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

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.69 no.3
• /
• pp.145-153
• /
• 2024

Crop damage is becoming increasingly prevalent because of the impact of climate change-induced abnormal weather conditions. This is particularly evident in the delayed rooting of transplanted rice, caused by insufficient solar radiation. This delay in rooting negatively affects crop growth, resulting in reduced yield and delayed development. To investigate the effects of shading and elevated temperatures during rooting stage on the early growth of transplanted rice seedlings, seedlings that had been cultivated for 15 days were transplanted into a greenhouse and subjected to varying levels of shading, including 0%(control), 34%, 44%, and 70%. The height of transplanted seedlings increased under 34% shading but decreased under 44% or more shading compared to that of the no shading treatment. As the degree of shading increased, the stem diameter and root length of the seedlings decreased significantly inhibiting growth, dry matter weight, and seedling quality. Additionally, shading increases the nitrogen content of plants because of the absence of soluble carbohydrates, thereby weakening them. The adverse effects of shading on plant growth was further exacerbated by high temperatures. These findings suggest that inadequate, sunlight and elevated temperatures during rooting stage, subsequent to transplanting, may result in delay plant development and decreased resistance of the seedlings to pests and environmental challenges. Therefore, it is essential to develop innovative cultivation management techniques during the rooting stage to improve growth outcomes.

• Journal of Bio-Environment Control
• /
• v.21 no.4
• /
• pp.419-427
• /
• 2012

This study was carried out to investigate the effect of two shading methods, shading agent spray on the glasshouse and internal shading screen treatment, on the growth and fruit quality of paprika (Capsicum annuum L. 'Cupra' and 'Coletti') in summer season cultivation. In the shading agent treatment, a commercial shading agent diluted with water at a ratio of 1 : 4 was sprayed on the roof of a glasshouse. In the internal shading screen treatment, a 10~20% shaded screen was used during the day time when the sun radiation was greater than $700W{\cdot}m^{-2}$. Compared to the unshaded control, photosynthetic photon flux density (PPFD) decreased in the greenhouse in the shading agent (SA) and shading screen (SS) treatments by 20% and 30%, respectively. Lower air temperatures and higher relative humidities were observed in the SA than in both the control and the SS treatment. Time to reach the break point of humidity deficit $8g{\cdot}m^{-3}$ was 2 hours late in the SA than in both the control and the SS treatment. Compared to control, both the SA and the SS treatments showed lower instantaneous temperatures of leaf, fruit, and flower by $2^{\circ}C$, $5^{\circ}C$ and $3^{\circ}C$, respectively. There were no differences in number of branches, stem diameter, and leaf size among treatments although both shading treatments promoted plant height in both cultivars. Botrytis infection ratio declined with the SA treatment by 14.7% in 'Cupra' and 22.1% in 'Coletti' as compared to that in the control. Shading increased fruit size in both cultivars, whereas no differences were observed in the number of locules and thickness of fruit tissue among treatments. Shading treatment increased mean fruit weight by a range of 10 to 15 g per fruit, while it decreased soluble solids contents as compared to that in the control. Similar Hunter values were observed among treatments, while fruit firmness increased slightly in shading treatments. Compared to the control, shading treatments improved marketable fruits by 11.7~22.6% and increased the number of fruits per plant by 4~9.2 in both 'Cupra' and 'Coletti'. The results of this study indicate that shading agent application on the roof of glasshouse would be one of the most effective options to reduce heat stress imposed on the paprika crop in summer cultivation, resulting in improved crop growth and fruit yield.

• Journal of Korean Society of Forest Science
• /
• v.102 no.1
• /
• pp.66-73
• /
• 2013

This study was conducted to determine the effects of rice hull cover on seed germination and tray types, soil types, shading conditions for seedling growth of Codonopsis pilosuala. We also examined the feasibility of cultivation of small seedlings transplanted in the Gyeonggi-do area for a month. Under control condition, the seed germination was 8% whereas it dramatically increased to 78% under rice hull cover treatment. Under the different conditions (tray types, soil types, and shading conditions), young seedlings showed the best quality without shading in TKS soil of 50 plug cell tray, with the growth characteristics of plant height (11.9 cm), number of leaves (71), leaf width (3.1 cm), leaf length (2.6 cm), and root length (14.3 cm). Seedling quality was the best without any shading in TKS+perlite, with the physiological characteristics of evaporation (3.9 $mmol{\cdot}m^{-2}s^{-1}$), carbon assimilation (9.1 ${\mu}mol{\cdot}m^{-2}s^{-1}$), and water use efficiency (2.2 ${\mu}mol{\cdot}m^{-2}s^{-1}$). Considering the economical, morphological, physiological and survival rate of the seedlings, it was an ideal method for transplanting seedlings in the field after they have been grown for 30-45 days in TKS and TKS+perlite of 200 plug cell tray in 0% or 30% shaded conditions. As the results of 5 months examination on the possibility to cultivate Codonopsis pilosuala in the Gyeonggi-do area, 88% to 96% of survival rate was observed with normal induced flowers. Therefore, cultivation of Codonopsis pilosuala was possible in the Gyeonggi-do area. While there were symptoms of etiolation and wilting under no shading condition, they did not appear in 30% and 70% shading conditions. Therefore, cultivation of Codonopsis pilosuala is considered to be necessary 30% or 70% shading.

• 월간낙농육우
• /
• v.36 no.9
• /
• pp.145-148
• /
• 2016

올 여름은 한 달이 넘도록 열대야가 지속될 정도로 가히 '살인적' 더위였다. 폭염으로 인한 고온 스트레스는 젖소들에게 단순히 산유량 저하뿐만 아니라, 다가오는 가을철에 수태율을 감소시키고 대사성 질병 면역력을 떨어뜨려 큰 피해를 준다. 이에 농가들은 고온 스트레스를 최소화하기 위해 차광막을 설치하거나 지붕에 스프링클러를 분사하는 등 하루하루 긴장 속에 이 계절을 보내야 했다. 하지만 올해 같은 폭염 속에서도 차광막 하나 없이 축사를 관리한 농가들이 있었다. 바로 'P.C(폴리카보네이트, Poly-Carbonate) 다기능 지붕재 엠보(이하 P.C엠보)'를 설치한 목장들이다. 직사광선의 피해를 최소화할 수 있는 'P.C 다기능 지붕재 엠보'를 개발한 (주)대한철강(대표 김상국)을 찾아가 봤다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1999.11a
• /
• pp.241-244
• /
• 1999

시설원예는 노지원예와 달리 인위적인 환경조절을 통하여 주년안정생산이 가능하여야 하고 단위면적당 생산성을 증대시키면서 품질향상을 극대화시키는 것이 생산의 목표이다. 따라서, 주년안정생산을 위하여 고온기에 작물생산이 가능하도록 시설내 고온환경을 조절해야할 것이다. 고온환경을 조절하기 위한 냉방방식에는 자연환기 및 팬을 이용한 온실내부의 공기를 치환하는 방법, 온실내ㆍ외부에 차광망을 설치하여 온실내로 유입되는 일사량의 일부를 차단하는 방법, 수분증발을 통하여 온실내부의 잠열을 빼앗는 증발냉각방식, 히트펌프나 에어컨을 이용한 기계적인 방법이 이용되고 있다. (중략)

• Journal of Practical Agriculture & Fisheries Research
• /
• v.16 no.1
• /
• pp.67-75
• /
• 2014

Use of mobile shading helps ameliorate heat stress of cucumber in greenhouse during summer. The mobile shading according to solar radiation may be optimal to produce high-quality cucumber in greenhouse during summer. Simultaneous comparison was made among greenhouse sections that were either not shaded or covered with reflective aluminized shadecloth that shaded 40%, or 90% of direct sunlight. Solar radiation amount, soil temperature, difference in leaf temperature and air temperature, and air temperature were lower, and relative humidity was higher as shade level increased. With increased shade level, photosynthesis rate, leaf area, fresh weight, dry weight, and number of marketable fruits increased. The mobile shading of 90% when the outer sunlight was above 650W·m^-2 yielded favorable growth environment in greenhouse of cucumber during summer.

• FLOWER RESEARCH JOURNAL
• /
• v.17 no.3
• /
• pp.185-189
• /
• 2009

This study was carried out to investigate the effect of shading (50% or not) and pruning height (3cm, 6cm, and 9cm) of remained above-ground plant part on shoot emergence aspect, mortality rate, flowering and cut flower characteristics of two years old Gypsophila paniculata plants. Days to shoot emergence (80%) advanced, emerged shoot number increased and mortality rate surveyed on late October decreased in 50% shading treatment. In addition to, mortality rate decreased, as above-ground plant part was highly pruned. Blooming was earlier with highly pruning the remained above-ground pan and under non-shading condition than shading. Growth traits such flower stalk length, primary branches number, stem diameter, and cut flower yield were the best and also non-particulate rate and rosette formation rate were the lowest in pruning height of 9cm under non-shading condition.

• 대한생식의학회:학술대회논문집
• /
• 1995.12a
• /
• pp.64.2-65
• /
• 1995

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