• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.75-80
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• 1998

Disbudded epicotyl cuttings from light-grown 6-day-old seedings of Vigna angularis Owhi et Ohashi were preincubated in $2\;\times\;10^{-4}M$ IAA solution for 48 hr to promote adventitious root formation in upright or inverted direction and then incubated in upright direction for 96 hr. Adventitious root formation occurred only at the morphological base of the cuttings which were preincubated in upright direction, while at the both ends in inverted direction. IAA treatment enhanced the adventitious root formation in all cuttings regardless of their orientation during preincubation. To elucidate localized root development, the activity of enzymes involved in root initiation and development was measured 24 hr, 48 hr, and 148 hr after epicotyl incubation. IAA oxidase, peroxidase and catalase were assayed in the apical, middle and basal segment of the epicotyls, and their fresh weight and length were measured. Elongation occurred the most in the upper segment of the epicotyl while fresh weight gain was the most in the basal segment. At root initiation phase, 24 hr after incubation IAA peroxidase and catalase activities appeared high at rooting zone while IAA oxidase activity was low at both ends, IAA oxidase and peroxidase activities declined at the rooting zone during the adventitious root formation at 48 ht. Inversion of cuttings during preincubation caused a chrange of enzyme activities along their epicotyl cuttings. Only peroxidase activity showed a high correlation with root initiation. Therefore, the biochemical change is highly correlated with change in IAA level in the rooting zone of the epicotyl, resulting in root formation in unusual rooting zone of epicotyl.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.380-386
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• 2001

This study was conducted to investigate the influence of the root zone temperature on the changes in soil physicochemical environment and the growth of the apple trees. Root zone temperatures applied were 20. 25. 30. and $35^{\circ}C$. A pot experiment of 4-year-old fruit-bearing Fuji/M.26 apple trees was done from May 15. 1997 to August 15. 1997. Shoot length and shoot number of 4-year-old Fuji/M.26 was longest at $30^{\circ}C$ but decreased at $35^{\circ}C$. Oxygen concentrations in soil air were maintained from 17 to 18% at $20^{\circ}C$ but fluctuated from 10 to 14% at the end at $35^{\circ}C$. Carbon dioxide concentrations in soil air was highest at $35^{\circ}C$. Organic matter contents in soil decreased as root zone temperature and duration of treatment increased. Nitrate and ammonium contents in soil increased with rising root zone temperature in the beginning but nitrate contents decreased at $35^{\circ}C$ as time progressed. Nitrate content was higher in 10~15cm subsoil than in 25~30cm subsoil.

• Journal of Korean Neurosurgical Society
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• v.52 no.4
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• pp.384-390
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• 2012

Objective : The objective of this study was to investigate the morphologic characteristics between the vertebral body and the regions of the cervical and thoracic spinal cords where each rootlets branch out. Methods : Sixteen adult cadavers (12 males and 4 females) with a mean age of 57.9 (range of 33 to 70 years old) were used in this study. The anatomical relationship between the exit points of the nerve roots from the posterior root entry zone at each spinal cord segment and their corresponding relevant vertebral bodies were also analyzed. Results : Vertical span of the posterior root entry zone between the upper and lower rootlet originating from each spinal segment ranged from 10-12 mm. The lengths of the rootlets from their point of origin at the spinal cord to their entrance into the intervertebral foramen were 5.9 mm at the third cervical nerve root and increased to 14.5 mm at the eighth cervical nerve root. At the lower segments of the nerve roots (T3 to T12), the posterior root entry zone of the relevant nerve roots had a corresponding anatomical relationship with the vertebral body that is two segments above. The posterior root entry zones of the sixth (94%) and seventh (81%) cervical nerve roots were located at a vertebral body a segment above from relevant segment. Conclusion : Through these investigations, a more accurate diagnosis, the establishment of a better therapeutic plan, and a decrease in surgical complications can be expected when pathologic lesions occur in the spinal cord or vertebral body.

• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.60-69
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• 2016

In this study, we estimated root zone soil moisture dynamics using remotely sensed (RS) data. A soil moisture data assimilation scheme was used to derive the soil and root parameters from MODerate resolution Imaging Spectroradiometer (MODIS) data. Based on the estimated soil/root parameters and weather forcings, soil moisture dynamics were simulated at spatio-temporal scales based on a hydrological model. For calibration/validation, the Little Washita (LW13) in Oklahoma and Chungmi-cheon/Seolma-cheon sites were selected. The derived water retention curves matched the observations at LW 13. Also, the simulated soil moisture dynamics at these sites was in agreement with the Time Domain Reflectrometry (TDR)-based measurements. To test the applicability of this approach at ungauged regions, the soil/root parameters at the pixel where the Seolma-cheon site is located were derived from the calibrated MODIS-based (Chungmi-cheon) soil moisture data. Then, the simulated soil moisture was validated using the measurements at the Seolma-cheon site. The results were slightly overestimated compared to the measurements, but these findings support the applicability of this proposed approach in ungauged regions with predictable uncertainties. These findings showed the potential of this approach in Korea. Thus, this proposed approach can be used to assess root zone soil moisture dynamics at spatio-temporal scales across Korea, which comprises mountainous regions with dense forest.

• 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.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.454-461
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• 1999

The dynamics of root system in the fairy rings of Tricholoma matsutake was investigated in four zones divided into 'zone of decayed mycorrhizae', 'zone of mycorrhizae for fruiting', 'zone of physiologically active mycorrhizae' and 'zone of roots free from mycorrhizal infection'. The roots of Pinus densiflora in fairy rings, which occupied 70% of upper crown, comprised about 60% and 87% of total roots and alive roots, respectively. The ratio of fine-roots of P. densiflora over total roots was relatively higher than other species since that of P. densiflora was about 45% while that of the other species was about 13% on research of fine-roots. Especially, the roots of pine comprised about 70% of total root in the zone of mycorrhizae for fruiting and the zone of physiologically active mycorrhizae, which indicated that the pine roots were closely related to the fairy rings of T. matsutake. The fine roots of P. densiflora in the zone of physiologically active mycorrhizae was about 60.7%(1,087mg/100g soil) which was about twice compared to that of other zones. It allowed us to suppose that the fine roots of P. densiflora can make active growth in the zone of physiologically active mycorrhizae, and the growth was promoted by the fairy ring formation of T. matsutake. In addition, we found 3~5 times higher amount of fine roots than that of medium roots of P. densiflora in this zone, which indicated that the fairy rings of T. matsutake locate in the region of active growth of P. densiflora' roots.

• Molecules and Cells
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• v.23 no.1
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• pp.115-121
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• 2007

Root nodule formation is controlled by plant hormones such as auxin. Auxin-repressed protein (ARP) genes have been identified in various plant species but their functions are not clear. We have isolated a full-length cDNA clone (EuNOD-ARP1) showing high sequence homology to previously identified ARP genes from root nodules of Elaeagnus umbellata. Genomic Southern hybridization showed that there are at least four ARP-related genes in the genome of E. umbellata. The cDNA clone encodes a polypeptide of 120 amino acid residues with no signal peptide or organelle-targeting signals, indicating that it is a cytosolic protein. Its cytosolic location was confirmed using Arabidopsis protoplasts expressing a EuNOD-ARP1:smGFP fusion protein. Northern hybridization showed that EuNOD-ARP1 expression was higher in root nodules than in leaves or uninoculated roots. Unlike the ARP genes of strawberry and black locust, which are negatively regulated by exogenous auxin, EuNOD-ARP1 expression is induced by auxin in leaf tissue of E. umbellata. In situ hybridization revealed that EuNOD-ARP1 is mainly expressed in the fixation zone of root nodules.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.46-54
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• 2019

Experiments of local cooling and heating on crown and root zone of forcing cultivation of strawberry 'Seolhyang' using heat pump and root pruning before planting were conducted. During the daytime, the crown surface temperature of the crown local cooling treatment was maintained at $18{\sim}22^{\circ}C$. This is suitable for flower differentiation, while those of control and root zone local cooling treatment were above $30^{\circ}C$. Budding rate of first flower clusters and initial yields were in the order of crown local cooling, root zone local cooling and control in root pruning plantlet and non pruning plantlet, except for purchase plantlet. Those of root pruning plantlet were higher than those of non pruning plantlet. These trends were evident in the yield of the first flower cluster until February 14, 2018, and the effect of local cooling and root pruning decreased from March 9, 2018. The budding rates of the second flower cluster according to the local cooling and root pruning treatments were not noticeable compared to first flower cluster but showed the same tendency as that of first flower cluster. In the heating experiment, root zone local heating(root zone $20^{\circ}C$+inside greenhouse $5^{\circ}C$) and crown local heating(crown $20^{\circ}C$+inside greenhouse $5^{\circ}C$) saved 59% and 65% of heating fuel, respectively, compared to control(inside greenhouse $9^{\circ}C$). Considering the electric power consumption according to the heat pump operation, the heating costs were reduced by 55% and 61%, respectively.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.115-124
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• 1999

This study was conducted to determine the optimum root zone environment condition and proper nutrient management system for lettuce in hydroponics. For the root zone environment condition, several level of pH and electrical conductivity (EC) were treated respectively. Though all the level of pH 4 to pH 8, except pH 3, performed better growth without any visible physiological disorder, the optimum pH of the nutrient solution for lettuce production was pH 5.5 to 6.0. The optimum ionic strength of the solution was EC 1.2 to 1.6 mS $cm^{-1}$ / because higher nutrient level caused tip burn symptom by calcium deficiency. Considering the above results, it is concluded that lettuce can be efficiently mass-produced through the optimum root zone environment.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.36-41
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• 1999

This study was carried out to investigate the effect of root zone restriction on yield and quality of muskmelon. Three cultivation methods, isolated bench, root zone restriction sheet(RZR sheet) and conventional soil culture, were compared from April 19th to July 17th. Soil temperature was higher at isolated bench and the growth of melon was accelerated at isolated bench compared to soil culture or RZR sheet. Fruit size was bigger in order of soil culture, isolated bench and RZR sheet, while sugar content and net shape were greatest at isolated bench, and the percentage of wilted plant was 3.3% at isolated bench, 25.0% at RZR sheet and 26.7% at soil culture. Therefore, marketable yield was higher at isolated bench compared to conventional soil culture.