivars, there was no significant difference between the control group and the 55% shading treated group with respect to the maximum quantum yield (Fv/Fm) of photosystem II under different shading treatments, whereas the 75% shading group showed slightly higher values than the control group. In both cultivars, the contents of chlorophyll a and b tended to increase in plants subjected to shading treatments compared with the control plants, particularly that of chlorophyll b. Compared with the control group, the chlorophyll b content of 'Hogammi' subjected to 55% and 75% shading increased by 47% and 41%, respectively, whereas that of 'Jinyulmi' increased by 39% and 34%, respectively. We also detected reductions in the dry weights of the above- and belowground parts of the two varieties in response to shading compared with the control, with the reduction in the dry weight of belowground parts being significant. Furthermore, in both varieties, the T/R rate tended to increase in response to shading treatment. Owing to the lack of sunlight, both cultivars tended to suppress the formation and enlargement of tuber roots. Consequently, post-harvest yield analysis revealed that under shading treatments, both cultivars were characterized by poor tuber root growth according to growing season, with the yield of 'Hogammi' showing a greater reduction compared with that of 'Jinyulmi'. In addition, we found that the higher shading level also significantly reduced yields. Compared with the storage root formation and storage root actively swelling stages, shading treatments during the storage root swelling stage significantly affected yield reduction in both varieties.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.82-82
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• 2018

산채는 주로 산지에서 자생하는 것을 채취하거나 자생지와 비슷한 환경의 임간에서 재배하여 수확을 한다. 본 시험은 차광처리를 통해 산지가 아닌 노지에서 산채 재배 가능성을 검토하고자 하였다. 대상작목은 개미취(Aster tataricus), 눈개승마(Aruncus dioicus var. kamtschaticus), 단풍취(Ainsliaea acerifolia), 박쥐나물(Parasenecio auricudatus var. matsumurana), 산마늘(Allium microdictyon), 어수리(Heracleum moellendorffii), 우산나물(Syneilesis palmata)이다. 시험작목을 전북 남원시 허브시험장(표고 500m) 포장에서 2017년 4월에 종묘를 정식하여 약 2년간 재배하였다. 고온기인 5월부터 9월까지 35%, 55%, 75%, 95% 차광정도를 달리하여 설치 한 후 시설 내의 기온, 상대습도 등 환경조건 및 재배작물의 고사율, 출현율, 생육특성 등을 조사하였다. 시설 내부의 평균 기온은 차광정도가 높아질수록 다소 낮아졌으며, 상대습도는 점차 높아졌다. 차광정도별 고사율을 조사한 결과 개미취, 어수리, 우산나물의 경우는 차광비율에 상관없이 각각 3.6%, 5.7%, 9.8%로 낮게 나타났다. 반면 단풍취와 산마늘의 경우 차광 비율에 따른 편차가 크지는 않았지만 최대 고사율이 각각 20.0%, 36.8%로 다소 높게 나타났다. 또한 눈개승마 75% 차광에서 50.0%, 박쥐나물 35% 차광에서 100% 고사율을 보여 적정 차광비율 선정 필요하다고 판단된다. 정식 2년차 4월 평균 출현율은 개미취 100%, 눈개승마 86.2%, 단풍취 84.3%, 박쥐나물 77.9%, 산마늘 97.5%, 어수리 88.9%, 우산나물 96.3%이었다. 다만 단풍취, 박쥐나물은 차광정도가 높아질수록 출현율이 높아졌고, 어수리는 차광정도가 높아질수록 다소 출현율이 낮아졌다. 또한 생육특성 조사 결과 초장은 단풍취를 제외하고 차광처리별 경향성이 뚜렷하게 나타나지 않았으며, 엽장과 엽폭은 산마늘을 제외한 작목들은 차광이 강할수록 커지는 경향이었다. SPAD 값은 개미취와 산마늘은 처리구역별 차이가 없었으나, 나머지 작물은 차광이 높아질수록 SPAD 값도 커졌다. 시험결과 표고 500m지역에서 개미취, 산마늘, 어수리, 우산나물은 차광수준에 따른 생육의 차이가 크지 않거나 차광이 낮아도 생육이 비교적 양호하였다. 그러나 단풍취와 박쥐나물은 차광정도에 따라 생육의 차이가 분명하였으며, 차광이 높아질수록 생육이 좋아졌다. 이를 바탕으로 산채류 노지재배를 위해서는 연차 간 작목별 생육특성, 수량성, 상품율, 경제적 분석 등의 추가적인 조사가 이루어져 할 것으로 여겨진다.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.239-243
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• 2006

Orostachys japonicus, a monocarpic plant, is artificially grown in greenhouses. The study was carried out to examine the effect of shading (0, 35, 55, 75, 95%) on growth, morphological characters, and flowering. The treatments were done on August 25 and afterward samples were taken every 2 weeks until October 20, in which growth, morphological and flowering related characters were measured. With severer shading plant height, inflorescence length, number of leaves including bracts and stem diameter were decreased although severely declined in 95% shading treatment. Leaves and bracts, stem, root, shoot and total dry weights increasingly declined with severer shading. Florets formed on the inflorescence showed similar response to the shading treatment as plant height did. Flowering of the florets was not observed throughout all the sampling period, meaning that different light intensities by shading did not affect their flowering.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.547-555
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• 2014

This study was carried out in order to investigate the germination and the early growth characteristics of Parasenecio firmus. Seed pre-treatment before the each experiment was carried out by shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 48 hours). Experiment was performed by shading treatment (full sunlight, 35%, 50%, 75%, and 95% shading). Seeds of Parasenecio firmus were surveyed the highest germination rate (61.1%) in full sunlight with WS (overall 25.7~61.1%). Height was surveyed the highest under 95% shading. And root collar diameter was surveyed the highest in full sunlight. Fresh weights (leaf, shoot, root and total) were the highest under 50% shading. Dry weights (leaf, shoot and total) were the highest under 75% shading. It was indicated the lowest leaf, shoot, root and total under 95% shading. Leaf growth (leaf area, leaf length, leaf width and leaf thickness) and root growth (total root length, root project area, root surface area, root diameter and root volume) were good under 35%~75% shading, but the lowest under 95% shading. As a result of surveying the whole experiment, seed of Parasenecio firmus grows well under 50%~75% shading after germination by high sunlight with water soaking (WS).