• Horticultural Science & Technology
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• v.29 no.3
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• pp.187-194
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• 2011

The objective of this study was to determine the effects of light intensity and electrical conductivity (EC) of nutrient solution on the growth and nutrient uptake of potted kalanchoe plants (Kalanchoe blossfeldiana 'Marlene') with growth stage in ebb and flow subirrigation systems. The plants were grown at four ECs of 0.5, 1.0, 1.5, and 2.0 $dS{\cdot}m^{-1}$ for seedling stage and four ECs of 1.0, 1.5, 2.0, and 3.0 $dS{\cdot}m^{-1}$ for short day stage under three daily photosynthetic photon flux (PPF) of 6.5, 10.3, 18.2 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. At seedling stage, plant height was the longest under the lowest light intensity, and particularly dry weights and leaf areas were the highest at PPF 10.3 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. Dry weights and leaf areas were the highest at EC 1.5 $dS{\cdot}m^{-1}$ regardless of light intensity. At short day exposure, plant height was the longest under the lowest light intensity. Dry weights, leaf areas, and number of pedicels of the plants significantly increased as light intensity increased. Under all light intensity conditions, dry weights, leaf areas, and number of pedicles increased until EC becomes to 1.0 - 2.0 $dS{\cdot}m^{-1}$. And after reached the highest at EC 2.0 $dS{\cdot}m^{-1}$, they decreased at EC 3.0 $dS{\cdot}m^{-1}$. By comparing the ion uptakes at EC 1.5 $dS{\cdot}m^{-1}$ of seedling stage and EC 2.0 $dS{\cdot}m^{-1}$ of short day stage in which the plants grew better, we confirmed that ion balance of nutrient solution among $NO_3{^-}$-N, $H_2PO_4{^-}$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were significantly changed at short day stage compared to seedling stage. For better growth of the plants, both ion balance and EC of nutrient solution should be considered under different light intensities at short day stage while control of EC is enough at seedling stage.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.87-94
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• 2011

This study was carried out to investigate the effects of hot solution soaking and chilling treatment on sprouting and enlargement of bulblets obtained through in vitro culture in Korean native lilies with ornamental values. In vitro bulblets of Lilium cernuum, L. hansonii, L. hansonii for. mutatum, L. leichtlinii, and L. tsingtauense were soaked in distilled water or 100 $mg{\cdot}L^{-1}$ $GA_3$ and $GA_{4+7}$ solution maintained at $35^{\circ}C$ for two hours (hot water treatment) and/or exposed at $4^{\circ}C$ for 0, 4, or 8 weeks (chilling treatment) and then planted in plastic trays filled with media and grown in a greenhouse at $20^{\circ}C$ and under 16 h photoperiod. In all species, no bulblet propagated by tissue culture sprouted without chilling or hot water treatment due to dormancy. For dormancy breaking, $GA_{4+7}$ hot solution treatment increasing sprouting by 55-96%, whereas distilled water or GA was not effective in sprouting. Chilling treatment for 4 weeks induced sprouting by 50-70% in L. cernuum and L. leichtlinii, whereas 8 weeks was needed for sprouting of L. hansonii and L. hansonii for. mutatum. Combined treatment of hot water and chilling treatments synergistically promoted sprouting. Especially, in L. cernuum and L. hansonii, $GA_{4+7}$ hot solution soaking prior to chilling for 4 weeks promoted sprouting by 35-45% compared with the reverse order. Enlargement of bulblets resulted from increase in fresh weight and diameter was promoted by the treatments that increased the sprouting percentage of bulblets. Only in L. cernuum, shoots emerged from bulblets soaked in hot $GA_{4+7}$ solution or chilled at $4^{\circ}C$ and shoot emergence rate was highest in bulblets soaked in hot $GA_{4+7}$ solution and then chilled for 8 weeks. From these results, the most effective method for bulblet sprouting and enlargement was to soak in hot $GA_{4+7}$ solution and then chill for 4 weeks in L. hansonii, hansonii for. mutatum, and leichtlinii, and to soak in hot $GA_{4+7}$ solution and then chill for 4 weeks in L. cernuum and tsingtauense.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.449-462
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• 2012

The objectives of this study were to measure the range of motion for joints and muscle activation of upper limb for flower arrangement tasks for physical rehabilitation and to test horticultural therapy programs using flower arrangement tasks for improving upper limb function of the patients with stroke. Major flower arrangement tasks were classified with eight tasks (cutting 1, thick stem; cutting 2, thin stem; fixing 1, long stem; fixing 2, short stem; rolling a leaf; bending 1, thick stem; bending 2, thin stem; and winding, using a wire) based on the occupational analysis. When eight male university students (mean age $24.1{\pm}2.5$ years) conducted the eight flower arrangement tasks, range of motion for joints and muscle activation of upper limb were measured by a 3D motion analyzer and electromyography, respectively. Based on the results of the range of motion and muscle activation of upper limb, horticultural therapy programs using flower arrangement tasks (total 33 sessions) for improving upper limb function of the patients with stroke was conducted at a rehabilitation hospital, Seoul, South Korea and then the range of motion, grip strength, and upper limb function of the patients were tested. Among the eight flower arrangement tasks, cutting 1, winding, and bending 1 induced the highest value for the range of motion in joints of shoulder, elbow, and wrist, respectively (P < 0.001). In terms of muscle activation, eight flower arrangement tasks performed in this study showed various patterns of muscle activation and several muscles were simultaneously used for each task (P < 0.001). In addition, thickness and length of the materials used in a task had a prominent effect on the range of motion for joints and muscle activation of upper limb (P < 0.001). The stroke patients had positive effects for their range of motion of upper limb (shoulder, forearm, and elbow), grip strength, and overall upper limb function through the horticultural therapy program. Thus, this study suggested that flower arrangement tasks would be a potential horticultural activity for physical rehabilitation program. It would be interesting to apply a customized horticultural therapy program using flower arrangement tasks according to the symptoms of patient for physical rehabilitation.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.442-448
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• 2012

Many outbreaks of food-borne illnesses have been associated with the consumption of fresh vegetables and fruits contaminated with food-borne pathogens. Contaminated medium, manure and irrigation water are probable vehicles for the pathogen in many outbreaks. The aim of this study was to determine the potential transfer of Escherichia coli and Bacillus cereus from medium and soil fertilized with contaminated compost or irrigation with contaminated water to the edible parts of lettuce. Moreover, survivals of the two pathogens on lettuce contaminated medium, soil and irrigation water were estimated. Lettuce seeds were planted in medium contaminated with 7.5 log colony forming unit (CFU)/g of E. coli and B. cereus. Seedlings grown in the contaminated medium were transplanted in soil fertilized with contaminated pig manure compost or uncontaminated soil. Contaminated irrigation water with E. coli and B. cereus at 8.0 log CFU/mL was applied only once on the plant by sprinkle irrigation and surface irrigation. Although E. coli and B. cereus in medium and sprouted lettuce after planting seeds were reduced as time passed, these pathogens survived in seedling raising stage for extended periods. The numbers of E. coli and B. cereus in lettuce grown on contaminated soil were detected over 4.0 log CFU/g for 21 days. The numbers of E. coli and B. cereus in lettuce applied by sprinkle irrigation were higher than those of surface irrigation by 5.0 log CFU/g. Our results indicated that contaminated medium, soil and irrigation water can play an important role in the presence of food-borne pathogens on vegetables.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.165-171
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• 2011

Plant growth retardants reduce the plant height by inhibiting stem elongation in Lilium davuricum. To investigate the plant hormones related to stem elongation, we sprayed 50 $mg{\cdot}L^{-1}$ diniconazole to young plants of L. davuricum and quantified the contents of endogenous gibberellic acids (GA) and abscisic acid (ABA). In GA biosynthesis, L. davuricum had not only the early C-13 hydroxylation ($GA_{19}{\rightarrow}GA_{20}{\rightarrow}GA_1$) pathway resulting in $GA_1$ as the active form but also the non C-13 hydroxylation (NCH, $GA_{12}{\rightarrow}GA_{24}{\rightarrow}GA_9{\rightarrow}GA_4$) with $GA_4$ as the active form. However, the main pathway was NCH because $GA_4$ concentration of 55 $ng{\cdot}g^{-1}$ dry wt was much higher than $GA_1$ content of 0.23 $ng{\cdot}g^{-1}$ dry wt in control plant. Diniconazole inhibited GA biosynthesis through NCH pathway from its early stage. $GA_{12}$ content decreased by diniconazole up to 6% level of that of control and this effect continued to $GA_4$. Diniconazole reduced $GA_{12}$ content by 12.7 $ng{\cdot}g^{-1}$ dry wt, whereas that of control plant was 213.8 $ng{\cdot}g^{-1}$ dry wt. ABA content decreased up to one third of control by diniconazole application. From the contents of endogenous $GA_4$, $GA_1$, and ABA in this study, we could conclude that diniconazole reduces the plant height by inhibiting $GA_4$ biosynthesis in L. davuricum.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.385-391
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• 2012

The growth of terminal shoots of persimmon (Diospyros kaki) was analyzed during the first two months from the time of bud sprout to understand the dynamics of their early growth. Field-grown, mature 'Fuyu' and 'Nishimurawase' trees were used in a three-year study at two locations in Gyeongnam province. The growth of terminal shoots was most active from late April, about 10 days after foliation, to early May, followed by a gradual decline by late May. The increase in leaf area continued unabated throughout May. The weight of a flower bud increased slowly until early May and rapidly after flowering. Although its extension growth had been ceased by late May, dry weight (DW) of a terminal shoot continued to increase almost linearly throughout May due to shoot thickening and continued growth of leaves and fruits. In late May, the leaves and the stem accounted for more than 60% and less than 20% of total DW of a shoot respectively; fruit proportion increased to 7 to 17% by then. Relative growth rate (RGR) of the terminal shoot was higher than 213 $mg{\cdot}g^{-1}{\cdot}d^{-1}$ in late April, but declined to less than 63 $mg{\cdot}g^{-1}{\cdot}d^{-1}$ in late May. Like the pattern of seasonal changes in RGR, net assimilation rate (NAR) of the shoots decreased from 1.9 to 2 $mg{\cdot}cm^{-2}{\cdot}d^{-1}$ to 0.5 to 0.8 $mg{\cdot}cm^{-2}{\cdot}d^{-1}$. An early-season 'Nishimurawase' did not differ from a late-season 'Fuyu' in RGR and NAR during the first two months of growth. The early growth of the shoots was affected mainly by the reserves redistributed from permanent organs, however, environmental conditions at the time was also involved.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.655-665
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• 2014

The effect of modified atmosphere packaging (MAP) on kohlrabi (Brassica olerace L. gongulodes group)'s quality and antioxidant molecule during storage was examined to determine the optimal film package for maintaining freshness. To extend shelf life, MAP was tested using PE $50{\mu}m$ and oriented polypropylene (OPP) films with oxygen transmission rate (OTR) at 3,000, 10,000, $15,000mL/m^2/day/atm$. The OPP film packaging with modified oxygen transmission rate showed a delay in a weight loss and extended storage period. The package with OTR 3000 attained the desired gas composition of $O_2$ 3.2-6.7 kPa and $CO_2$ 13.1-19.8 kPa, in storage at room temperature. Kohlrabi stored in this package showed the lowest weight loss and the highest visual quality. Deterioration and off-odor were developed more rapidly in PE $50{\mu}m$ towards the end of the storage at room temperature. However, there are no differences among OTR films in visual quality and off-odor until 60 days at cold storage. Vitamin C content of kohlrabi was reduced rapidly in OTR 15000 with high transmission rate and showed less loss in PE $50{\mu}m$ and OTR 3000 in both room temperatures and cold storage. Results revealed that an OPP film with OTR 3000 extended the shelf life of kohlrabi in storage with maintained quality and vitamin C.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.577-583
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• 2014

Benzyladenine (BA, 99% purity), MaxCel$^{(R)}$ (1.9% BA), Fruitone (3.5% NAA), MaxCel$^{(R)}$ + Fruitone, a nd s imazine were applied postbloom as fruitlet thinning agents to mature 'Hongro' and 'Fuji' apple (Malus domestica Borkh.) trees. BA and MaxCel$^{(R)}$ were applied at $100mg{\cdot}L^{-1}$ a.i. while Fruitone at $0.1mg{\cdot}L^{-1}$ a.i. and simazine at $400mg{\cdot}L^{-1}$ a.i. All PGRs were applied at 8 days after full bloom (DAFB, 6 mm fruit diameter) in both cultivars, while simazine was treated twice at 7 and 14 DAFB. In 'Hongro', the number of total fruit set per flower cluster in terminal buds was 1.67, 1.84, and 1.81 in MaxCel$^{(R)}$ + F ruitone, MaxCel$^{(R)}$, and simazine applications, respectively, when compared with 2.35 of water control. These reductions in fruit set were mainly attributed to the increased ratio of defruited clusters by the thinning agents. In 'Fuji' apple, the number of total fruit set per flower cluster in terminal buds was 1.29, 1.60, and 1.76 in MaxCel$^{(R)}$ + Fruitone, Fruitone, and MaxCel$^{(R)}$, respectively, when compared with 2.56 of water control in 'Fuji' apple. The addition of Fruitone to the MaxCel$^{(R)}$ promoted the thinning efficacy in both cultivars, compared to MaxCel$^{(R)}$ only. The thinning efficacies were similarly observed with lateral flowers in both cultivars. A significant increase of fruit weight by the postbloom thinning treatments was observed only in the BA application in 'Hongro', while the effect was observed in BA and MaxCel$^{(R)}$ in 'Fuji'. While the soluble solids content increased in the BA, MaxCel$^{(R)}$ and MaxCel$^{(R)}$+Fruitone treatments in both cultivars, other fruit quality attributes were not affected by the application of post-bloom thinning agents.

• Journal of Internet Computing and Services
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• v.21 no.5
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• pp.139-148
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• 2020

Infectious diseases have long plagued mankind, and predicting and preventing them has been a big challenge for mankind. For this reasen, various studies have been conducted so far to predict infectious diseases. Most of the early studies relied on epidemiological data from the Centers for Disease Control and Prevention (CDC), and the problem was that the data provided by the CDC was updated only once a week, making it difficult to predict the number of real-time disease outbreaks. However, with the emergence of various Internet media due to the recent development of IT technology, studies have been conducted to predict the occurrence of infectious diseases through web data, and most of the studies we have researched have been using single Web data to predict diseases. However, disease forecasting through a single Web data has the disadvantage of having difficulty collecting large amounts of learning data and making accurate predictions through models for recent outbreaks such as "COVID-19". Thus, we would like to demonstrate through experiments that models that use multiple Web data to predict the occurrence of infectious diseases through LSTM models are more accurate than those that use single Web data and suggest models suitable for predicting infectious diseases. In this experiment, we predicted the occurrence of "Malaria" and "Epidemic-parotitis" using a single web data model and the model we propose. A total of 104 weeks of NEWS, SNS, and search query data were collected, of which 75 weeks were used as learning data and 29 weeks were used as verification data. In the experiment we predicted verification data using our proposed model and single web data, Pearson correlation coefficient for the predicted results of our proposed model showed the highest similarity at 0.94, 0.86, and RMSE was also the lowest at 0.19, 0.07.

• Korean Journal of Environmental Agriculture
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• v.18 no.3
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• pp.236-244
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• 1999

A feasibility study was performed to examine the agronomic application of treated sewage on paddy rice culture by field experiment. The domestic sewage was treated by the constructed wetland system which was in subsurface flow type and consisted of sand and macrophyte. The effluent of the wetland system was adjusted to maintain the total nitrogen concentration below $25mgL^{-1}$ and used for irrigation water. Four treatments include (1) irrigation of treated sewage after concentration adjusted with conventional fertilization (TWCF), (2) irrigation of treated sewage after concentration adjusted with half of the conventional fertilization (TWHF), (3) irrigation of treated sewage after concentration adjusted without fertilization (TWNF), and (4) irrigation of treated sewage as it was without fertilization (SWNF). These cases were compared to the control case of tap water irrigation with conventional fertilization (Control). Generally, addition of the treated sewage to the irrigation water showed no adverse affect on paddy rice culture, and even improvement was noticed in both growth and yields. TWCF showed the best result and the yields exceed the Control in about 10%. Overall performance of the treatments was TWCF, Control, TWHF, TWNF, and SWNF in decreasing order. From this study, it appears that reuse of treated sewage as a supplemental irrigation water could be feasible and practical alternative for ultimate sewage disposal which often causes water quality problem to the receiving water body. For full scale application, further study is recommended on the specific guidelines of major water quality components and public health.