• Journal of Ginseng Research
• /
• v.3 no.2
• /
• pp.105-112
• /
• 1979

Effect of gibberllin on the breaking of bud dormancy of root and growth of aerial parts were investigated under laboratory and field condition for the prolongation of shoot growth duration, shortening of fruit bearing age and the increase of root yield. Drop application of GA (0.5ml of 50ppm) on rhizome of one year old root broke bud dormancy better than by low temperature. Soaking for one hour of one year old roots which wintered in the field in GA (50-200ppm) greatly accelerated the emergence of new buds while kinetin was only effective at low level (50ppm). GA substantially increased stem length in early stage and petiole length later on while kinetin increased stem diameter. Under the field condition with polythylene film tunnel (PET) in early spring the soaking in GA (50ppm for 1 hour) of rhizome of 4 year old root with replanting and dropping GA (50ppm, 1ml) on rhizome without replanting brought earlier emergence (29days) in comparison with that in the usual field. PET alone caused 14 day-early emergence. GA increased the length of stem and petiole only in early stage and replanting decreased only petiole length in later stage. Soaking in GA with replanting caused the Pronounced decrease in peduncle length, percentage of (ruin set and dry weight of reproductive organ (fruits and peduncle). Dropping without replanting showed significant decrease only in dry weight of reproductive organ. Fruit maturing was 20 days earlier than in usual held with little difference between GA and PET. It is well expected that GA could be used for early emergence of bud, shortening of root dormancy period, thinning of fruit and higher root yield according to application amount and methods.

• The Plant Pathology Journal
• /
• v.29 no.4
• /
• pp.440-445
• /
• 2013

Balloon flower (Platycodon grandiflorum) is a kind of mountain herbs whose roots have restorative properties and the cultivating acreage of balloon flower has been steadily increasing in Korea. More frequent rain and high amount of rainfalls as a result of climate changes predisposed balloon flower to the outbreaks of root rot at high-density cultivation area in recent years. Root crowns were usually discolored into brown to blackish brown at first and the infected plants showed slight wilting symptom at early infection stage. Severely infected roots were entirely rotted and whole plants eventually died at late infection stage. The overall disease severities of root rot of balloon flower were quite variable according to the surveyed fields in Jeonnam, Gyeongnam and Jeju Provinces, which ranged from 0.1% to 40%. The root rot occurred more severely at the paddy or clay soils than the sandy soils and their severities were much higher at lowland than upland in the same localty. The disease increased with aging of the balloon flower. The causal fungi were identified as Fusarium solani and F. oxysporum on the basis of their mycological characteristics. The optimum temperature ranges of their mycelial growths was found to be $24^{\circ}C$. The pathogenic characters of F. solani and F. oxysporum treated by artificial wounding inoculation on healthy roots of balloon flower revealed that F. solani was more virulent than F. oxysporum. This study identified the causal agents of root rot of balloon flower as Fusarium solani and F. oxysporum, probably for the first time.

• The Korean Journal of Community Living Science
• /
• v.26 no.3
• /
• pp.489-498
• /
• 2015

This study investigates the effects of a China root (Smilax china L.) extract on the chemical and microbiological characteristics and antioxidant activity of the sausage stew sauce and the soft-tofu stew sauce over a 5-week storage period. Commercial sauces were obtained from the market, and samples were prepared using four different concentrations of the China root extract (0% (control), 0.5%, 1.0%, and 1.5%) and stored at $5^{\circ}C$ and $20^{\circ}C$. Over the 5-week storage period, pH and salinity showed slight changes in both the sausage and soft-tofu stew sauces, but there was no significant difference (p<0.05) regardless of the extract amount and temperature. At 5 weeks, there were significant decreases in the total microbial count in groups with the China root extract (p<0.05) for both the sausage and soft-tofu stew sauces at $5^{\circ}C$. Over the whole storage period, no coliform, yeast, and mold were detected in any sample. S. aureus counts were not detected in 1.0% and 1.5% China root groups at $5^{\circ}C$, but 1.00-1.60 log CFU/g was found in the control and 0.5% groups. DPPH radical scavenging activity at 5 weeks showed an increase with an increase in the amount of the China root extract in both sauces. These results indicate that the China root extract inhibited microbial growth during storage as well as scavenging activity and thus that it can be considered to prolong the shelf life of commercial sauces.

• Restorative Dentistry and Endodontics
• /
• v.42 no.1
• /
• pp.27-33
• /
• 2017

Objectives: To determine the optimal timing for post space preparation of root canals sealed with epoxy resin-based AH Plus sealer in terms of its polymerization and influence on apical leakage. Materials and Methods: The epoxy polymerization of AH Plus (Dentsply DeTrey) as a function of time after mixing (8, 24, and 72 hours, and 1 week) was evaluated using Fourier transform infrared (FTIR) spectroscopy and microhardness measurements. The change in the glass transition temperature ($T_g$) of the material with time was also investigated using differential scanning calorimetry (DSC). Fifty extracted human single-rooted premolars were filled with gutta-percha and AH Plus, and randomly separated into five groups (n = 10) based on post space preparation timing (immediately after root canal obturation and 8, 24, and 72 hours, and 1 week after root canal obturation). The extent of apical leakage (mm) of the five groups was compared using a dye leakage test. Each dataset was statistically analyzed by one-way analysis of variance and Tukey's post hoc test (${\alpha}=0.05$). Results: Continuous epoxy polymerization of the material with time was observed. Although the $T_g$ values of the material gradually increased with time, the specimens presented no clear $T_g$ value at 1 week after mixing. When the post space was prepared 1 week after root canal obturation, the leakage was significantly higher than in the other groups (p < 0.05), among which there was no significant difference in leakage. Conclusions: Poor apical seal was detected when post space preparation was delayed until 1 week after root canal obturation.

• Journal of Ginseng Research
• /
• v.6 no.1
• /
• pp.75-83
• /
• 1982

In this study it was found that the enzyme activities of diseased ginseng contributed greatly on the development of its root-rot disease. The 4i sensed ginseng showed higher activities of $\alpha$-amylase, p amylase, invertase, catalase, and cellulase than those of fresh one. The increased enzyme activities of diseased ginseng were originated in those from infected pathogens, which showed a proportional relationship between enzyme activities and root-rot power of them. The increases of enzyme activities during incubation of inoculated ginseng could be considerably depressed by controlling culture environments as to temperature below 4$^{\circ}C$, pH 8-9, and relative humidity about 60%, Some metal ions and organic reagents also inhibited the enzyme activities of diseased ginseng. But their inhibitory effects were not so great that they might be used to protect the disease.

• Korean Journal of Medicinal Crop Science
• /
• v.3 no.2
• /
• pp.77-80
• /
• 1995

This study was carried out to know the effect of air temperature on photosynthesis and growth of Korean Valerian (valeriana fauriei var. dasycarpa HARA). The results are as follows; 1. Photosynthesis of V fauriei had highly significant relation to temperature in a quadratic regression mo­del, from which the optimum temperature for the plant growth were estimated to be $17.7^{\circ}C$. During the day­time in the field condition, the photosynthesis rate was highest at 9 a.m, then reduced to minimum at 2 p.m., and increased again thereafter. 2. Number of stomata was about $25/mm^2$ on the upper side and $85/mm^2$ on the lower side of the leaf, and the size was $21{\sim}30/{\mu}m$ in diameter. 3. 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 $20.3^{\circ}C$.

• The Korean Journal of Ecology
• /
• v.18 no.3
• /
• pp.323-332
• /
• 1995

Effects of wintering and temperature on nitrogen fixation activity of nodules of Melilotus suaveolens Ledeb. grown in the field and growth chamber conditions were investigated. The biennial plants transfered to the growth chamber from winter field recovered the activity in 3 weeks of incubation and attained the maximum rate of $153{\mu}mol\;C_2H_4{\cdot}g$ fr wt $nodule^{-1}{\cdot}h^{-1}$ in 5 weeks. When root nodules which adapted to different temperatures, were pretreated with 10, 20 and $30^{\circ}C$ for 1 hour, and then transfered to $30^{\circ}C$, nitrogen fixation activity was promoted in the nodules exposed to lower field temperature ($12^{\circ}C$) with 1$0^{\circ}C$ pretreatment. M. suaveolens maintained nitrogen fixation activity in the wide range of temperatures, and was more tolerant to lower temperature than those of other woody leguminous plants, Diurnal changes of nodule activity showed increase with sunrise and decrease with sunset during spring and autumn, but the activity was inhibited during July and August because of high temperature with stron irradiation. Nitrogen fixation activity of annual plant appeared in mid-April, and showed two peaks (104 and 43 mol $C_2H_4{\cdot}g$ fr wt $nodule^{-1}{\cdot}h^{-1}$) in July and September, and then disappeared after October. Nitrogen fixation activity of biennial plant reappeared in mid-March after wintering and attained two peaks (102 and 82 ${\mu}mol\;C_2H_4{\cdot}g$ fr wt $nodule^{-1}{\cdot}h^{-1}$) in April and June of flowering period, and then disappeared after July due to plant withering by severe drought.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.6
• /
• pp.459-464
• /
• 2002

This experiment was conducted to know the changes of bioactive component content in four-year-old peony (Paeonia lactiflora Pall.) root with various drying methods such as room temperature drying, $50^{\circ}C$ heat-air drying, room temperature drying after $80^{\circ}C$ boiling water treatment and freeze drying, and to establish the optimum drying method for high quality production of Paeoniae Radix. For this purpose, the contents of paeoniflorin, albiflorin and five phenolic compounds (gallic acid, benzoic acid, (+)-catechin, (-)-epicatechin and (+)-taxifolin 3-O-$\beta$-D-glucopyranoside) in peony root with different drying methods were analyzed by RP-HPLC. The contents of paeoniflorin, albiflorin and (+)-taxifolin 3-O-$\beta$-D-glucopyranoside at room temperature drying were higher than in the other drying methods and that of gallic acid at 8$0^{\circ}C$ boiling water treatment was the highest among that of all drying methods. In the case of freeze drying, the contents of (+)-catechin, benzoic acid and (-)-epicatechin were the highest among those of all drying methods. As increase of drying and treatment temperature, the contents of paeoniflorin, albiflorin, (+)-taxifolin 3-O-$\beta$-D-glucopyrano-side, (+)-catechin and benzoic acid were decreased.

• Korean Journal of Food Science and Technology
• /
• v.13 no.2
• /
• pp.133-141
• /
• 1981

The gelatinization phenomena of bracken root starch were examined by means of the loss of birefringence, degree of digestibility by amylase and X-ray diffraction. These results indicated that gelatinization temperature of the starch was $55{\sim}60^{\circ}$ and over 95% of starch were gelatinized at the temperature between 60 and $70^{\circ}C$. The swelling power of the bracken root starch was much less steeper than that of potato or tapioca starch. Amylograph data on the various starch concentrations showed the pasting temperature of $62{\sim}68^{\circ}$, peak height of $80{\sim}840$ Brabender unit (BU) and peak after cooling to $50^{\circ}C$ of $110{\sim}555\;BU.$. According to the information obtained from amylograph data, the bracken root starch showed low set back. The rate of retrogradation of the starch as tested by Texturometer was slower and faster than that of potato and tapioca starches, respectively.

• Horticultural Science & Technology
• /
• v.29 no.2
• /
• pp.102-109
• /
• 2011

This research was conducted to establish efficient methods to control root-zone temperature of tomato plant when cultivated in perlite bag during the summer season. Tomato plants were grown with four selected treatments; covering irrigation pipe by aluminum insulation material (Insulate), discarding nutrient solution inside the irrigation line before each irrigation (Discard), skipping irrigation for two hours from 13:00 to 15:00 (Skip), or no treatment as a control (Non). Based on the analysis of plant development index, all plants with selected treatments grew more vigorous and vegetative in similar growth patterns. The discard treatment exhibited the best root-zone temperature control among the treatments. The discard treatment also resulted in the best root growth and above-ground growth, followed by skip, Insulate and Non. The total yields were obtained by the order of Insulate, Discard, Non and Skip. However the marketable yield was obtained by the order of Discard, Insulate, Skip and Non. The net incomes treated with Discard and Insulate were 9,687,600 and 9,396,000 Korean won per hectare, respectively, exhibiting higher incomes than that of Non. Therefore, it was concluded that insulation of the irrigation pipe and discarding nutrient solution inside the pipe before each irrigation were the most desirable and economical methods in terms of costs and yields.