• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.73-78
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• 1983

In order to investigate the relation between weather factors, soil water, and tobacco yield grown by nonnulching and mulehing cultivations, a regression analysis was conducted for data collected from 8 years (1971 to 1978) for a flue-cured variety of Hicks. The soil water was calculated by Smith's method. 1 . Tobacco yield was largely correlated to soil water deficit during draught time for nonmulclung cultivation; $Y=6.146+8.6185\times-0.0925$\times2(R=0.935)^{***})$ 2. Tobacco yield was more largely correlated to soil water in flexible draght time interval than in fixed time interval during maximum growing phase.3. This field test was supposed that the optimal soil water condition was 65%field caps city. In this condition tobacco yield was 197. 1-216.5kg/10a for non-mulching cultivation. But the soil water deficit in draught season was little matter for mulching cultivation. The relation between xield and evaporation during May to June was Y: -1199.55+9.4 353$\times$:O. 0155$\times$2 (R=0.904") Maximum tobacco yield was expected to 223.6-251.4kg/10a for mulching cultivation. 5 . Tobacco required high temperature and light even in drying season (maximum growing phase) for mulching cultivation.tion.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.2
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• pp.35-41
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• 2009

The impacts of climate change on paddy irrigation requirements for Nakdong river basin in Korea have been analyzed. The HadCM3 model outputs for SRES A2 and B2 scenarios and International Water Management Institute $10'{\times}10'$ pixels observed data were used with kriging method. Maps showing the predicted spatial variations of changes in climate parameters and paddy irrigation requirements have been produced using the GIS. The results showed that the average growing season temperature was projected to increase by $2.2^{\circ}C$ (2050s A2), $0.0^{\circ}C$ (2050s B2), $3.7^{\circ}C$ (2080s A2) and $2.9^{\circ}C$ (2080s B2) from the baseline (1961-1990) value of $21{\circ}C$. The average growing season rainfall was projected to increase by 15.2% (2050s A2), 24.2% (2050s B2), 41.4% (2080s A2) and 16.7% (2080s B2) from the baseline value of 900 mm. Average volumetric irrigation demands were projected to decrease by 3.7% (2050s A2), 7.0% (2050s B2), 10.2% (2080s A2) and 1.4% (2080s B2) from the baseline value of $1.25{\times}10^9\;m^3$. These results can be used for the agricultural water resources development planning in the Nakdong river basin for the future.

• The Korean Journal of Ecology
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• v.26 no.2
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• pp.59-64
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• 2003

We examined the effects of fertilization [control (C), 200 kg N ha^{-1} + 25 kg P ha^{-1}$ (LNP), and 400 kg N $ha^{-1} + 50 kg P ha^{-1}$ (HNP)] on fine root (＜ 2 mm diameter) dynamics using monthly soil coring method in a 39-year-old Pinus rigida plantation of central Korea. The average fine root biomass (live + dead) (kg $ha^{-1}$ $\pm$ SE) during the first growing season for C, LNP, and HNP was 1301 $\pm$ 54, 1084 $\pm$ 47, and 1328 $\pm$ 22, respectively. The fine root production (kg $ha^{-1}$ $\pm$ SE) was 2394 $\pm$ 128 for C, 2048 $\pm$ 101 for LNP, and 2768 $\pm$ 150 for HNP, respectively. Over the same period, fertilization treatments had impact on N and P concentrations of live fine root. Nitrogen and P inputs (kg $ha^{-1}$ $yr^{-1}$) into the soil through fine root turnover for C, LNP, and HNP were 16.6 and 0.9, 17.2 and 0.9, and 24.1 and 1.6, respectively. There were no significant differences in fine root biomass and production during the first growing season after fertilization. However, fertilization increased fine root N and P concentrations, and in consequence resulted in increased N and P inputs into soil through fine root turnover.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.1-7
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of flue-cured tobacco as soon as possible. The data of eight chemical and five physical properties were collected from "Analysis of physical and chemical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 through 2006. Data of climatic factors from April to July in 10 districts were collected from Korea Meteorological Adminstration. Except for yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, in nicotine content, and in filling value, 90% in total nitrogen content, and 70% in total sugar content. These results suggest that the regression equations may be useful to predict the average content of twelve grades for eight chemical and four physical properties by climatic factors during the growing season of flue-cured tobacco at the beginning of August.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.8-13
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of burley tobacco as soon as possible. The data of six chemical and five physical properties were collected from "Analysis of chemical and physical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 to 2006. Data of climatic factors from April to July in 6 districts were collected from Korea Meteorological Adminstration. Except for total nitrogen, total nitrogen/nicotine and yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, 95% in nicotine content, and 90% in filling value. These results suggest that the regression equations may be useful to predict the average content of twelve grades for four chemical and four physical properties by climatic factors during the growing season of burley tobacco at the beginning of August.

• Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.35-47
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• 2024

The aim of this study was to analyze the income and productivity of seaweed farmers based on farmed land ownership status. This research was conducted in three provinces on the Sulawesi Island which are ranked among the 10 largest seaweed producers in Indonesia: Central Sulawesi, South Sulawesi and Southeast Sulawesi. The twelve study sites were determined based on 5 special criteria and 792 respondents fulfilled the criteria for seaweed farmers. Data were collected through field surveys and analyzed using qualitative and quantitative methods. Results showed that the seaweed farming areas are considered as private property with 4 types of marine land tenure or ownership status: own land, inherited land, leasehold land and purchased land. The productivity of seaweed farming land had a positive value greater than 1 in South Sulawesi and Southeast Sulawesi, and a positive value of less than 1 in Central Sulawesi. Seaweed cultivation in Central Sulawesi has not been managed effectively. At all sites, the maximum number of growing season cycles was 5 cycles/year. Optimal growing season conditions gave the highest marginal returns at 2-3 cycles/year with additional costs exceeding additional income for more than 3 cycles/year.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.235-241
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• 2017

This study was carried out to estimate growth characteristics of Kimchi cabbage cultivated in two different growing seasons and three transplanting dates in the greenhouses, and to create a predicting model for the production of Kimchi cabbage based on the growth parameters and climatic elements. Kimchi cabbages were transplanted three times at intervals of two weeks in spring and autumn growing seasons. Sigmoidal models for the estimation of fresh weight (Fw) was designed with days after transplanting, which were Fw=4451.5/[1+exp{-(DAT-34.1)/3.6}]($R^2=0.992$) and Fw=7182.0/[1+exp{-(DAT-53.8)/11.6}] ($R^2=0.979$), respectively. The relationship between fresh weight of Kimchi cabbage and growing degree days (GDD) was highly correlated, and the regression model represented by Fw=4451.5/[1+exp{-(GDD-34.1)/3.6}] ($R^2=0.992$) in spring growing season. The yield of Kimchi cabbage under spring and autumn growing season were estimated 11348.3kg/10a and 15128.2kg/10a, respectively, which were much different than outdoor culture each growing season, while greenhouse cultivation have shown similar results. To estimate the efficacy of prediction yield in Kimchi cabbage, we will need to supplement a predicting model, which was based on the parameters and climatic elements by the field cultivation.

• Journal of Ginseng Research
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• v.28 no.4
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• pp.196-200
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• 2004

This study was conducted to compare the root weight, yield, quality of fresh and red ginseng roots and crude saponin content in roots between fixing light transmittance(Control) and changing light transmittance(C.L.T.) during the ginseng growing seasons. The root weight in C.L.T. was higher than control by $35{\%}$ in early growth stage, $28{\%}$ in middle growth stage and $26{\%}$ in late growth stage in 6 years old ginseng plant. Root yield per 10a in C.L.T. was increased about $40{\%}$ as compared with that of control, also 1st and 2nd grade of fresh ginseng roots in C.L.T. was higher $(50.3{\%})$ compared with that $(12.9{\%})$ of control. The specific gravity of ginseng roots grown under the C.L.T. was exhibited the sig­nificant difference than control during the growing season in 4 and 6 years old ginseng plants. Red ginseng quality in C.L.T. was not only improved remarkably due to the increasement of heaven and earth grade red ginseng but also increased in crude saponin content than control. Therefore it needs to change the light transmittance(increasing light dur­ing low temperature periods and decreasing light during high temperature period) during the growing season for high yield and good qualities of ginseng roots.

• Food Science and Preservation
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• v.18 no.2
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• pp.199-207
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• 2011

Physico-chemical characteristics such as width, weight, color and aroma compounds of garlic from 9 different areas were analyzed. Also, antimicrobial activity was tested for their juices. Width of garlic bulb was larger in growing worm-season garlics (Jeju, Namhae, Hapcheon, Hampyeong and Muan) than those of cool-season garlics (Taean, Seosan, Uiseoung) and imported from China. But numbers of nuts were smaller in growing cool-season garlics than others. L color levels of garlics were 80.73~87.40 and a color level have not significantly difference in all samples, b color level was lower in growing Namhae ($20.79{\pm}1.20$) and Muan ($20.91{\pm}1.62$). 25~30 peaks obtained from aroma compounds analysis of various garlics. Among these compounds, 17 kinds of aroma compounds were identified by GC-MS. And, we showed that 15 kinds of compounds were sulfur containing aroma compounds. Diallyl disulfide was contained 34.90~60.54% in various garlic and the highest contents than other compounds in total compounds. It was detected the highest in China garlic but the lowest in growing Muan garlic. All of garlic samples showed antimicrobial activity against Strep. mutans, B. subtilis, E. coli. V. parahaemolyticus, Asp. flavus, and C. albicans. Especially antimicrobial activity was stronger against E. coli, and C. albicans. Antimicrobial activity was enhanced by sample addition volume and the highest in Namhae garlic sample.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.471-475
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• 1987

Some physiological analysis and the trend of a change in mineral nutrient contents in 2 years old ginseng plants were investigated for 10 times at 15 to 25 days interval from April 25th to October 10. The growth of leaf in size was completed by the beginning of June and that of stem in height by the late of June. The trend of a seasonal change in root weight showed a form of V letter, that is, the weight was de-creased until late of May and increased continuously thereafter up to September. However, the duration of root growth might be dependent on the defoliation. The growth of root in length begins from the beginning of June and stops in the beginning of August. Relative growth rate, net assimilation rate and crop growth rate were all negative values in just after shoot-emergence. The values showed a peak in May and decreased gradually thereafter. The leaf area ratio showed a peak of 76$\textrm{cm}^2$/g in May, and down to 30$\textrm{cm}^2$ /g in the beginning of October. The contents of nitrogen and potassium in aerial part of ginseng plants decreased at the late growing season, but increased on lime. No seasonal changes on phosphate and magnesium were observed. The contents of nitrogen, phosphate and potassium in root decreased rapidly at the maximum growing season for the aerial part and increased gradually thereafter. Whereas no changes on lime and magesium were observed during the growing season.