• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.166-170
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• 2000

This study was conducted in to elucidate the changes of growth characteristics and photosynthesis in three soybean (Glycine max L. cv. Danwonkong, Hwangkeumkong and Kwangankong) 30 day old seedlings to 100mM NaCl concentration containing 1/2 Hoagland's nutrient solution in sand culture. The main stem height and number of main stem node were decreased. thus, leaf area and dry matter were decreased with 100mM NaCl. Growth reduction was less little in Hwangkeumkong than other cultivars. The stem growth rate was affected less than other parts as root or leaf, by NaCl treatment. The specific leaf area (SLA), shoot : root ratio and leaf : root ratio decreased with NaCl solution except for those of Hwangkeumkong. There is no general tendency in leaf thickness by leaf position of three cultivars. The chlorophyll content (SPAD) of the primary and 2nd leaf slightly decreased under NaCl solution but rapidly increased in non-NaCl solution at 15 days after treatments. The photosynthesis, stomatal conductance and transpiration of 2nd leaf positions reduced by NaCl and there were a sigificant correlation between photosynthesis and stomatal conductance or transpiration.

• Korean Journal of Environment and Ecology
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• v.24 no.1
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• pp.62-68
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• 2010

This study was conducted to find out how the germination, phenology and leaf morphology of Phytolacca insularis(endemic species of Korea) and P. americana(alien species) react to the global warming situation. Seed and seedlings of two species were sampled and placed under two separate conditions for the experiment. One of the seed and seedlings was treated in the glass house with control(ambient $CO_2$+ambient temperature, (AC-AT), and the other with control(elevated $CO_2$+ elevated temperature, EC-ET), over the period of one year, 2008-2009. The germination rate of two species was fast, and the time of their germination started early, when they were treated at EC-ET than at AC-AT. Furthermore, the germination rate of Phytolacca insularis(endemic species of Korea) was found to be comparatively lower than that of P. americana(alien species). The former showed only vegetative growth whereas the latter showed both vegetative growth and reproductive growth in one year period. The more $CO_2$ degree and temperature increased, phenological responses of two species, including leaf growth, the formation of flower stems, flowering, and fruit maturing, became much faster, and the time of their leaf-yellowing was delayed. The lamina length of P. insularis was not significantly affected by elevated $CO_2$ and temperature. The lamina length of P. americana, on the other hand, became longer at EC-ET than at AC-AT, but the leaf width of both species increased at EC-ET. As for the number of leaves, both species showed no difference. Finally, the ratio of the leaf area of P. insularis was high at AC-AT, but P. americana was high at EC-ET. These results indicate that P. americana, aliens species, reacts more sensitively to global warming than P. insularis, endemic species, does.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.49-58
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• 1994

To investigate the relationship between leaf growth of several woody plants and ait tempera ture in early growing season (from April to June) in deciduous forests, I surveyed the changes of leaf area (LA), leaf weight (LW) and specific leaf area (SLA) of 19 specles, in two areas Namhansansung (NA) and Taegwallyong (TA) area in which that the latitudes are similer ($37^{\circ}28'N$ at NA and $37^{\circ}27'N$ an TA), but annual mean-temperatures were different ($11.8^{\circ}C\;in\;NA, \;6.3^{\circ}C$ in TA) for two years, 1991 and 1992. In the same species, the plants of NA began to grow 10-25 days earlier than those of TA, but the latter grew faster than the former. On 10 June the values of LA and LW per leaf were similar in the two areas but the maximum values of SLA were higher in NA. In the same plant, the values of LA and LW were constant year by year, except for PYIOLUS leveilleana, Quercus mongolica, Symplocos chznensis for. pilosa and S t y a r ubussiu. In N A , the leaves be gan to grow during the first ten days of April, and eariler in 1992 than in 1991, and daily mean temperature (DMT) of the former from 27 March to 6 April were higher than those of thc latter. But the LA increased faster in 1991 than in 1992. and DMT from 10 April to 16 April were higher in 1991 than in 1992.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.223-229
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• 2000

To develop the restoration technique from urban planted forest to natural forest, sprout growth and its effects on vegetation composition in the early stage after lumbering, were studied, using only Populus albaglandulosa of the tree layer in Chungdam Park Chungdam-dong, Kangnam-gu, Seoul during the two years from 1997 to 1998. The results were as follow. After lumbering, the more basal areas of the parent stump, the more sprouts were generated. The basal area of parent stump was related more to biomass than to the number of sprouts. In the cutting area, biomasses of sprouts were 552.7 g?DW/㎡ in first year and 8.7 g?DW/㎡ in second year after lumbering. Therefore, cutting of sprouts in first year resulted in decrease of sprout production in second year. In the non-cutting area, biomass of sprouts was 657.4 g?DW/㎡ and more than that of the experiment. Especially, 2-year sprouts grew to a 304 cm height by the end of the growing season in the second year. The growing season of sprouts was from early April to early September and almost all the leaves of the sprouts remained at the end of the growing season. Specific leaf area decreased along with time elapse and plant height but the differences were not conspicuous. Therefore, it is thought that the reason why p. albaglandulosa sprouts grew fast was due to a long growing period and lower layer leaves which remained at the end of the growing season. In the cutting area of the P. albaglandulosa sprouts, there were no changes in the number of species in the shrub layer but an conspicuous increase in the herb layer. Coverage was no changes in the shrub layer but an increase in the herb layer. In the non-cutting area of P albaglandulosa sprouts, the number of species and the coverage changed a little, and the main species of the herb layer were Phytolacca americana, Eupatorium rugosum and Panicum dichotomiflorum, which are tall plant species.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.9-15
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• 1972

Comparative analyses of canopy structure were conducted using newly bred high yield rice cultivars (IR 667-Suwon 213 and 214) and commercial varieties (Jinhung and Paldal) under the field condition. "Canopy score" as criteria of canopy structure was proposed. The results were summerized as follows: 1. IR667 line (IR8${\times}$Taichung Native 1${\times}$Yukara) showed lower canopy height, greater tiller openness, smaller leaf openness and leaf length ratio (flag leaf/3rd), shorter 4th and 5th internode length, greater diameter of 5th internode, consequently greater leaf area index, panicle weight and leaf weight ratio (leaf/leaf sheathculm) as merits, and greater leaf width, smaller leaf number(number of leaf/$m^2$)and specific leaf area($cm^2/g$) and faster destruction of canopy by senescence as demerits comparing with commercial varieties. 2. IR 667 line showed much higher "Canopy score", subsequently higher yield. 3. The quality of individual leaf was better in the commercial varieties indicating that the best combination for the better yield would be the leaf of commercial varieties with the structure of IR667 line.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.151-155
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• 1983

Photosynthetic activity of two rice varieties "Suweon 318, Nagdongbyeo" and two species of grass weeds, two species of sedge weeds, and four species of broadleaf weeds was measured at 5, 10, 20, 30, 40, 50 Klux light intensity. Relative photosynthetic activity of weed species was high in the decreasing order in Cyperus serotinus, Echinochloa grusgalli var caudata, Bidens tripartita, Monochoria vaginalis, and Ludwigia prostrata, while respiration rate was high in Bidens tripartite, Monochoria vaginalis and Cyperus serotinus. Light saturation point of Monochoria vaginalis and Sagittaria pygrnaea may be considered as at 30 klux and photosynthetic rate of other weed species increased with increasing light intensity. Photosynthetic activity of weed species was generally two times higher than rice at the light intensity of 50 klux and increased more than rice as light intensity increased. Photosynthetic activity per leaf dry weight and specific leaf area was higher in broadleaf weeds than in grass and sedge weed species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.94-98
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• 1982

To understand the growth pattern of ginseng plant under shading, the vertical distribution of leaf area, leaf area index (LAI) and specific leaf weight (SLW) and changes in light intensity as affected by planting position were investigated in 3 to 5 years old ginseng plant populations. Light intensity was vertically lowest at about 10cm above the ground and became low at the rear planting position in 3-year-old population. When culturing bed (96cm in width) were divided into three parts at intervals of 32cm from front to rear, the leaf area in 3-year-old population was largest in middle 1/3 part of planting bed. Light intensity affected the SLW positively, but LAI showed no distinct difference among planting positions. The light environment of 4-year-old population was worse than that of 3-year-old population and leaf area and LAI differed greatly among planting positions. In 5-year-old population, leaf dry weight and leaf area of furrow part (that is, the amount of leaves protruded from the plants which were planted in 1st, 2nd or 3rd lines into the furrow) increased. The dry weights of leaves and stem increased considerably as plant became aged, and were distributed mainly in upper layer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.463-467
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• 2004

This study was carried out to estimate of leaf area index (LAI) rapidly using plant canopy analyzer, comparing with specific leaf area (SLA) and leaf area ratio (LAR) in rice from 2001 to 2002 at Honam Agricultural Research Institute in Iksan Korea. The relationship between LAI values taken by plant canopy analyzer and by leaf area meter showed high correlation at each growth stages of rice. LAIs obtained by plant canopy analyzer were highly correlated with that by leaf area meter which were the highest in Dongjinbyeo and the lowest in Hapcheon1. Specific leaf area (SLA) of all rice cultivars were tend to decrease remarkably with the progress of growth stage. It was found that the SLA of Dasanbyeo was the highest and that of Hapcheon1 was the lowest among rice cultivars tested. Leaf area ratios (LARs) was also decreased with the progress of growth stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.386-391
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• 1987

Effect of growth light intensity (5% and 20%) and planting density (40, 56, 90/33㎡) on yield and red ginseng quality was investigated in a sandy loam field of ginseng plantation. High growth light intensity had no effect on yield and quality but decreased stem length, leaf area and chlorophyll content and increased specific leaf weight. The optimum planting density was 64/3.3㎡ for both yield and Heaven + Earth grade (HE grade) of red ginseng. HE-shape ginseng rate showed significant positive correlation (P=0.0l) with HE grade rate.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.341-348
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• 2018

To investigate the effect of light sources on the growth and photosynthesis of the dwarf apple rootstock M.9 for the production of standard seedlings, the plants were cultivated in a controlled environment for 6 weeks. The sources of light are six treatments [Red (R), Blue (B), White (W), RBUV (R7B3 containing UV-A), RBW (R3B1W1), SMF (high pressure sodium + metal halide + fluorescent lamp) under $154{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Growth characteristics of apple seedlings varied depending on artificial light source at 3 weeks and 6 weeks. The plant height of apple seedling was high in the R, RBUV, RBW, and SMF light sources at 3 weeks, and in the R light at 6 weeks. There was no significant difference on stem diameter among the treatments at 3 weeks, but showed high in RBUV and RBW light at 6 weeks. Leaf number was the highest in RBUV light at 3 and 6 weeks. The chlorophyll content (SPAD value) was high in the B and RBUV light at 3 weeks, but it was not significant at 6 weeks. The growth rate to height of the R light (1.12mm/day) was the highest among the treatments, followed by RBUV, RBW, SMF, W and then B. Leaf area was the highest in RBUV and RBW lowest in B. Specific leaf area was high in W and fresh and dry weight were high in RBUV. The photosynthetic rate at 6 weeks was highest in the B and lowest in the R. Stomatal conductivity and transpiration rate were higher in the B and W compared to the other light sources. Therefore, we are considered that light sources for growth of dwarf apple rootstock M.9 seedlings are suitable the R, RBUV, and RBW light sources with a high mixing ratio of Red and Red +Blue.