• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.62 no.1
• /
• pp.1-8
• /
• 2017

We investigated the effect of silicate coating of rice seeds on bakanae disease incidence and the quality of seedlings raised in seedling boxes and transplanted into pots. The silicate-coated rice seed (SCS) was prepared as follows. Naturally infested rice seeds not previously subjected to any fungicidal treatment were dressed with a mixture of 25% silicic acid at pH 11 and 300-mesh zeolite powder at a ratio of 50 g dry seed - 9 mL silicic acid - 25 g zeolite powder. The following nursery conditions were provided : Early sowing, dense seeding in a glass house with mulching overnight and no artificial heating, which were the ideal conditions for determining the effect on the seed. The nursery plants were evaluated for Gibberella. fujikuroi infection or to determine the recovery to normal growth of infected nursery plants in the Wagner pot. Seedlings emerged 2-3 days earlier for the SCS than they did for the non-SCS control, while damping-off and bakanae disease incidence were remarkably reduced. Specifically, bakanae disease incidence in the SCS was limited to only 7.8% for 80 days after sowing, as compared to 91.6% of the non-SCS control. For the 45-days-old SCS nursery seedlings, the fresh weight was increased by 11% and was two times heavier, with only mild damage compared to that observed for non-SCS. Even after transplanting, SCS treatment contributed to a lower incidence of further infections and possibly to recovery of the seedlings to normal growth as compared to that observed in symptomatic plants in the pot. The active pathogenic macro-conidia and micro-conidia were considerably lower in the soil, root, and seedling sheath base of the SCS. In particular, the underdeveloped macro-conidia with straight oblong shape without intact septum were isolated in the SCS ; this phenotype is likely to be at a comparative etiological disadvantage when compared to that of typical active macro-conidia, which are slightly sickle-shaped with 3-7 intact septa. A active intact conidia with high inoculum potential were rarely observed in the tissue of the seedlings treated only in the SCS. We propose that promising result was likely achieved via inhibition of the development of intact pathogenic conidia, in concert with the aerobic, acidic conditions induced by the physiochemical characteristics associated with the air porosity of zeolite, alkalinity of silicate and the seed husk as a carbon source. In addition, the resistance of the healthy plants to pathogenic conidia was also important factor.

• The Journal of Korean Academy of Prosthodontics
• /
• v.53 no.3
• /
• pp.207-214
• /
• 2015

Due to the limitations of conventional removable partial denture prostheses to treat a cleft lip & palate patient who shows scar tissue on upper lip, excessive absorption of the maxillary residual alveolar ridge, and class III malocclusion with narrow palate and undergrowth of the maxilla, 4 implants were placed on the maxillary edentulous region and a maxillary removable implant-supported partial denture was planned using a CAD/CAM milled titanium bar. Unlike metal or gold casting technique which has shrinkage after the molding, CAD/CAM milled titanium bar is highly-precise, economical and lightweight. In practice, however, it is very hard to obtain accurate friction-fit from the milled bar and reduction in retention can occur due to repetitive insertion and removal of the denture. Various auxiliary retention systems (e.g. $ERA^{(R)}$, $CEKA^{(R)}$, magnetics, $Locator^{(R)}$ attachment), in order to deal with these problems, can be used to obtain additional retention, cost-effectiveness and ease of replacement. Out of diverse auxiliary attachments, $Locator^{(R)}$ has characteristics that are dual retentive, minimal in vertical height and convenient of attachment replacement. Drill and tapping method is simple and the replacement of the metal female part of $Locator^{(R)}$ attachment is convenient. In this case, the $Locator^{(R)}$ attachment is connected to the milled titanium bar fabricated by CAD/CAM, using the drill and tapping technique. Afterward, screw holes were formed and 3 $Locator^{(R)}$ attachments were secured with 20 Ncm holding force for additional retention. Following this procedure, satisfactory results were obtained in terms of aesthetic facial form, masticatory function and denture retention, and I hereby report this case.

• Journal of Bio-Environment Control
• /
• v.19 no.1
• /
• pp.31-35
• /
• 2010

In this experiment, the effects on the growth and the quality of cut flowers of chrysanthemum 'Jinba' were mainly concerned depending on cultural methods between the pinching and the non-pinching. According to the results, the sufficient period of the vegetative growth was necessary to enter the flower bud differentiation in case of the non-pinching cultivation whereas it was not the case on the pinching. As compared with the pinching, the non-pinching showed 10% higher in the flowering ratio after flower bud differentiation. The flowering ratio of the non-pinching exceeded more than 95% but the pinching showed below 95% of the flowering ratio after flower bud differentiation. Comparing the number of cutting flowers between pinching and non-pinching, it was the non-pinching that showed the production of the first grade cutting flowers about 5 weeks faster than that of the pinching. It seem to be possible that harvesting time and growing period could be shortened. In the non-pinching growing region, above third-grading marketable cut flowers was 100% regardless of planting time. On the contrary, the pinching method showed 84.7% of marketable cutting flowers at first week from the planting, followed by 64.3% at second week, 18.8% at third week, and 2.6% at fourth week. Marketability of cutting flowers indicates that were planted by the pinching is very poor. When draw a comparison between the fourth-week planting of the non-pinching with the first-week planting of the pinching, the non-pinching could cut the growing period 38 days shorter than the pinching and the marketability was better. These results indicate that the non-pinching method can shorten the growing period and harvesting time compared to the pinching and it also resulted in reduction of cost and rapid production of the cutting flowers.

• Journal of Bio-Environment Control
• /
• v.16 no.4
• /
• pp.328-332
• /
• 2007

This study was conducted to investigate the effects of high concentrations of salts in soil on the growth, yield, quality, photosynthetic rate, and mineral uptake of tomato ('House Momotaro') in pot cultivation. The growth of tomato such as plant height, top plant weight and root weight decreased as the concentrations of salts in soils increased. Yield decreased by 31% and 41% in EC 5.0 and $7.5dS{\cdot}m^{-1}$, respectively compared with the salt concentration of EC $1.5dS{\cdot}m^{-1}$. Yield reduction was caused by low mean weight and number of fruit if at high salt concentration in soil, and affected by low photosynthetic rate and water potential in leaf, The rate of blossom-end rot was highest (16.7%) in EC $7.5dS{\cdot}m^{-1}$ and increased as the concentrations of salts in soils increased. The contents of soluble solids and titratable acids showed a tendency to increase with increasing the concentrations of salts in soils. Photosynthetic rate, water potential and stomatal conductance in leaf decreased as the salt concentration in soil increased. The higher the salt concentration in soil, the lower the mineral uptake such as T-N, P, K, Ca and Mg but, the higher the content of Na.

• Journal of Bio-Environment Control
• /
• v.16 no.4
• /
• pp.314-321
• /
• 2007

This study was conducted to select leaf vegetables suitable for cultivation in apartment verandas and simple and easy fertigation method for home gardening. In order to develop the convenient fertigation method, hydroponics, wick irrigation, and overhead irrigation methods were compared. For the wick irrigation, two types of nutrient sources were used; one was slow release fertilizers mixed with medium and the other one was nutrient solution filled in container located under pots. The growth of leafy lettuce, leaf mustard, and leaf beet was better in both of the wick irrigation methods rather than in overhead irrigation and hydroponics. The wick irrigation method is very easy, so that it is expected to bring a good result from the cultivating and managing point of view, if it brings with commercialized system along with slow release fertilizer. As a result of investigation of environment such as temperature, relative humidity, and irradiance level in apartment verandas in autumn the highest irradiance level during a day was just 48% and 35% in verandas facing south and feeing southeast, respectively, comparing to that in greenhouse. The light environment was investigated as a limiting factor for vegetable growing in verandas. Therefore, to select the vegetables showing good growth under low irradiance environment, nine leaf vegetables such as romaine lettuce, lent lettuce, head lettuce, endive, pak-choi, leaf mustard, garland chrysanthemum, leaf beet, and Chinese chive were grown under 0%, 50%, 70%, 90% shading. Among them, Chinese chive showed the best growth under low irradiance levels. Endive showed line growth reduction according to shading degree, however, even under 90% shading condition, it showed good growth. And then leafy lettuce, garland chrysanthemum, and pak-choi followed. Therefore, these results will be of help in selecting vegetables for veranda gardening with different light levels.

• Journal of Bio-Environment Control
• /
• v.19 no.4
• /
• pp.360-365
• /
• 2010

The effects of precooling treatments on the storability of chicon were investigated during modified atmosphere (MA) storage. The forced air cooling showed faster precooling rate that reduced the internal temperature of chicon to $2{\pm}1^{\circ}C$, and the precooling time of forced air cooling was 1/6 of room cooling. The half cooling time was 3 hr 21 min in room cooling and 1 hr 17 min in forced air cooling. Weight loss was less than 0.5% in all treatments both $5^{\circ}C$ and $10^{\circ}C$ MA storage and maintained higher in forced air cooling treatment. The concentration of carbon dioxide, oxygen, and ethylene of $50{\mu}m$ ceramic film packages were observed higher at $10^{\circ}C$ than $5^{\circ}C$. The precooling effect on respiration reduction was not shown at $5^{\circ}C$, but appeared that the gas concentration of precooling treatments showed less carbon dioxide and higher oxygen than non precooling treatment by 9 days after $10^{\circ}C$ storage. Ethylene concentration of precooling treatments showed lower than non precooling treatment until 3 days both $5^{\circ}C$ and $10^{\circ}C$ MA storage. Precooling showed the effect on maintaining visual quality of chicon both $5^{\circ}C$ and $10^{\circ}C$ MA storage. However, the forced air cooling that showed faster precooling rate did not appeared more precooling effect on the visual quality than room cooling because the fast air flow (6.0 m/sec) of forced air cooling hit directly on chicon outer leaves and might cause physical damage to chicon. Although the forced air cooling showed the effect on maintaining quality of chicon, but additional studies should be needed that investigated proper air flow rate and cooling box structure can prevent physical damage by air flow.

• Journal of Bio-Environment Control
• /
• v.17 no.2
• /
• pp.90-95
• /
• 2008

It has become a big matter of concerns that the skill and measures against reduction of energy and cost for heating a protected horticultural greenhouse were prepared. But in these days necessity of cooling a protected horticultural greenhouse is on the rise from partial high value added farm products. In this study, therefore, a horizontal type geothermal heat pump system with 10 RT scale to heat and cool a protected horticultural greenhouse and be considered to be cheaper than a vertical type geothermal heat pump system was installed in greenhouse with area of $240\;m^2$. And cooling performances of this system were analysed. As condenser outlet temperature of heat transfer medium fluid rose from $40^{\circ}C$ to $58^{\circ}C$, power consumption of the heat pump was an upturn from 11.5 kW to 15 kW and high pressure rose from 1,617 kPa to 2,450 kPa. Cooling COP had the trend that the higher the ground temperature at 1.75 m went, the lower the COP went. The COP was 2.7 at ground temperature at 1.75 m depth of $25.5^{\circ}C$ and 2.0 at the temperature of $33.5^{\circ}C$ and the heat extraction rate from the greenhouse were 28.8 kW, 26.5 kW respectively at the same ground temperature range. 8 hours after the heat pump was operated, the temperature of ground at 60 cm and 150 cm depth buried a geothermal heat exchanger rose $14.3^{\circ}C$, $15.3^{\circ}C$ respectively, but the temperature of ground at the same depth not buried rose $2.4^{\circ}C$, $4.3^{\circ}C$ respectively. The temperature of heat transfer medium fluid fell $7.5^{\circ}C$ after the fluid passed through geothermal heat exchanger and the fluid rejected average 46 kW to the 1.5 m depth ground. It analyzed the geothermal heat exchanger rejected average 36.8 W/m of the geothermal heat exchanger. Fan coil units in the greenhouse extracted average 28.2 kW from the greenhouse air and the temperature of heat transfer medium fluid rose $4.2^{\circ}C$after the fluid passing through fan coil units. It was analyzed the accumulation energy of thermal storage thank was 321 MJ in 3 hours and the rejection energy of the tank was 313 MJ in 4 hours.

• Journal of Bio-Environment Control
• /
• v.25 no.4
• /
• pp.249-254
• /
• 2016

This study was carried out to evaluate the efficiency of white shading agent for reduction of greenhouse air temperature and to develop cost-effective cooling strategies for strawberry seedling production during hot seasons. Experiment results showed that solar radiation ($W/m^2$) was reduced by 14~17% and 33~37% for 15% and 35% white wash shading treatments, respectively, in black shading net treatment solar radiation was reduced by 39~44% compared to non-shaded treatment. Measured greenhouse air temperatures in 15% and 35% white wash shading treatments were $38.4^{\circ}C$ and $36.5^{\circ}C$, respectively, whereas in black shading net covered greenhouses air temperature was $35.1^{\circ}C$, thereby 35% and 15% shading treatments showed 3.3 and $1.9^{\circ}C$ higher air temperatures than black net shading treatment. Crown diameter of strawberry plants in black net shading treatment was 7.5mm, and in 15% and 35% white wash shading treatments were 8.6mm and 8.3mm, respectively. Strawberry transplants grown in 35% white wash shading treatment produced the highest above ground fresh weight(7.8g), followed by 15% white wash shading(6.7g) and black net shading treatments(5.8g). Also, both 15% and 35% white wash shading treatments produced higher root fresh weight(4.1g and 4.3g) compare to black net shading treatments(2.7g).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.3
• /
• pp.341-348
• /
• 2014

We investigated the anti-obesity and anti-hyperlipidemic effects of extracts of two roasted coffee beans (Vietnam robusta and Ethiopia mocha sidamo G2) and fermented coffee beans with Monascus rubber mycelium (MR) by solid-state culture. C57B/L6 mice were divided into seven groups: normal diet (ND) group, high fat diet (HFD) group, and HFD groups with hot water extracts from Vietnam robusta coffee beans (HFD-VR), MR-fermented Vietnam robusta coffee beans (HFD-VR-MR), MR-fermented Vietnam robusta coffee beans with 10% brown rice (HFD-VR-MR-BR10), Ethiopia mocha sidamo G2 coffee beans (HFD-ES), and MR-fermented Ethiopia mocha sidamo G2 coffee beans (HFD-ES-MR). After 6 weeks, body weight gain and food efficiency ratio were higher in the HFD group, but significantly reduced in the coffee extracts-fed groups. The HFD-ES-MR group showed greater body weight reduction than the HFD-ES group. The serum triglyceride, total cholesterol, and LDL-cholesterol levels as well as the atherogenic index and cardiac risk factor all tended to decrease in groups fed Vietnam robusta coffee extracts compared to the HFD group. These results suggest that Vietnam robusta and Ethiopia mocha sidamo G2 may be used to make functional coffee beverages with anti-obesity and anti-hyperlipidemic activities.

• Journal of Bio-Environment Control
• /
• v.7 no.1
• /
• pp.43-54
• /
• 1998

This experiment was conducted to develop optimal nutrient solution for tomato plants, according to the plant growth stages in closed system. Perlite substrate was supplied with 1/2 and 1 strength of the solution of National Horticultural Research Station in Japan. Plants grew better and the nutrient_contents in the leaves were also proper in 1 strength. Based on these results, optimal nutrient solution in perlite was composed by n/w of 1 strength according to the plant growth rates ： N 13.5, P 3.3, K 7.0, Ca 7.0, Mg 3.5 me.L$^{-1}$ in seedling stage, N 14.2, P 3.3, K 8.0, Ca 7.5, Mg 4.0 me.L$^{-1}$ in vegetative stage and N 10.0, P 3.0, K 7.0, Ca 6.0, Mg 3.0 me.L$^{-1}$ in reproductive stage. To examine the suitability of the nutrient solution developed in this experiment, tomato plants were grown in rockwool and supplied with two different composition and concentration of nutrient solution composed by n/w of 1 strength in perlite (SCUT) and by Research Station for Greenhouse Vegetable and Floriculture on the Netherlands (PBG). PH and EC in SCUT were changed little in 1 strength but a significant change of PH was shown in 1/2 strength. Later, drained solutions in rockwool were also analyzed according to the Plant growth stages. Low concentrations of N and P in root zone were shown in early growth stage but N was increased in reproductive stage, while, K, Ca, Mg concentration was consistent through the whole growth stage. Considering these results, we found that the rebalance of N and P was needed, that is, reduction of N concentration in reproductive stage and increasing of P concentration in vegetative stage.