• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.61-65
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• 2000

Effects of temperature, soil moisture level, flooding, and soil microflora on decay of root galls in club root disease of Chinese cabbage were examined in the laboratory. Number of days required for complete decay of root galls was 3 days at $32^{\circ}C$ or higher, 12 days at $16{\sim}20^{\circ}C$ and 28 days at $8^{\circ}C$. As soil moisture content goes up, root gall decay became faster resulting 3 days for complete decay under saturated moisture condition at high temperature of $32^{\circ}C$, and 8 days under the same moisture level at $24^{\circ}C$. Soil moisture effect was relatively low at $24^{\circ}C$ compared to $32^{\circ}C$. Stimulation of decay by soil flooding was not observed at $32^{\circ}C$ but became apparent at $12^{\circ}C$. Influence of soil microflora on root gall decay was negligiable. Based on these results, temperature appears to be the most important factor affecting root gall decay in soil. Root gall decay is thought to be affected more easily by other environmental factors under low temperature conditions. Maturity of resting spores of Plasmodioprora brassicae in root galls tended to increase as time prolongs during root gall decay. Density of the resting spores was lower in fresh root galls where their maturity was also low as compared to completely decayed root galls. Number of resting spores in completely decayed root gall was $6.5{\times}10^{6}/g$ tissue and its maturity was over 95%.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.155-162
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• 2018

Background: In ecosystem carbon cycle studies, distinguishing between $CO_2$ emitted by roots and by microbes remains very difficult because it is mixed before being released into the atmosphere. Currently, no method for quantifying root and microbial respiration is effective. Therefore, this study investigated the relationship between soil respiration and underground root biomass at varying distances from the tree and tested possibilities for measuring root and microbial respiration. Methods: Soil respiration was measured by the closed chamber method, in which acrylic collars were placed at regular intervals from the tree base. Measurements were made irregularly during one season, including high temperatures in summer and low temperatures in autumn; the soil's temperature and moisture content were also collected. After measurements, roots of each plot were collected, and their dry matter biomass measured to analyze relationships between root biomass and soil respiration. Results: Apart from root biomass, which affects soil's temperature and moisture, no other factors affecting soil respiration showed significant differences between measuring points. At each point, soil respiration showed clear seasonal variations and high exponential correlation with increasing soil temperatures. The root biomass decreased exponentially with increasing distance from the tree. The rate of soil respiration was also highly correlated exponentially with root biomass. Based on these results, the average rate of root respiration in the soil was estimated to be 34.4% (26.6~43.1%). Conclusions: In this study, attempts were made to differentiate the root respiration rate by analyzing the distribution of root biomass and resulting changes in soil respiration. As distance from the tree increased, root biomass and soil respiration values were shown to strongly decrease exponentially. Root biomass increased logarithmically with increases in soil respiration. In addition, soil respiration and underground root biomass were logarithmically related; the calculated root-breathing rate was around 44%. This study method is applicable for determining root and microbial respiration in forest ecosystem carbon cycle research. However, more data should be collected on the distribution of root biomass and the correlated soil respiration.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.7-11
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• 1996

This study was conducted to know the effects of light intensity and temperature on growth of V. fauriei plants. Photosynthesis of V. fauriei had highly significant relations to light intensity and temperature in a quadratic regression model, from which the optimum light intensity and temperature for the plant growth were estimated to be 40,000lux and $17.7^{\circ}C.$ Root was produced less by shading at Jinbu where is located in alpine region, but root yield is increased by shading at Umsong where is located in plane region. Roots were produced more in Jinbu than in Umsong. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was $20.3^{\circ}C.$

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.274-274
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• 2017

Temperature has an adverse effect for potential growth and development of Codonopsis lanceolata. The present study examined the responses of growth, yield and mineral element contents under temperature variables in C. lanceolata. Plant height exhibited the best result as being 2 m or higher the open field culture, while the growth is the most restricted in the $30^{\circ}C$. The open field culture also had the largest number of leaves in the early stage of growth. The number of leaves and the height tended to be increased with the temperature of $20^{\circ}C$ and $25^{\circ}C$. The number of branches showed no significance as 32 branches and 26 branches in open field culture and $20^{\circ}C$, respectively. The smallest number of branches was observed in the $30^{\circ}C$ with 15 branches. The leaf color recorded the lowest value in the open field culture unlike the growth above the ground. But all other temperature had no significance with the leaf color value between 50.0 and 52.6. The elevated temperature induced the thinner and shorter diameter and length of root. However, the root diameter was not significantly changed with the change of 1.8 cm and 2.1 cm at open field culture, with $20^{\circ}C$ and $25^{\circ}C$, respectively. The fresh weights of the primary root and lateral roots were 6.3 g and 3.1 g, respectively, at the high temperature. The result showed the thickening of the lowest part under the ground as restricted. The fresh weights of the main root and lateral root were the highest on the open field culture, 20.6 g and 12.2 g, respectively. The contents of cellulose were the highest as 4.41% in the $20^{\circ}C$, followed by the open field culture, $25^{\circ}C$ and $30^{\circ}C$. The higher temperature reduced the contents of cellulose. Moreover, P showed higher ratio in the high temperature while Ca and Mg exhibited the higher ratio towards the low temperature. On the contrary, minor quantity (less than 1%) of mineral nutrients was observed towards all temperature variables.

• Food Engineering Progress
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• v.23 no.1
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• pp.69-75
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• 2019

This study investigated the effects of blanching conditions on the quality characteristics of burdock, lotus root, and garlic scape. The selected plants were blanched at varying temperatures (70-100℃) for 1-5 min, and moisture content, shear force, color, and total microbial count were analyzed. Burdock exhibited browning discoloration when it was blanched at a relatively low temperature (70-80℃). In addition, thermal tenderization of burdock was not evident in the blanching conditions adopted in this study. Blanching affected the tenderness and moisture content of lotus root without deteriorative discoloration. In particular, low temperature blanching (80℃) was favorable to blanching lotus root. Alternately, thermal tenderization of garlic scape was possible by blanching at 80-100℃ for 3-5 min, while discoloration of the blanched garlic scape dominated at high-temperature blanching (100℃). Consequently, the result indicated that low temperature for a long time (80℃ and 3-5 min) provided a better blanching condition for lotus root and garlic scape than high temperature applied at a short time (100℃ and 1-3 min).

• The Korean Journal of Ecology
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• v.24 no.2
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• pp.87-91
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• 2001

The response of respiration rates of root, Ao layer and mineral soil to varying environmental factors was studied in Popuius maximowiczii stand (25-year-old) during the growing season of 1997. Soil temperature showed a pronounced seasonal course, in contrast to soil moisture. The mineral soil respiration was high in August, and root and Ao layer respiration, were high in July. An exponential equation best described the relationships between soil temperature and mineral soil respiration, and total soil respiration (r＝0.95 and 0.92, p＜0.001), respectively. In P. maximowiczii stand, soil respiration rates were reduced by about 19% after removal of the Ao layer, and by about 30% after removal of living root. Therefore, mineral soil respiration seemed to contribute gretly to the total soil respiration (50%).

• Korean Journal of Medicinal Crop Science
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• v.16 no.4
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• pp.211-217
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• 2008

To find up using of more efficient white ginseng, white ginseng was dried on various temperature (70, 80, 90,100, 110, 120, 130 and $140^{\circ}C$) with far-infrared drier and analyzed the composition of ginsenoside, carbohydrate, organic acid content and color. The type of ginseng shape was sliced and dried main and fine root, separately. As heating temperature increased, total ginsenoside content increased on main root, its content was the highest at $130^{\circ}C$, while decreased on fine root. Soluble carbohydrate content was the highest at $70^{\circ}C$ both on main and fine root. Increase of Re, Rc and Rb2 content was increased more high at $130^{\circ}C$, especially. But on fine root, content of Rg1, Rg3, Rf and Rb3 was increased and Re, Rc,Rb1 and Rb2 were decreased by the increased of temperature. As heating temperature increased, lightness of both main and fine root were decreased. Redness and yellowness of both main and fine root was increased to $120^{\circ}C$ and $100^{\circ}C$, respectively and decreased over this temperature.

• Journal of Ginseng Research
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• v.5 no.1
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• pp.73-84
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• 1981

Effect of environmental factors and host on the growth and outbreak of various ginseng diseases was reviewed Environmental lectors included hydrogen ion concentration, moisture content, temperature, nutrition, and microbiol populations. Age of the ginseng plants in relation to several ginseng disease occurrence was also included in order to formulate the effective control measure for ginseng diseases. Damping-off caused by Rhizoctonia, Pythium, and Phytophthora, greymold by Botrytis, sclerotinia by Scleretinia, and phytophthora blight caused by Phytophthora were usually prevalent during the early growing season of ginseng when temperature is below 20$^{\circ}C$, while anthrac se caused by Colletotrichum, alternaria blight by Alternaria, and bacterial soft rot by Erwinia were so during the latter growing season when temperature is above 25$^{\circ}C$. However, the root rot incited by Fnarium and Cylindrocarpon caused severe damages throughout the growing season. Growth range of the temperature for a pathogen was highly related to the corresponding disease outbreak. Hydrogen ion concentration was highly related to the outbreak of sclerotinia, root rot, and red rot. Most severe outbreak of those diseases where the soil acidity was pH 4.7, pH 6.5- 7.5, and pH6.0-6.5, respectively. Nitrogen content in the soil was also related to outbreak of root rot and red rot. More red rot occurred where NH,-nitrogen is above 30 ppm and more root rot obtained when excessive nitrogen fertilizer applied. Yellow necrosis apparently was related to magnesium especially its ratio with potassium or calcium content in a soil. Fusarium Population showed significant .relations to missing rate of ginseng Plants in a Implanting ginseng field, while that of total bacteria showed similar relations in all ginseng field, However, in six year old ginseng fields, the more the Streptomyces population was, the less the Fusarium obtained. Consequently, less missing rate observed in a field where Streptomyces population was high. Damping-off, root rot, Rhytophthor a blight were mose severe on the nursery and on 2-3 years old ginseng plants, whereas sclerotinia, and grey cod, alteraria blight, anthracnose were severe on 4-6 years old ginseng plants. Root rot caused by Fusarium and Erwinia, however, was also severe regardless of the age of the plants when the roots were injured. Therefore, for the effective control of ginseng root rot most careful control of the disease during the early year should be rendered.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.286-291
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• 2022

The effect of root-zone local cooling on seedling growth of tomato was investigated. Lower pipe cooling was used for local cooling of the root zone, and the root zone temperature was set at 20 and 25℃. There was no difference in plant height, root length, and leaf number according to local cooling temperature. Leaf area, fresh weight, dry weight, and chlorophyll content of the shoot and root was higher in the 25℃ than those of 20℃ at 28 DAS. These results showed that cooling for seedling growth of tomato 25℃ is sufficient considering energy efficiency. This study will be helpful in the development of local cooling technology that can reduce the energy required for cooling during the production of tomato seedlings in the high temperature season.

• Journal of Biosystems Engineering
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• v.34 no.3
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• pp.190-196
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• 2009

The temperature of root zone is known as an important factor for the growth of crops and reduction of energy in greenhouse. The purpose of this study was to design the solar energy supply system to keep the optimum condition of root zone by soil warming. As a result of this study, soil warming compared with no warming changed on a large scale temperature rise effect by depth of soil. The greenhouse's inner temperature have an effect on the temperature of surface up to 15 cm, rised to about 1 hour after warming. In case of the temperature fluctuation, soil temperature was about $12^{\circ}C$ up to 15${\sim}$25 cm and it was $13.4^{\circ}C$ at greater depths. This results showed that the position of root zone was very different after 3 weeks of growth.