• Journal of Environmental Science International
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• v.29 no.2
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• pp.167-175
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• 2020

The purpose of this study was to investigate the effect of shading on the growth and productivity of strawberries. Photosynthesis was normally achieved under natural light without shading treatment, and vegetative growth of under- and aboveground part of strawberry plants were excellent. Strawberry fruit productivity and quality were different depending on shading conditions. In natural light, they were improved possibly by balanced vegetative and reproductive growth. However, under light-shading conditions with insufficient sunshine, photosynthetic activity deteriorated and carbohydrate production was therfore inadequate; this adversely affected plant height and quality. The negative effects were more pronounced at 50% shading condition. Shading treatments resulting in insufficient sunshine had a detrimental impact on plant productivity and growth; this implies that proper shading conditions could heip improve yield and fruit quality.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.342-348
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• 2014

This study was carried out to determine the effects of temperature and shading on germination and early growth of Pimpinella brachycarpa. Experiment was performed by temperature controls ($5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$, and $30^{\circ}C$) and shading treatments (control, 35% shading, 50% shading, and 75% shading). Seed pre-treatment before the germination experiment was carried out by temperature (with low temperature and wetting treatments for 0day, 20days, and 40days). Seeds of P. brachycarpa were, 20days of seed pre-treatment, germinated well at $5^{\circ}C$ and the more temperature went up, the more germination rate went down. As a result of surveying shading treatments, the height, leaf area, leaf length, leaf width etc were the highest (7.3cm, $12.8cm^2$, 5.4cm, and 2.3cm, respectively) under 50% shading. Specially, the root was grown well under 35% and 50% shading. Fresh weight of shoot (leaves+stem) was the highest under 50% and 75% shading and dry weight of shoot (leaves+stem) was the highest under 35% and 50% shading. As a result of surveying the whole experiment, it is concluded that the production of P. brachycarpa seedling is more effective under 50% shading.

• 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.

• 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 Medicinal Crop Science
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• v.21 no.5
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• pp.394-400
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• 2013

This study was carried out in order to examine the germination characteristics of Atractylodes japonica seeds, and it was to develop the more efficient pre-treatment and production system of the seeds. Experiment was performed by two ways-temperature control (10, 15, 20, $25^{\circ}C$) and shading treatment (full sunlight, 35, 50, 75, 95% of full sunlight). Seed pre-treatment before the each experiment was carried out by temperature (with low temperature and wetting treatment (LTW) for 0, 15, 30, 45 and 60 days) and shading treatment (with drying at room temperature (DRT), drying at low temperature (DLT) and water soaking (WS) for 48 hours). Seeds of A. japonica were germinated well under temperature control (overall 85.3~100%), especially high temperature. And, the seeds pre-treated with LTW for 45 days germinated with a 100% success rate. Under the surveying shading treatment, the highest germination rate was 95.8% with DRT and overall 63.2~95.8%. Germination rate under seeds with WS was 63.2~7.8%. As a result of surveying the whole experiment, A. japonica seeds don't need to pre-treat cause of high germination, but if it is performed with LTW for a certain period of time, it would be more productive.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.1-7
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• 2001

This experiment was carried out to investigate the effects of shading treatments and harvesting methods on the growth of Eleutherococcus senticosus, which was known as the medicine of anticancer, anti-stress, hepatic detoxification activity, immunoactivity, and tonic. Light transmission ratio and air temperature were decreased as $40{\sim}64%$,$1.9{\sim}2^{\circ}C$, respectively, in 30% to 70% shading net treatment compared to non-shading. Fifty percentage shading net treatment was effective for the growth and yield of Eleutherococcus senticosus. During summer Eleutherococcus senticosus was growing under shading net treatment compared to non-shading. Tunnel type was more effective for growth than vertical type in shading method. 30cm length included 2 to 3 nodes cutting from soil surface was the most effective for branching stem length, plant height and yield as harvesting methods.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.3
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• pp.163-168
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• 2021

The growth experiment under shading condition has been performed to understand the eco-physiological responses of crops to light in terms of photosynthesis. There are two types of shading: overall shading and partial shading. In this study, the chlorophyll fluorescence of soybean was observed under the overall shading of the box made by polyresin and the partial shading at agrivoltaic system. The overall shading condition during vegetative growth induced lower SPAD and Electron transport rate (ETR). These lower values recovered after removal of shading box. However, the Non-photochemical fluorescence quenching (NPQ) became lower under overall shading and higher under partial shading. Such increase in NPQ limited crop photosynthesis even though the ETR was almost same to the control without shading treatment. Under the condition of partial shading, the values of SP AD and ETR for soybean did not change. However, the NPQ was higher than control condition. This suggests that the crop photosynthesis under both types of shading would be decreased by different eco-physiological processes which are the lower ETR in overall shading and the higher NP Q in partial shading despite the reduced light under shading conditions.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.584-589
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• 2014

Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

• Journal of Bio-Environment Control
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• v.32 no.2
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• pp.157-164
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• 2023

Codonopsis lanceolata (S. et Z.) Trautv. is mainly cultivated in Korea and China as a medicinal crop. C. lanceolata is difficult to produce plug seedlings in the summer, because C. lanceolata has a low germination rate and is vulnerable to high temperatures. Cold treatment is effective in breaking dormancy of seeds and increasing the germination rate. Shading cultivation can control the solar irradiance received by plants and reduce the damage by high temperatures and strong light. This study was conducted to examine the appropriate cold treatment period for the improving germination of C. lanceolata, and shading level during the summer seedling period. Cold treatment experiments were conducted for 0 (control), 1, 2, 3, and 4 weeks at 4℃ before sowing. In the shading experiment, C. lanceolata was grown for 45 days with 0 (non-treatment), 45, 75% shading levels. Cold treatment for one week significantly improved the germination energy. The plant height, leaf area, and fresh and dry weights of C. lanceolata seedlings were significantly increased under the 45% shading level. Total root length, root surface area, and the number of root tips were significantly higher in shading treatment (45 and 75%) than in non-treatment. The C. lanceolata seedling's compactness and Dickson's quality index were the highest at 45% shading level. Therefore, these results recommended sowing C. lanceolata after cold treatment for one week at 4℃, and 45% shading level could stably culture C. lanceolata plug seedlings during the high temperature period.

• Animal Bioscience
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• v.34 no.11
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• pp.1766-1775
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• 2021

Objective: The oxidative stress status and changes of chicken ovary tissue after shading were studied, to determine the mechanism of the effect of shading on follicular development. Methods: Twenty healthy laying hens (40 weeks old) with uniform body weight and the same laying rate were randomly divided into two groups (the shading group and normal light group). In the shading group, the cage was covered to reduce the light intensity inside the cage to 0 without affecting ventilation or food intake. The normal lighting group received no additional treatment. After 7 days of shading, oxidative stress related indicators and gene expression were detected. Results: Analysis of paraffin and ultrathin sections showed that apoptosis of ovarian granulosa cells (GCs) increased significantly after light shading. Enzyme linked immunosorbent assay results revealed that the levels of total antioxidant capacity, malondialdehyde, superoxide dismutase (SOD), glutathione, catalase (CAT), and other substances in the sera, livers, ovaries, and follicular GCs of laying hens increased significantly after shading for 7 days; and reactive oxygen species (ROS) levels in the livers of laying hens also increased significantly. ROS in the serum, ovarian and GCs also increased. After shading for 7 days, the levels of 8-hydroxy-2 deoxyguanosine in the sera and ovarian tissues of laying hens increased significantly. Cell counting kit-8 detection showed that the proliferation activity of GCs in layer follicles decreased after shading for 7 days; the expression level of the anti-apoptotic gene B-cell lymphoma-2 in ovarian tissue and follicular GCs was significantly reduced, and the expression levels of pro-apoptotic caspase 3 (casp3), and SOD, glutathione peroxidase 2 (GPX2), and CAT were all significantly increased. Conclusion: Oxidative stress induced by shading light has a serious inhibitory effect on follicular development during reproduction in laying hens.