• Korean Journal of Environmental Agriculture
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• v.15 no.3
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• pp.325-334
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• 1996

Pepper plants were flooded at 0, 5, 10 and 15cm at seedling stage under the condition of greenhouse. Treatment of flooding times are 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. Plant height, number of leaves, shoot and root fresh weight were not recovered the flooding damages regardless of flooding time and depth. Pepper plant died in flooding depth of 5cm or more for over 48 hours. Plants in fallen leaves were found at more than 5cm depth and 6 hours of floodings. Photosynthesis and respiration rate decreased in the 5cm flooding depth or more for 24 hours. Chlorophyll content and root activity decreased for 12 hours or more at all the flooding depth. Also, diffusion resistance of stomata cell increased as increased flooding time and depth. Diseases occurred remarkably in proportion to the depth and hours of flooding treatment. It was not possible to control the desease by fungicide, also then was no effects of foliar spray of urea. Weight of fruit per plant not decrease by the 12 hours of 0cm and the 6 hours of 5cm flooding but decreased at deeper and longer flooding. Average weight of a fruit increased. The yield could not expected in the depth of 5cm or more for over 48 hours, There was significant positive correlation between all the investigated characteristics of growth and yield. There was, however, negative correlation between number of leaf and diffusion resistance of stomata.

• The Plant Pathology Journal
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• v.34 no.4
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• pp.316-326
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• 2018

The effect of simulated climate changes by applying different temperatures and $CO_2$ levels was investigated in the Blumeria graminis f. sp. tritici/wheat pathosystem. Healthy and inoculated plants were exposed in single phytotrons to six $CO_2$+temperature combinations: (1) 450 ppm $CO_2/18-22^{\circ}C$ (ambient $CO_2$ and low temperature), (2) 850 ppm $CO_2/18-22^{\circ}C$ (elevated $CO_2$ and low temperature), (3) 450 ppm $CO_2/22-26^{\circ}C$ (ambient $CO_2$ and medium temperature), (4) 850 ppm $CO_2/22-26^{\circ}C$ (elevated $CO_2$ and medium temperature), (5) 450 ppm $CO_2/26-30^{\circ}C$ (ambient $CO_2$ and high temperature), and (6) 850 ppm $CO_2/26-30^{\circ}C$ (elevated $CO_2$ and high temperature). Powdery mildew disease index, fungal DNA quantity, plant death incidence, plant expression of pathogenesis-related (PR) genes, plant growth parameters, carbohydrate and chlorophyll content were evaluated. Both $CO_2$ and temperature, and their interaction significantly influenced powdery mildew development. The most advantageous conditions for the progress of powdery mildew on wheat were low temperature and ambient $CO_2$. High temperatures inhibited pathogen growth independent of $CO_2$ conditions, and no typical powdery mildew symptoms were observed. Elevated $CO_2$ did not stimulate powdery mildew development, but was detrimental for plant vitality. Similar abundance of three PR transcripts was found, and the level of their expression was different between six phytotron conditions. Real time PCR quantification of Bgt was in line with the disease index results, but this technique succeeded to detect the pathogen also in asymptomatic plants. Overall, future global warming scenarios may limit the development of powdery mildew on wheat in Mediterranean area, unless the pathogen will adapt to higher temperatures.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.281-287
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• 2012

This experiment was conducted to investigate the effect of various type of Magma seawater (MSW) concentrations on plant growth and useful mineral contents in Bletilla striata. In the RO (Reverse Osmosis) and ED (Electronic Distal) treatment, hardness of medium was poored in 3.0 g/L gelrite but increased in 8.0 g/L plant agar, 38,000 and $2,000g/cm^2$ respectably. We analyzed the morphological and physiological characteristics differences of B. striata treated various MSW. Survival frequency of plant and growth (shoot length, shoot diameter, root length, root diameter, shoot/root ratio) were significantly increased in RO and ED treatment at 50% and 10%, especially. Chlorophyll contents in ED treatments were higher than those in control and RO treatment. The content of strontium (Sr) in 20, 50, 75, 100% ED treatment, were higher than those in the control and RO, ED 1, 5, 10% treatment. These results showed that treatment of ED with the range of 20~100% could be used to supply the strontium enriched orchid plant. It is considered that MSW may be applied for use in Magma seawater to promotion of growth and produced functional plant.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.2
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• pp.70-78
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• 2009

Remote sensing technique in agriculture can be used to identify chlorophyll content, biomass, and yield caused from N stress level. This study was conducted to evaluate biomass, N stress levels, and yield of tobacco (Nicotiana tabacum L.) under sand culture in a plastic film house using ground-based remote sensors. Nitrogen rates applied were 40, 60, 80, 100, 120, and 140 percent of N concentration in the Hoagland's nutrient solution. Sensor readings for reflectance indices were taken at 30, 35, 40, 45, 50 and 60 days after transplanting(DAT). Reflectance indices measured at 40th DAT were highly correlated with dry weight(DW) of tobacco leaves and N uptake by leaves. Especially, green normalized difference vegetation index(gNDVI) from spectroradiometer and aNDVI from Crop Circle passive sensor were able to explain 85% and 84% of DW variability and 85% and 92% of N uptake variability, respectively. All the reflectance indices measured at each sampling date during the growing season were significantly correlated with tobacco yield. Especially the gNDVI derived from spectroradiometer readings at the 40th DAT explained 72% of yield variability. N rates of tobacco were distinguished by sufficiency index calculated using the ratio of reflectance indices of stress to optimum plot of N treatment. Consequently results indicate that the reflectance indices by ground-based remote sensor can be used to predict tobacco yield and recommend the optimum application rate of N fertilizer for top dressing of tobacco.

• Journal of the Korean Society of Tobacco Science
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• v.15 no.1
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• pp.63-74
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• 1993

Changes in the amount of ribulose 1, 5-bisphosphate carboxylase/oygenase(=RuBisCO) protein, namely fraction I protein, and the protease activity were determined in the 10th leaf of tobacco(Nicotiana tabacum, var. Ky-57) from 10 days after emergence through senescence at 5 days interval. The amount of RuBisCO per deveined leaf rapidly increased during the early growing season, reached a maximal quantity at the around 20 days after leaf emergence, when the leaf has gone through its most rapid expansion, and began gradually to decrease till 30 days after leaf emergence, thereafter significantly declined to 45 days that the leaf has been dried up partly. The pattern of the ratio of RuBisCO protein to soluble protein in quantity changed similar to that of RuBisCO contents in a leaf, that was 43%, 60%, and 21% at the around 10 days, 20 days, and 45 days, respectively. And RuBisCO contents was linearly correlated with the concentration of chlorophyll(r=0.98) throughout the life span of the leaf. So, it was assumed that the leaf color can be a useful indicator for judging whether RuBisCO contents higher or not in tobacco leaves without homogenization. On the other hand, the protease activities for degradation of casein were assayed at pH 5.5. 7.0. and 8.5 with crude extracts desalted on Sephadex G-25. The highest caseolytic activity was found at pH 5.5 throughout the life sawn of the leaf. Also, the activity at 5.5 became gradually to increase from 30 days after leaf emergence, when RuBisCO protein had became to disappear and remarkably increased in the last stage of senescence, although nitrogen contents of the leaf had reached low levels. The caseolytic activity at pH 5.5 was in negative correlation with RuBisCO contents throughout the life span of the leaf, but not in lineality between them. In other words, the caseolytic activity increased in a rapid exponential manner when RuBisCO contents had reached some low levels. These results showed that the leaf age, namely harvesting time, is a very important factor for the production of the tobacco leaf containing higher RuBisCO protein. It was concluded that the practical harvesting time is between 20 days and 30 days after the leaf emergence from the present results.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.197-203
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• 1999

The albino plants of tobacco (Nicotiana tobacum L. cv. BY-4) were isolated from seed populations that were induced by heavy-ion ($^{14}N$) beam irradiation to proembryo and the in vitro growth and differentiation have been characterized. The in vitro cultured albino plants showed significant reduction of chlorophyll content and possessed larger number of stomata on both upper and lower epidermis than that of wild-type plants. Stem growth of the mutants remained dwarfed, however, the internode recovered its normal length after GA$_3$ treatment (10.0mg/L) on the MS medium containing sucrose under continuous light. When explants of leaf blades of albino plants were cultured, multiple shoots formed directly on MS medium containing 1.0mg/L of BAP or kinetin and a large number of calli were induced on the MS medium containing 1.0mg/L NAA or 1.0 mg/L 2,4-D. The albino calli regenerated multiple albino plantlets in the MS medium containing 0.1mg/L NAA + 1.0 mg/L BAP. No significant differences between the wild-type and albino plants were detected in the multiple shoot induction, callus formation from the explants and the plantlets regeneration from calli. In addition, albino plants have a similar organogenesis Pattern to that of the wild-type in the media with different combinations of NAA (0 to 5.0mg/L) and BAP (0 to 5.0mg/L) treatment. These results indicate that the albino mutant has the same normal regeneration ability as that of wild-type, although the mutant has lost functions in photosynthesis, such as pigmentation.

• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.275-279
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• 2001

The contents of chemical components such as total nitrogen, total amino acid, chlorophyll, vitamin C and free sugar were somewhat higher in $CO_2$ and $N_2$ gas treatment than those of other treatment. However, the contents of tannin and caffeine did not show any different in the 5 treatments. ${\gamma}-aminobutyric$ acid(GABA) and alanine accumulated in tea leaves under anaerovic condition. The content of GABA acid with ${CO_2\;and\;N_2}$ gas treatment was higher 8-6 times with values of ${264{\sim}215mg/100g}$ than in control (35mg/100g). The scores of sensory test was not different between anaerobic treatment and control. Consequently, tea mading within ${N_2\;and\;CO_2}$ gas treatment after plucking was considered to be the best green tea in terms of functional nature as well as taste nature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.307-314
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• 1984

One hundred winter wheat cultivars obtained from the world collections in Korea were planted in 1982. Stomatal frequency of flag leaf of these cultivars were measured, and among these 21 cultivars which showed different stomatal frequency were selected to investigate the relationship of their stomatal frequencies and other characters such as culm length, heading date and characters related to leaf. Stomatal frequency of flag leaf of 100 cultivars different significantly, ranging from 51 to 90 stomata mm$^{-2}$ for the adaxial and 35 to 65 for the abaxial surfaces of leaf. Stomatal frequency was always greater on the adaxial than on the abaxial surface. Mean ratios (adaxial/abaxial) were 1.5 for the flag leaf and 1.3 for the from second to fouth leaves. Among 21 cultivars examined, stomatal size which measured guard cell length varied from 38.5 to 46.6$\mu$ for adaxial surface and from 39.4 to 49.4$\mu$ for abaxial. A negative correlation was obtained between stomatal frequency and its size. Stomatal frequency decreased from flag (L$_1$) to lower leaves, progresively. Stomatal frequency on L$_1$ sheath was compared to those on L$_3$ and L$_4$ abaxial surface of leaf. More stomatal frequency on top and center of adaxial surface showed than that on basal part of a leaf but the abaxial surface resulted in reverse of adaxial one. Cultivars with high stomatal frequency on flag leaf showed higher stomatal frequency on the other leaves and sheaths. Positive correlation between stomatal frequency and other characters such as, culm length, heading date and chlorophyll content showed statistical significance, whearas it revealed the negative correlation of stomatal frequency with leaf weight, leaf area and stomatal aperture. However, no relation appeared between stomatal frequency and leaf vein.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.157-162
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• 1987

The study was carried out to investigate the effects of light intensity, temperature and seasonal trends on the photosynthesis as well as the physiological characteristics of Panax species and cultivars. Four-year-old plant of Violet-stem variant, Yellow-berry variant, Mimaki and Russian ginseng of Panax ginseng C. A. Meyer and American ginseng of Panax quiquefolium L. were used for study. These Panax species and cultivars were cultivated under the straw shading. The light saturation point of leaves in Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 15,000 lux, but that of Russian ginseng was 10,000 lux. The optimum air temperature on the phtosynthesis of Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 20$^{\circ}C$ but that of Russian ginseng was 15$^{\circ}C$ under 15,000 lux. The photosynthetic rates were increased in order of Russian ginseng, Mimaki, Yellow-berry variant, Violet-stem variant and American ginseng. The respiration rates of ginseng leaves were increased according to the increasing of temperature, but it was not different among Panax species and cultivars. Stomata frequency of American ginseng was highest, that of Russian ginseng lowest, while the length of stomata was reverse. The total chlorophyll content of American ginseng and specific leaf weight of Mimaki were higher than other ginseng cultivars. The root weight of American ginseng was heavier than others, but that of Russian ginseng was lighter. The num ber of leaflets per plant of 2-year-old plant and the root weight of 6-year-old plant were increased in order of Russian ginseng, American ginseng, Mimaki, Yellow-berry variant and Violet-stem variant.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.3
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• pp.1-12
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• 2018

This study was conducted to obtain a reliable result assessing proper amount of solid swine manure for the growth of Deutzia crenata seedlings. Seedling growth dry weight, chlorophyll content inorganic nutrients and soil chemical properties were investigated. 1. When treated with solid swine manure, seed germination rate was highest on the control. However, germination rates tended to decrease when treated with swine manure at high concentrations. 2. The growth of seedlings treated with swine manure was always higher than that of in control. At the 1.0% of swine manure treatment, the growth rate of the seedlings was highest. 3. Seedling dry weight was highest at the 1.0% swine manure treatment. The amount of inorganic nutrients absorbed by the seedling was generally high with the 1.0% treatment, declined sharply with the 2.0% treatment. 4. For the planting soil of Deutzia crenata, the higher the concentration of swine manure, the lower the soil pH. However, nitrogen, available P, K, Na, Mg and Ca contents in the soil have increased with higher concentrations.