• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.133-137
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• 2006

Evaluation of physiological performance of trehalose-producing transgenic rice line was conducted to investigate drought tolerance at early growth stage. Under artificially induced drought condition of 8% polyethylene glycol 6000, this transgenic rice line had leaf photosynthetic rate of 11.08 uml CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8.38 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -1.12 MPa after 96 hours of treatment. Nakdongbyeo, the parent of this tyansgenic rice line, had photosynthetic rate of 15.42 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 8,04 mmol $H_2O$ $m^{-2}s^{-1}$ and leaf water potential of -0.88 MPa. The other variety used in this experiment for comparison, IR 72, showed higher values than both tyansgenic rice line and variety Nakdonbyeo on all three parameters; leaf photosynthetic rate of 20.61 $\mu$mol CO$_2$ $m^{-2}s^{-1}$, leaf transpiration rate of 12.88 mmol $H_2O$ $m^{-2}s^{-1}$, and leaf water potential of -0.82 MPa. So this transgenic rice line did not show superior performance in leaf transpiration rate, leaf photosynthetic rate and leaf water potential compared to variety Nakdongbyeo. This result along with visual observation on leaf rolling and drying during the experimental period indicated poor physiological performance of this transgenic rice line. Further studies on metabolic status of stress-induced trehalose, along with study on physiological response of this transgenic rice line during drought stress would shed more light on overall physiological performance of this transgenic rice line.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.293-297
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• 2011

This experiment was conducted to elucidate the effects of mulching materials and removing time of the transparent polyethylene (PE) film on the growth of garlic at Uiseong experimental field, Korea. The experimental mulching materials comprised of transparent polyethylene film (0.025 mm) and net polyethylene (NPE). Plant height and leaf number of garlic were highest at PE treatment when the PE removing date was March 18 and this treatment also promoted the no. of cloves. Length of leaf sheath and bolting rate were highest and bulb weight loss rate was lowest at PE + NPE treatment when the PE removing date was March 18. But clove number was the lowest in this treatment compared to conventional PE film treatment. Conventional mulching method accelerated secondary growth rate but bulb weight loss was vice versa. There were statistically no differences in bulb diameter among treatments but conventional treatment positively focused on bulb diameter. Whenever PE film remove can suppress weeds compared to no mulching treatment but the dry weight of weeds were increasing trends as the removal dates of PE film were delayed. Transparent PE or PE + NPE treatments can be recommended to grow best quality garlic when PE film removing date is March 18.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.63-67
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• 1999

Growth rate and osmolyte accumulation of L. monocytogenes were measured at the varying concentrations of NaCl. L. monocytogenes accumulated glycine betaine and glutamate intracellularly when grown under osmotic stress by NaCl, and the amounts of them increased as the concentration of NaCl was increased. They were 685 and 345 nmol/mg protein, respectively, when grown in the BHI supplemented with 4% NaCl. In order to inhibit L. monocytogenes effectively, both NaCl and Morus alba L. leaf extract were supplemented in TSB, and antibacterial effect of those supplements on L. monocytogenes was tested. Growth of L. monocytogenes grown in TSB supplemented with 2% NaCl and 100 ppm M. alba leaf extract decreased by 10 times in CFU/ml unit comparing to the growth of control. When grown in TSB, supplemented with 2% NaCl plus 500 ppm M. alba leaf extract and 2% NaCl plus 1,000 ppm M. alba leaf extract, growth of L. monocytogenes decreased by $10^5\;and\;10^8$ times in CFU/ml unit, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.292-298
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• 1997

To compare the growth pattern of ginseng plant under between conventional shading(light transmittance rate 3％) and polyethylene net shading(light transmittance rate 10％), the distribution of leaf area, specific leaf weight (S. L. W), leaf and stem dry weight and changes in light intensity were investigated in 2, 4 and 6 year old ginseng plant populations. Light transmittance rate(L.T.R.) was 3％ at front line, 2％ at middle line and 1.5％ at rear line under conventional shading but it was 12, 10 and 8％ under polyethylene net(P.E) shading, respectively. In 2 year old population, there was a little difference in the growth characteristics investigated between conventional and P.E. shading. In 4 year old field, the leaf area, stem and leaf dry weight decreased in large amount in the order of middle, and rear line on ridge under conventional shading, but with a little difference under P.E. shading. And these trends enlarged in 6 year old field with appearance of a large part of shoot over furrow from ridge planted ginseng. Root yield index was much lowered at the rear 3rd, 4th and 5th line of the conventional shading bed, but there was no yield difference among lines except 5th lines under the P.E. shading with higher yield by 28％ than conventional shading.

• Journal of Environmental Science International
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• v.24 no.1
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• pp.55-64
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• 2015

The dry weight of mother plants' leaves had the highest increase rate in both NS (single-use) and NS+EM (mixed-use) mixed with NS 0.8 (customary use). In seafood amino acid fertilizer (SAF) application, the increase rate was highest in SAF solution at a 300-fold dilution. Mother plants' crown diameter, plant height, leaf length, leaf width, petiole length and leaf number showed the greatest growth amount when NS 0.8 (customary use) was mixed to NS (single-use) or NS+EM (mixed-use) solution. The growth was highest in SAF solution diluted 300 folds, but lowest in SAF solution diluted 100 folds. Of all inorganic nutrients, excluding sulfur, total amount of nitrogen, available phosphorus, potassium, calcium and magnesium had the highest increase rate in both NS (single-use) and NS+EM (mixed-use) with the treatment of NS 0.8 (customary use). Total nitrogen, in particular, was increased by 3.1% in NS 0.4, 6.0% in NS 0.8, and 4.5% in NS 0.8 with the application of NS+EM at a 500-fold dilution compared to NS alone. Total nitrogen amount showed the highest increase rate in SAF solution diluted 300 folds. Total nitrogen, available phosphorus, calcium, magnesium and EC in soils applied with culture solutions (NS, NS+EM) had increasing tendencies after fertilizer application. The results were comparable to those of SAF treatment. The increase rate of each inorganic nutrient composition declined in soils applied with NS+EM solution diluted 500 folds compared to NS alone.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.181-188
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• 2003

Frequencies of each size class, annual change of tuber state and above ground/belowground rate in sect. Pes-gallinaceua group of Corydalis (Fumariaceae) were studied to clarify spring ephemeral´s growth characteristics from 1999 to 2000 in Namhansansung area. Shoot grew from the tuber corresponding with soil thawing in the early growth season, and the deeper tuber was located in soil, the later shoot germinated. Shoot appeared in middle March and died early in May, and the period of total growth season was 45 days. Frequencies were 40% (in total dry weight) or 53% (in tuber´ dry weight) in the smallest size class, and 93% (in total dry weight) or 96% (in tuber´ dry weight) below medium size, therefore, almost all of plants were small. Specific gravity of tuber (SGT) gradually decreased from late growth season to the time that leaf unfolded in next year. At this time, the value of SGT was 0.14. Thereafter, SGT increased to 0.42 at withering time of aboveground part. During growth season, the SGT of flowering plants was lower than that of non-flowering plants. And SGT difference between flowering plants and non-flowering plants was significant at 1% level. In the late growth season, SGT decreased along the increase of tuber volume. The tuber volume roughly increased along the leaf area but there was no a conspicuous trend. Shoot/tuber rate had nothing to do with tuber volume. SGT decreased and leaf area increased along the tuber dry weight, and tendencies of increase or decrease were conspicuous. Therefore, the smaller the plants were, the larger organic matter accumulated in tuber during a growth season. Shoot/tuber rates were various along each plant.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.38-45
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• 1982

To determine the optimum light intensity for growth of ginseng plants, change of temperature, moisture content in son, occurrence alternaria blight, defoliation rate, chlorophyll contents, and growth of shoots and roots were investigated under different light intensity such as 5%, 10%, 20% and 30% light transmittance rare(L.T.R.). The results obtained were as follows. 1. Maximum temperature under the shading was increased as the increase of light intensity, whereas soil moisture content decreased 2. As the increase of light intensity, stem and Peduncle length, leaf area, and chlorophyll contents decreased significantly but length and width of the leaf was not significant, while stem diameter, special leaf weight and chlorophyll a/chl. b ratio increased 3. Stem color was shown dark purp!e as the increase of light intensity. 4. Photosynthesis during the day was highest at 9 A.M. and decreased as time passed in all plots. The means of photouynthesis during the day showed in the order of 20%, 10%, 30%, 5% L.T.R., and optimum light intensity for highest photosxthesis was 18.4% L.T.R. by theoritical equation. 5. It was showed a tendency that alternaria leaf blight of ginseng plants was increased as the increase of light intensity. 6. Defoliation rate of ginseng plants was increased as the increase of light intensity, especially all plants were defoliated by late June without shading. 7. Yield percentage of the rear line was increased as the increase of light intensity. Root weight per plant showed in the order of 20%, 10%, 30%, 5% L.T.R., and optimum light intensity for the best yield was 18.5% L.T.R. by theeritical equation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.93-101
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• 2008

The effects of $CO_2$ enrichment on growth of maize (Zea mays L.) were examined. Parameters analyzed include growth characteristics, yields, photosynthetic rates, evaporation rates and photosynthesis-related characteristics under elevated $CO_2$. The plants were grown in growth chambers with a 12-h photoperiod and a day/night temperature of $28/21^{\circ}C$ at the seedling stage and $30/23^{\circ}C$ from the silking stage. The plants were exposed to two elevated $CO_2$ of 500, 700ppm and ambient levels (350 ppm). Chalok 1 and GCB 70 germinated three days after seeding, and germination rates were faster in the elevated $CO_2$ than the control. Germination rates displayed significant differences among the $CO_2$ treatments. At the seedling stage, leaf area, top dry weight, and photosynthetic rates, and plant height indicated positive relationship with elevated $CO_2$ concentrations. At the $5{\sim}6$ leaf stage, $CO_2$ concentration also indicated positive relationship with plant height, leaf area, top dry weight, and photosynthetic rates. At the silking stage, increased plant height of Chalok 1 was noted in the $CO_2$ treatments compared to the control. No significant differences were noted for GCB 70, in which leaf area decreased but photosynthetic rates increased progressively with $CO_2$ concentration. Stomatal aperture was a little bigger in the elevated $CO_2$ than the control. $CO_2$ concentration was negatively related to stomatal conductance and transpiration rates, resulting in high water use efficiency.

• Journal of Biosystems Engineering
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• v.36 no.3
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• pp.211-216
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• 2011

According to the result of the first report and the second report of this study, it was expected that soil heating in a protected cultivation in winter season would affect the initial growth and development of fruit. Based on the result of previous study, we compared height, leaf number, leaf area, fruit weight, crop growth rate (CGR), features and quantity of cucumber for 3 months after planting between the soil heating group and the non-heating group. The result were summarized as follows: The height, leaf number, leaf area and fruit weight of cucumber in the soil heating group were 12.5%, 14.6%, 21.4% and 22.8% higher, respectively, compared to those of cucumber in the non-heating group. Although both the soil heating group and the non-heating group similarly showed an increasing pattern in CGR after transplanting, the soil heating group showed the increased CGR by 12.1% compared to that of the non-heating group. The quantity of cucumber in the soil heating group was about 26% higher than that of the non-heating group. It is assumed that the activation of initial growth and development of fruit in the heating group resulted in the increase of quantity.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.60-66
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• 2022

This study was conducted to investigate growth characteristics of paprika seedlings according to various qualities of LED light (red : blue = 10 : 0, red : blue = 8 : 2, red : blue = 2 : 8, white). Plant height and stem were significantly longer or thicker as red light ratio increased. Leaf area of paprika seedlings with red light was larger or no significant differences in a mixed light of red and blue. Dry weight of seedling was in the same with the result of leaf area. Seedlings with White light was significantly less than others in all characteristics. As red light ratio was increased, relative growth rate increased. As blue light ratio was increased, the net assimilation amount increased. Considering plant height, leaf area and production ability of dry matter per unit leaf area, the using mixed red and blue lights was suitable, especially at a mixed red : blue = 8 : 2.