• Horticultural Science & Technology
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• v.28 no.5
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• pp.783-789
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• 2010

The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

• Asian Journal of Turfgrass Science
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• v.15 no.4
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• pp.169-179
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• 2001

This study was conducted to determine the effect of root zone cooling on growth and quality of turfgrasses including Kentucky bluegrass (Poa pratensis L.‘Nuglade’), perennial ryegrass (Lolium perenne L.‘Accent’), tall fescue (Festuca arundinacea Schreb.‘Pixie’), and Japanese lawngrass (Zoysia japonica Steud.) in simulated athletic field during summer season in Korea. Mineral contents in clippings of turfgrasses grown at different soil mixtures and temperatures were also analyzed. Root zone cooling (approximately 4~6$^{\circ}C$ lower than that of untreated-control) resulted in good uniformity, little disease incidence and higher level of chlorophyll contents in cool-season turfgrasses. The effectiveness of root zone cooling in protecting disease incidence from high temperature stress was the most manifest in perennial ryegrass compared to others. Fresh clipping weight in treatment of root zone cooling was increased approximately 2 times in Kentucky bluegrass and perennial ryegrass, and 2.5 times in tall fescue compared to those of control. There was higher growth rate in a soil mixture composed of 80% peat moss ＋10% sand ＋10% soil (v/v/v) than in that of 80% pea moss ＋20% sand (v/v), Mineral contents of N, P, K, Ca, and Mg in clippings of three species of cool-season turfgrasses were significantly increased in treat-ment of root zone cooling but this was not found in Japanese lawngrass. Results showed that root zone cooling has a benefit in keeping good quality and growth of cool-season turfgrasses in sports field under supraoptimal ambient temperature during summer season.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.33-38
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• 2006

This study was performed to provide basic rheological data of dandelion root concentrates in order to predict their processing aptitude and usefulness as functional foods material. The hot water and 70% ethanol extracts of dandelion root were concentrated at 5, 20, and 50 Brix, and their static viscosity, dynamic viscosity, and Arrhenius plots were investigated. Almost all hot water concentrates showed the typical flow properties of a pseudoplastic fluid, but evaluation using the power law model indicated that the 70% ethanol concentrates showed a flow behavior close to a Newtonian fluid. The apparent viscosity of hot water and 70% ethanol concentrates decreased with increasing temperature. Yield stresses of hot water and 70% ethanol concentrates by Herschel-Bulkley model application were in the range of 0.026 - 1.368 Pa and 0.022 - 0.238 Pa, respectively. The effect of temperature and concentration on the apparent viscosity was examined by Arrhenius equation. The activation energies of hot water and 70% ethanol concentrates were in the range of $8.762-23.778{\times}10^3\;J/mol{\cdot}kg$ and $3.217-20.384{\times}10^3\;J/mol{\cdot}kg$ with increasing concentration, respectively. Storage (G') and loss (G") moduli were generally increased with increasing frequency. For the 70% ethanol concentrates, G" predominated over G' at all applied frequencies and so they showed the typical flow behavior of a low molecular solution. However, for the hot water concentrates, G' predominated over G" at more than 1.9 rad/sec (cross-over point) and so they showed the typical flow behavior of a macromolecular solution.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.129-132
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• 1988

Ginseng is cultivated in Korea. Japan. China. the Soviet Union and North America. Studies of the macroclimate of each of these producing areas shows that ginseng has certain requirements for production. In each producing area the microclimate is modified in different ways. Comparisons of recent research data from North America. Korea and China is presented in order to define. more precisely. the various microclimate requirements for ginseng production. These include studies of light interception as influenced by different shade materials. In North America. wood. woven black polypropylene and knitted polyethylene shade are used. whereas in China. dried grasses are bound together in layers with wire and polyvinylchloride is inserted between the layers. The influence of these various shade materials in terms of crop grow1h and root yield are presented. The major effect of temperature seems to be on root growth. During much of the growing season optimum temperatures for root grow1h are not reached. Growth analysis data for different age plants are being used to show the effects of different soil temperature regimes on distribution of dry matter between the shoot and root.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.57-64
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• 1991

This experiment was conducted to elucidate the effect of plant growth regulators (PGR) on the root -mat formation of infant seedling (8- to 10-day-old seedling) of rice in machine transplanting. The rice seeds of Odaebyeo were socked in water with different concentrations of PGRs for 48 hours at room temperature. Seeding rate was 220 g per seed tray (30x60x3cm). Metalaxyl (25% wettable powder) was used for a fungicide. Generally, the metalaxyl-treated seeds markedly promoted the root growth of the rice seedling, while tetracy-cle, pachlobutrazol and NTN -821 reduced the seedling height and root length, and thickened the shoot diameter at higher concentation levels. Tetracycle decreased root length of the rice seedlings but increased root number per seedling, and root-mat formation was poor. Whereas, metalaxyl concentrations of 200 and 1,000 ppm markedly increased root length and number of root hairs without decreasing root number, thus root-mat formation was excellent. The optimum concentration of metalaxyl seed treatment to increase the root-mat formation of infant seedling of rice was about 200 ppm. Metalaxyl seed treatment could be advanced one to two days of the duration of root-mat formation compared with control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.216-221
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• 2004

Treatment effect of benzyladenopurine (BA) used to block the lateral roots formed on soybean sprouts should be influenced by its applying methods. This study was done to check the effects of temperature and period from seed imbibition into 2 ppm BA solution to the first watering for sprout culture on growth and morphology of soybean sprouts. Imbibed three cultivar (cv. Pungsannamulkong, Sowonkong and Junjery) seeds for 5 houys into 2 ppm BA solution were placed under different temperatures (AT; 20, 30, $40^{\circ}$) and periods (AP; 0, 1, 2, 3, 4 hours). On the 6th day, the soybean sprouts were classified by 4 categories on the base of hypocotyl length; ＞7cm, 4 to 7cm), ＜ 4cm and non-germination to calculate their composition rates, number of lateral roots, lengths of hypocotyl and root diameters at middle and hook of hypocotyl, and fraction dry weights were measured. Germination and growth responses of the cultivars were changed by AT and AP treatments. The responses, lateral root formation and fresh weights were, however, mainly affected by the cultivars used rather than Af treatment. Rate of the sprouts which formed lateral roots was decreased with increased periods to 4 hours, but their number per sprout was not different between the treatments of longer than 3 hours. Lengths of hypocotyl and root organ and total fresh weights were the highest in an hour AP treatment although longer than 3 hour AP treatments did not showed the significant difference in the lengths. Conclusionally AP treatment was more important than Af one in seed aeration for soybean sprout culture immediately after imbibition into BA solution, and was done at least for 3 hours.

• Korean Journal of Medicinal Crop Science
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• v.21 no.2
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• pp.118-123
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• 2013

This study was carried out to select optimal shade materials among four-layered polyethylene (PE) net (FLPN), aluminium-coated PE sheet (APSS), and blue PE sheet (BPSS) in condition of paddy field cultivated 6-year-old ginseng. The order of light-penetrated ratio and air temperature by shade materials was BPSS > APSS > FLPN. Light-penetrated ratio of BPSS before two fold shade was more 3 times and 2 times than that of FLPN and APSS, respectively. Air temperature of BPSS was also higher $1.6^{\circ}C$ and $1.4^{\circ}C$ than that of FLPN and APSS, respectively. BPSS showed good cultural environment because all of light-penetrated ratio and air temperature were become higher in spring and fall season but lower in summer season by additional shade with two-layered PE net. Survived-leaf ratio was highest in BPSS and lowest in FLPN causing a little water leak on a rainy day. Rusty-root ratio was also highest in FLPN because soil moisture content was increased by water leak. The order of root yield was BPSS > APSS > FLPN, and the cause of highest yield in BPSS was higher light-penetrated ratio during spring and fall season, higher survived-leaf ratio, and lower rusty-root ratio than that of APSS and FLPN. BPSS showed highest total ginsenoside content because of high light-penetrated ratio, blue light effect, and the difference in dry matter partitioning ratio such as low taproot ratio, and high lateral root ratio.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.151-158
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• 1993

Since the inhibition of floral induction was considered to be an important subject to get high yield of Angelica gigas, the effects of low temperature, daylengh and shading were investigated in this study. The yield of A. gigas root grown by inhibition of floral induction was compared with the yield obtained by traditional cultivation method. When the seedings were exposed to the natural low air temperature condition until late of November, the plants which had 6 to 8 leaves showed vernalizing effect, and when the low temperature treatment was prolonged until mid of January, 4 to 5 leaf plants showed vernalizing effect. But 2 to 3 leaf plants did not show vernalizing effect regardless of the length of chilling treatment. The effectiveness of exposure to low temperature was markedly dependent upon the age of plants. In the artificial low temperature treatment the range of temperature varied with plant age. Vernalizing effect at 1,5 and 9$^{\circ}C$ of temperature did not show 3,5,6 leaf plants, respectively. The bolting percent in 8 leaf plant at 1,5 and 9$^{\circ}C$ for 8 weeks decreased by 80,45 and 5%, respectively. As daylength became longer, the bolting percent of A. gigas was increased. plants which were grown in the full sunlight showed the highest value in bolting percent, and the bolting percent was not decreased significantly with changing from full sunlight to 50% shading. When A. gigas were grown by the inhibition of floral induction, dry root weight per l0a showed the greatest value in 3 year old plant which 3.6 and 2.4 times higher than that of 1 and 2 year old plant, respectively. The yield of root was increased by 73.7% in 2 year old plant and 159.6% in 3 year old plant compared with the yield obtained by traditional cultivation method.

• Journal of Ocean Engineering and Technology
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• v.16 no.2
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• pp.72-79
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• 2002

In this study, time-dependent distributions of temperature and stresses, in the box-column welded from ultra thick plates with center segregation, has been analyzed by the commercial finite element package SYSWELD+, for several types and angles of groove. The major points of investigation are the optimum type and angle of groove that minimize weld stress specially at the center segregation, as well as temperature distribution, residual stresses and changes in the mechanical properties. The results can be summarized as follows; 1) Generally the thermal cycle at the root of groove exhibits relatively rapid cooling pattern, however, most of the other part weldment have a slow cooling pattern in all groove types. 2) Most of the micro-structures of weldment are composed of ferrite and pearlite, meanwhile we could find martensite and bainite locally a the root of the groove. 3) Optimum groove type for high heat input welding of box-column corner is a double groove type, and the optimum angle for the groove is 30~$45^{\circ}$ that minimize deformation and weld stress at the center segregation.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.4
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• pp.209-213
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• 1974

The isozymes of glutamic oxalacetic transaminase from young rice root were isolated by DEAE-cellulose column chromatography, and investigated some of their enzymic properties. Obtained results were summarized as follows: 1. 93 percent of GOT activity in rice root existed in supernatant fraction, and their specific activity exibited the same pattern. 2. The rice root contained two types of GOT isozyme; cationic and anionic GOT. It seemed that both of them were distributed in supernatant fraction. 3. GOT isozymes of rice root on the pH dependance showed their maximum activity at 7.4. 4. On the stability of GOT isozymes for temperature, anionic GOT was more unstable than cationic GOT. 5. Apparent Michaelis constant for L-aspartate of GOT isozymes from rice root showed 12-14mM in the cationic GOT and 16mM in the anionic GOT, respectively.