• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.565-570
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• 2017

In a plumcot 'Harmony' cultivar, which is an interspecific hybrid between plum and apricot, canopy occupation and productivity according to tree training system, Y shape with no trellis (YNT) and Y-palmette with trellis (YPT), were compared. According to the survey results for 5 years of planting, tree growth was similar in two training systems. However, canopy occupation and fruit yield of YPT were significantly higher than those of YNT. The fruit weight and sugar content were not significantly different between two systems. The fruit drop rate tended to be lower in YPT than in YNT. From the above results, it is expected that the YPT type will contribute to the increase of canopy occupation and fruit yield and reducing the fruit drop rate compared to the YNT.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.515-523
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• 2012

Recent development and enlargement of reclaimed lands along the sea shores required to explore alternatives to existing crops, which are suitable to grow well and to declare higher profits. The objectives of this study were to investigate yield-related parameters for development of new leafy vegetables, and to screen some candidates among New Zealand spinach genotypes which were collected in Korea. Initially all the collected genotypes were grown for 7 weeks in a greenhouse of the experiment field in Chungnam National University, and then transplanted into the field to measure morphological or physiological parameters (plant height, branch number, stem diameter, chlorophyll content, and maximum canopy diameter), and yield-related parameters (leaf number, leaf length, leaf width, fresh weight and dry weight). Those parameters were quantitatively measured at 1, 5 or 9 weeks after transplanting (WAT). Parameters exhibiting statistically significant difference among the accessions were plant height, branch number, maximum canopy diameter, chlorophyll content, and leaf length. In contrast to highly correlated parameters with fresh and dry weight obtained in salt-affected soil in the earlier report, fresh weight was correlated significantly with leaf length (r=0.72), leaf width (r=0.64), and canopy diameter(r=0.66), while dry weight was correlated significantly with plant height (r=0.46), leaf length (r=0.72), leaf width (r=0.73), fresh weight (r=0.79), chlorophyll content (r=0.47), and canopy diameter (r=0.87). Based on the significantly correlated with yield parameters, the candidate accessions which were ranked in top statistical groups include CNU06A01, CNU06A13, CNU06A26, CNU06A35, CNU06A38, and CNU06A55. In order to be cultivated in reclaimed lands, it is necessary to screen out salt tolerant accessions among the above high-yielding genotypes.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.441-447
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• 2021

It were investigated changes in internal and external temperature, relative humidity using tyvek, weedstop, and 35% shading net as covering material to reduce the freezing damage of 'Shiranui' hybrid mandarin grown in open field. It were also evaluated canopy covering effect and LT₅₀ of leaves by covering material when it was cold at -2℃. In tyvek, temperature difference between inside and outside was low at the height of 1.5m and was high at 0.4m. The relative humidity differed greatly between day and night, and was high at 6-8 a.m. At -2℃, Sum of temperature at the height of 1.5m of canopy for 24-hour after covering were at 3.4℃ higher in tyvek than in control. The LT₅₀ of leaves was at 1.51℃ in tyvek, 1.33℃ in withstop, and 1.61℃ in 35% shading net lower than in control. Considering thermal insulation and relative humidity in canopy, tyvek is expected to reduce low temperature damage when covering after making a fine hole for ventilation.

• Journal of Crop Science and Biotechnology
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• v.10 no.3
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• pp.193-200
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• 2007

Mungbean plants generally have a relatively close canopy, thus a large amount of self-shading can reduce yield due to poor light penetration. Modification of leaflet type can affect leaf canopy and could alter seed yield. Two multiple leaflet mutants were obtained from gamma-ray irradiation and used to study the mode of inheritance related to leaflet types and to evaluate their agronomic features. The cross between large-heptafoliate leaflet with small-pentafoliate leaflet mutants produce all $F_1$ plants with normal trifoliate leaflets. The $F_2$ plants segregated in leaflet size and leaflet number into a 9:3:3:1 ratio of large-trifoliate: large-heptafoliate: small-pentafoliate: small-heptafoliate plants, suggesting that independent loci control leaflet size and leaflet number. Regarding leaflet number, the $F_2$ population can be classified into normal-trifoliate, small-pentafoliate, large-heptafoliate, and small-heptafoliate at the dihybrid ratio of 9:3:3:1. The gene symbols $N_1,n_1$ and $N_2,n_2$ are proposed to represent leaflet number. Since no plant was found with large-pentafoliate leaflets, we hypothesize that the $N_2$ allele expresses pleiotropic effect on both leaflet number and leaflet size. Another possibility is that an additional locus with S and s alleles controls leaflet size and S is tightly linked with $N_2$. The effect of multifoliate leaflet on yield and yield components was evaluated in four mungbean families each with four leaflet isolines under three environments. Averaging across the families and environments, the normal-trifoliate and large-heptafoliate lines gave higher yield than small pentafoliate and heptafoliate ones. These two large leaflet lines also had higher leaf area per plant than the other multifoliate lines. Therefore, the mungbean lines with a greater leaf area, which were likely to intercept more sunlight, gave greater yield. Three AFLP markers that were found to be linked to number of leaflets per leaf, corresponded to the N1 allele of the smallpentafoliate parent.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.47-54
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• 2007

This study was conducted to clarify the characteristics of habitat structure and bird communities between natural deciduous forest and around the road from October 2005 to August 2006 in the National Arboretum, Gwangneung, Korea. There were more larger trees and higher coverage of crown canopy in the natural deciduous forest than around the road. A total thirty seven species of birds were observed in the natural deciduous forest and twenty species were around road. The observed number of bird species and individuals, and bird species diversity index (H') were higher in the natural deciduous forest in each season. Foraging and nesting guild structures were also different. The differences of characteristics of bird communities would be related with habitat structure between both study areas.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.369-379
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• 2021

This study was a descriptive survey study to compare the stress, depression, fatigue, and sleep quality between pregnant women with gestational diabetes mellitus (GDM) and normal pregnant women. The study subjects were 49 gestational diabetes mellitus women and 51 normal pregnant women who were matching with gestational diabetes mellitus women by age, gestational age and number of births. The data collection was measured using structured questionnaires, numerical scales, and Canopy9 RSA(IEMBIO, Gangwondo, Korea) equipment. As a result of the study, pregnant women with gestational diabetes had higher pre-pregnancy weight(t=3.698, p<.001) and higher stress(t=4.505, p<.001), depression(t=4.564, p<.001), and fatigue(t=3.709, p<.001) during pregnancy, so weight management is important before pregnancy, and stress, fatigue, and depression relief nursing

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.342-356
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• 2014

This study aims to provide the fundamental data for restoration through the analysis of vegetation structure characteristic for managed area with deforest and fumigation among the places damaged by oak wilt disease in Bukhansan National Park. Study areas were selected in six damaged areas with 18 plots ($20m{\times}20m$) including comparing plots between year 2006 and year 2011 after preliminary study finding the exact location with easy access. Analysis items are density and coverage of under story layer, Importance Percentage of under story layer and Importance Percentage of urban adapted species and alien species. As a result, density and coverage under the canopy layer's vegetation was higher than comparing plot in Musugol valley and Soquicheon valley which 4 years and more passed. And Wondobong, Darakwon, Doseonsa and Dobong valley which had not been passed 3 years after deforestation and fumigation decreased in those of vegetation. However, the plots in Wondobong and Doseonsa was analyzed to be higher in density of shrubs than comparing plot. In terms of distirbution of species in under canopy layer which is grown as a upper vegetation, Quercus serrata and Sorbus alnifolia dominated each other in under canopy layer except for Wondobong and Darakwon. Wondobong continuously maintained Quercus mongolica and Q. mongolica and Pinus densiflora dominated in under canopy layer of Darakwon. S. alnifolia which is Urban adapted species were distributed in most study areas. In terms of alien species, Magnolia obovata and Robinia pseudoacacia were newly intruded in the opened crown, and Pueraria thunbergiana was distributed in Soquicheon valley. As the result of soil analysis, acidification(pH 4.49) and low level of organic matter(3.23%), available phosphate(1.40mg/kg) and exchangeable cation were analyzed and it was considered that those environment poorly support the vegetation growth.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.231-241
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• 1992

To study the relationships between major micrometeorological elements and their influences on evapotranspiration(ET) in the canopy of two rice cultivars, Daecheongbyo and Samgangbyo, synoptic meteorological factors, micrometeorological elements and ET from the canopy and biomass production were observed at various growth stages in the paddy field of Suwon Weather Forcast Office in 1989. ET from the rice community was highly correlated with the following factors in order of pan evaporation>air temperature>leaf temperature>solar radiation>sunshine duration>difference in vapor pressure depicit(VPD)>water temperature. ET observed showed higher correlation with the evaporation from small pan than that from Class A pan. Varietal difference would be noted in the relationships between ET in Samgangbyo canopy and the evaporations observed from the pans, with which closer a correlation was found in Samgangbyo than in Daecheongbyo. The ratio of canopy ET to the evaporation from Class A pan was maintained over 1.0 through the growth stages with the maximum of 1.9 at the late August. The evaporation observed from Class A pan was amounted to 71.9% of that from small pan. ET was better correlated with solar radiation than with net radiation which reached about 66% of solar radiation. Maximum temperature showed higher correlation with ET than mean air temperature, and also wind speed of 1m above ground revealed positive correlation. The relative humidity, however, had no correlation with the exception of ET in rainy days. A regression model developed to estimate ET as a function of meteorological elements being described with $R^2$ of 0.607 as : $ET=-5.3594+0.7005Pan\;A+0.1926T_{mean}+0.0878_{sol}+0.025RH$.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.241-241
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• 2017

Sweet potatoes (Ipomoea batatas (L.) LAMK.,) have been cultivated in Central and South America for about 2000 years and are now grown mainly in Asia and South America. Sweet potatoes are annual in the temperate region, but are classified as perennial in the tropical region. In 2000, the cultivation area of sweet potatoes decreased to about 16,000 ha in 2000, but the cultivation area increased slightly in recent 20,000 ha in Korea. Sweet potatoes do not show higher maximum dry matter production of 120 ~ 150g per plant, and the leaf area index (LAI), which maximizes dry matter production, is known as 3.0 ~ 4.0. As the leaf area increase, the penetration of light into the canopy becomes poor, and sufficient photosynthesis cannot be achieved in the lower leaves, on the other hand the respiration increase, which results in poor dry matter production. This study was conducted to know the responses of sweet potatoes to intensive shading treatment of 80% shading. This experiment was conducted for about 42 days from September 6, 2016 to October 18, 2016 at Gyeongsang National University Experimental Farm, Jinju, Korea. The plant canopy was shaded with black nylon 80% shade cloth suspended 1.2 m above the ground. The photosynthetic rate, stomatal conductance, chlorophyll fluorescence, SPAD and NDVI were measured in 3 replicates every 7 days after shading initiation. After the fresh weight was measured, the samples were dried at $80^{\circ}C$ in a dry oven and measured. By the 80% shading treatment, chlorophyll fluorescence of the treated plants was slightly higher than that of the control, the SPAD value was higher by 3.4 and NDVI value was higher by 0.01. However, photosynthetic rate and stomatal conductance were lower than those of the control. The stomatal conductance of the control were two times higher than those of the control and the photosynthetic rate of the control was four times higher than that of the control. In control, plant showed a tendency to steadily increase in fresh weight and dry weight. However, in the case of shading treatment, the tendency to increase in the fresh and dry weight of tuberous roots was not clear. The fresh weight of shoot showed a tendency to increase steadily while the difference between treatment and control was not large, but tended to decrease after frost.

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.20-27
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• 2020

The study was performed to calculate canopy temperatures and crop water stress index (CWSI) of 2-year-old 'Yumi' peach trees using thermal infrared imaging under different soil water conditions, and to evaluate availability for water stress determination. Canopy temperatures showed similar daily variations to air temperatures and they were higher during the daytime than air temperatures. Canopy temperatures for 24 h were correlated highly to air temperatures (r² =0.95), solar radiations (r² =0.74), and relative humidity (r² =-0.88). In addition, soil water potential showed a highly negative correlation to canopy temperatures (r² =-0.57), temperature differences between leaf and air (TD) (r² =-0.71), and CWSI (r² =-0.72) during the daytime (11 to 16 h). CWSI for 24 h was highly related to canopy temperatures (r² =0.90) and TD (r² =0.92), whereas CWSI was not correlated to soil water potential (r² =-0.27) for 24 h but related highly to water potential (r² =-0.72) during the daytime (11 to 16 h). Correlation coefficients between CWSI (y) and soil water potential (x) were highest from 11 to 12 h and a regression equation was deduced as y = -0.0087x + 0.14. CWSI was calculated as 0.575 at -50 kPa, which soil water stress generally occurs. Thus our result suggests that this regression equation using thermal infrared imaging is useful to evaluate soil water stress of peach trees.