• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.231-236
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• 2004

Crop productivity would be determined by relative capacity of source and sink. The study was carried out to measure the effects of shading and flower bud pinching on growth and yield of Atractylodes japonica Koidz. Shading treatment after transplanting was done at 100%, 65, 45 or 25% level of natural light intensity but the pinching treatment was to remove all the inflorescences formed after June 10, July 10, August 10 or none. Growth and yield at early and late stages were periodically measured. At the early stage, shading mainly influenced fresh weight rather than morphological characters. At the late stage, however, severer shading decreased numbers of stems, leaves, roots, fraction and total fresh weight. 65% shading from July 1 to September 30 after skipped the emerging and early growth stages showed nearly same growth and morphological characters but more rhizome yield per unit area than non-shading. In flower bud pinching treatment, earlier pinching increased number of roots, fraction fresh weights per plant and rhizome yield per unit area.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.598-608
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• 2011

The purpose of this study was to examine potential effects of shading and fertilizing treatment - two basic applicable factors in production of 1-year-old container seedling - on growth and seedling quality of Quercus myrsinaefolia, one of evergreen tree species in warm temperate zone of Korean. Every experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Based on fertilizing treatment, this study made an experiment in 4 groups of container seedling: control (non-treated seedlings) and 1000, 2000, 3000 ppm group (3 groups with different concentrations of water-soluble fertilizer (N:P:K=19:19:19, v/v). Seedlings under 55% shading with 2000 ppm concentration showed the highest height (totaling 21.1 cm), and under 35% shading with 2000 ppm concentration showed the highest root collar diameter growth (totaling 3.96 mm) among others. All three fertilizing groups except control showed H/D ratio ranging from 4.27 to 5.26 regardless of fertilizer concentration under 35% and 55% shading where container seedlings showed a tendency toward excellent growth of height and root collar diameter. Overall, 2000 ppm group under 55% shading showed highest dry mass production of leaves (1,292 g) among others, while 2000 ppm group under 35% shading showed highest dry mass production of shoots and roots (0.592 g and 0.998 g, respectively) among others. Also, it was found that 2000 ppm group under 35% shading showed the highest dry mass production of whole seedling, which was followed by 2000 ppm group under 55% shading and 3000 ppm group under 35% shading, respectively. According to analysis on LWR of Quercus myrsinaefolia depending on shading and fertilizing treatment, it was found that 3000 ppm group under 75% shading showed highest LWR level among others, whereas every fertilized group showed lower RWR level than control without fertilizing regardless of shading levels. In general, all fertilized groups under 55% shading had relatively high quality index (QI), and 2000 ppm group under 35% shading had highest QI among others. Based on the findings of this study, it is concluded that shading level ranging from 35 to 55% and fertilizing concentration of 2,000 ppm are suitable for producing 1-year-old container seedlings of Quercus myrsinaefolia with excellent growth and high quality index.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.496-504
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• 1996

The study was conducted to obtain the basic information on increasing aromatic degrees by shading and organic matter application on Condonopsis lanceolata. The result were as followings : Fresh root wt. in shading 55 % treatment was increased about twices, whereas fresh root weight in non-shading was decreased. But growth of ground parts such as vine length, leaf width, and leaf number was promoted under non-shading treatment. Macroelements such as K, Ca, and Mg, were increased in non-shading and higher organic matter application. The components such as crude protein, fiber, and ash were increased in the shading 55% treatment compared with non-shading. In the sixteen amino acids, arginine contents were the highest in non-shading and organic matter 30M/T. Recovery yield of essential oil was 0.005% in non-shading. The highest was organic matter 30M/T in the non-shading as 0.007%. Major aromatic constituents were 11 kinds of aliphatic alcohols such as I-hexanol, cis-3-hexenol, and trans-2-hexanal. As a result, major aromatic degree was higher in shading 55%, also increased in the much organic matter application. It was considered to be applied dense shading 55% and much organic matters to produce Condonopsis lanceolata plants which have high aroma and good quality.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.373-381
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• 2011

This study was carried out to investigate the growth and physiological responses to shading treatment of 1-year-old containerized seedling of Quercus myrsinaefolia. Experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Height and root collar diameter growth were high in the seedlings under both 35% and 55% shading. Regardless of shading level, root collar diameter growth lasted for more than 4 weeks compared to height growth. Highest H/D ratio was observed in the seedlings under 35% shading as 4.31, and the lowest ratio was 3.63 under 75% shading. It was found that seedlings under 55% shading showed highest dry mass production, which was followed in seedlings under 35% shading. In case of leaf dry weight ratio (LWR) after shading treatment, the highest value was 0.53 under 55% shading, and followed in seedlings under 35% shading as 0.52. But root dry weight ratio (RWR) was highest as 0.36 under 75% shading (highest level of shading). In terms of shading treatment, it was found that the higher level of shading had a tendency toward the higher content of chlorophyll a and the higher total chlorophyll content in the leaves of Quercus myrsinaefolia, but there was no significant difference in the content of chlorophyll b depending on the level of shading. It was found that high photosynthesis and transpiration rate were more correlated with high level of shading than full sunlight, but the rates of seedlings had a tendency to be higher under 35% and 55% shading than under 75% shading. The results on growth and physiological responses to different shading levels of 1-year-old containerized seedlings of Quercus myrsinaefolia could be useful in setting up the optimum light intensity for growth, and in estimating the shade tolerance of the species.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.320-327
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• 2016

Allium hookeri is used for food and medical materials in Asia. This study was carried out to elucidate the effects of shading rates on growth and quality of A. hookeri cultivation in greenhouse. Treatments were given with 35%, 55%, 75% and 95% shading rates and non-shading (Control). Photosynthesis photon flux density (PPFD) of control, 35%, 55%, 75%, and 95% shading were 792, 515, 351, 182, and $78.2{\mu}mol{\cdot}m{\cdot}s^{-1}$ respectively. The emergence ratio was 98% under non-shading, 35% and 75% shading condition, and it was 100% under 55% and 95% shading condition on April 20, 2016. These results showed no correlation between emergence rate and shading treatment. When shading net was set up inside at greenhouse, fresh weights in control, 35%, 55%, 75%, and 95% shading treatments were 1,142, 3,511, 5,936, 6,408 and 3,779kg/10a, respectively. When shading net was set up outside at greenhouse, fresh weights in control, 55%, 75%, and 95% shading treatments were 1,372, 5,442, 6,238 and 3,595kg/10a, respectively. Dry weight, percentage of dry matter, number of leavesand branches, plant height and root length in 75% shading treatment were higher than other shading treatments. From these results, we suggested that the proper shading rate in a greenhouse is 75% for A. hookeri cultivation in middle area of Korea.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.68-74
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• 2013

This study was conducted to analyse the effectiveness of shading on growth and arsenic absorption of Pteris multifida, known as hyperaccumulator of arsenic, from paddy soils contaminated with heavy metals. Study was carried out in paddy soil polluted by arsenic near the former Janghang smelter. P. multifuda in the same growth stage was planted with $20{\times}20cm$ intervals in each experimental plot ($2{\times}2m$), and cultivated for 24 weeks. The growth of P. multifuda according to shading conditions was evaluated, the accumulated amount of arsenic in plants and arsenic variation in the soil was analyzed using ICP. In the result of this study, the growth of P. multifida cultivated under shading treatment was vigorous than non-shading. Accumulated amount of arsenic in aerial parts of P. multifida cultivated under non-shading ($169.8mg{\cdot}kg^{-1}$) was slightly higher than shading ($140.9mg{\cdot}kg^{-1}$), and those in underground part were almost the same. But the growth was great in 70% shading treatment. Therefore, arsenic contents absorbed from soils was much higher in shading treatment. Arsenic translocation rate (TR) of P. multifida was very high (0.87~0.89) regardless of shading conditions. So arsenic in soil could be efficiently eliminated by removal of aerial parts.

• Journal of Environmental Science International
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• v.31 no.5
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• pp.405-411
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• 2022

Production of lettuce under indoor cultivation is highly affected by light intensity. In this study, we used shade cloth (commercial black net) to examine the effect of these condition on growth without an associated yield penalty of container-grown lettuce. Four levels of shading treatments (0%, 35%, 55%, and 75% referred to as Cont., S₃₅, S₅₅, and S₇₅ with respect to Cont.) and two lettuce varieties (red and blue) were evaluated. Variety-specific growth responses were observed with respect to different levels of shading treatments. High growth of red lettuce was occurred in Cont. treatment despite plant height and leaf length being higher than Cont. However, under 35% shading treatment blue lettuce was higher than in control plants. The highest root length was observed 0% shading (Cont.) of both varieties. These results reinforce the idea that blue lettuce is the better leafy vegetable rather than red lettuce for indoor cultivation related to lower light intensity environment conditions.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.227-232
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• 2015

This experiment was carried out to investigate the effects of shading materials (aluminum specific-shading screen and polypropylene non-woven fabric) and shading ratio (50% and 70%) on climatic changes, cut-flower quality, and yield of spray rose cultivars for export during high temperature periods. The daily cumulative solar radiations were higher with the aluminum specific-shading screen, especially with 50% shading compared to polypropylene non-woven fabric. Air temperature and root zone temperature within rockwool media greatly decreased with the aluminum specific-shading screen, but relative air humidity was not different among shading methods. Chlorophyll contents (SPAD values) were slightly higher with aluminum-specific shading screen than with polypropylene non-woven fabric, and were higher with 50% than with 70% aluminum specific-shading screen. Except for 'Lovely Lydia', marketable and exportable yields of all cultivars were higher with 50% than with 70% aluminum shading treatment. In addition, flowers talk length, stem diameter, number of node and 7ea-leaflet, and floret number tended to be better with aluminum specific-shading screen. Flower stalk length was higher with 70% than with 50% aluminum shading treatment. Chromaticity of petals slightly increased, and vase life was 0.5-2.5 days longer for each cultivar with aluminum specific-shading screen than with polypropylene non-woven fabric.

• 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 Bio-Environment Control
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• v.2 no.2
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• pp.136-146
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• 1993

In order to study flowering of Chrysanthemum coronarium, several investigations on the daylength, shading, irrigation and plant growth regulator treatment were carried out. As daylength was treated for 12, 14 and 16hrs, flowering was accelerated and plant height was increased. Leaf number, length and width were decreased by the increased daylength. Sensitivity to daylength and flower development were accompanied by the plant growth, especially the effect of long day treatment was appeared remarkably when the number of leaves was more than 8 leaves. The minimum days of long day treatment for flowering was more than 10 days. Flowering was delayed by 65% shading treatment, over irrigation.