• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.380-387
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• 2013

The objective of this study is to investigate the effect of elevated $CO_2$ and temperature on the phenology and reproductive ecological characteristics of Bupleurum latissimum. We measured characteristics of 4-year-old B. latissimum grown under control (ambient $CO_2$+ambient temperature, 340~370 ppm) and treatment (elevated $CO_2$+elevated temperature, 690~770 ppm) conditions in a glass house. The period of flowering, fruit appearance and fruit maturing was earlier by 4, 1, 2 days, respectively, under elevated $CO_2$ and temperature. The comparative weight of a single ripe fruit, all ripe fruits and total ripe and unripe fruits was higher per control than treated plants. However the other characteristics, such as no. of peduncle, matured fruits, total fruits per plant and fruit setting rate per plant of B. latissimum were not significantly affected by elevated $CO_2$ and temperature. The germination rate of B. latissimum was higher in control than in treatment plants. These results showed that the phenology of B. latissimuin might be well suited to an earlier growing season, and the response of reproductive characteristics of B. latissimuin is negatively influenced by global warming.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1039-1044
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• 2003

We investigated the changes in saponins during the cultivation of soybean sprout. Crude saponin content was 4.15mg/g in germinated soybean and reached its peark (5.33mg/g) in soybean sprout cultivated for six days. Saponin content in the cotyledon, stem, and root of the soybean sprout cultivated for six days were 4.17, 7.46, and 7.45mg/g, respectively. Soyasaponins extracted from the soybean sprout were analyzed with LC-electrospray ionization (ESI)-mass spectrometry, in which a reverse phase $C_18$ column was used for separation of saponins. In the soybeen sprout, group B saponin, I, II, III, IV, and V increased 7, 2, 1.4, 8.7, and 3.3 fold, respectively, compared to those in the soybean seed. Group B saponin I, II, III, IV, and V in the stem of the soybean sprout were 10.53, 1.45, 10.49, 5.72 and 8.14 fold the level of those in the cotyldon, respectively. In the root, the contents of group B saponin I, III, IV, and V were 5.54, 2.77, 4.86 and 9.73 fold, respectively, higher than those in cotyledon, but the content of group B saponin 2 was 2.96 fold less than that in cotyledon. These results indicate that the biosyntheses of group B saponins are differentially regulated in growing soybean sprout.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.3
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• pp.153-157
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• 2008

This study was conducted to select some effective organic materials for supplying mineral nutrients at the later red-pepper growing period under organic farming system, and to evaluate the application effect. Nutritional characteristics of organic materials, nitrogen release pattern during liquefying the selected organic materials, and crop growth were examined. Among 18 organic materials, meals such as soybean, rapeseed, cottonseed, and sunflower seed except for gluten had greater nitrogen content. Total nitrogen content liquefied solution of the mixture of organic materials and molasses or yogurt was measured after 7 days of the liquefying, thereafter, the mixture of rapeseed meal and yogurt showed the highest nitrogen, reaching about $3,000mg\;L^{-1}$. Selected liquid manure, mixture of rapeseed meal and yogurt, was applied 8 times to red-pepper plants with fertigation or foliar application. Total nitrogen of leaves at 150 days after transplanting was the highest (4.4%) in the treatment of foliar application of the selected liquid manure, whereas shoot dry weight and fresh fruit yield were the greatest in the treatment of fertigation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.289-295
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• 2001

Experiments were conducted to find out the optimum level of slow release N fertilizers when total amounts of nitrogen required throughout the growing season in paddy were applied in the soil of seedling box. To evaluate the emergence rate and growth of rice seedlings, five levels of Meister (MS) 10, MS S10, and latex coated urea (LCU) which are equivalent to 0, 40, 60, 80, and 100kg N h $a^{-l}$ were mixed in soil of the seedling box. Emergence rate differed depending on the fertilizers and N levels; in MS 10 plots the emergence rate was 40.8% at 40kg N h $a^{-l}$ and no seedlings were emerged at the higher levels, in MS S10 plots higher than 80% at all the N levels, and decreased with the N levels from 70.0% at 40 kg N h $a^{-l}$ to 59.5% at 100kg N h $a^{-l}$ of LCU. Seedling started to wilt at 40 kg N h $a^{-l}$ of MS 10 and 80 and 100 kg N h $a^{-l}$ N of LCU on the 8th day after sowing, while seedling growth was normal at all the levels of MS S10. Field performance of rice was evaluated at the 0, 30, 60, 90, 120kg N h $a^{-l}$ of MS S10 applied in the soil of seedling box and N was not applied in paddy. Grain yield at 90 and 120kg N h $a^{-l}$ of MS S10 was similar to conventional urea split application (120 kg N h $a^{-l}$), but significantly higher compared to 30 and 60kg N h $a^{-l}$ of MS S10. Fertilizer N recovery decreased with N levels and the N recovery at 90 kg N h $a^{-l}$ of MS S10 and conventional urea split application were 62.2 % and 44.2%, respectively, with similar grain yield. The optimum level of MS S10 to be applied in seedling box seems to be about 90 kg N h $a^{-l}$ considering grain yield, price of fertilizer, labor applying fertilizer, and fertilizer N recovery.d fertilizer N recovery.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.314-320
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• 1984

Effects of phosphorous fertilizer on the growth habit and yield of monoculm and branch types of two leading sesame varieties was investigated. The photosynthetic rate of at each growing stage was high at the flowering stage. The photosynthetic rate of monoculm sesame variety, Pungnyeon was high prior to flowering stage, while the Kwangsan variety, branch type was high after the flowering stage. The level of phosphate were most effective in increasing photosynthesis when standard level of fertilizer was applied in both varieties. Kwangsan variety showed higher photosynthetic rate per unit area, higher NAR, and CGR and higher LAR and RGR at the maximum flowering stage than the Pungnyoeon variety. Those characters attained maximum level when standard levels of phosphorous fertilizer were applied. The protein and oil content of seeds were higher in Kwangsan variety compared with Pungnyeon. However, the carbohydrate of seeds was high for Pungnyeon variety. The highest protein content was attained when standard level of fertilizer were applied. The oil content appeared to increase as the level of applied fertilizer increased. The results suggest that the vegetative growth and seed yields of sesame may be enough with present level of fertilizers. However, higher amount of phosphorous fertilizer may be required to increase the oil content of sesame seeds.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.302-306
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• 2005

This Study was Conducted in 3 glasshouse to examine the Possibility for cultivation of plug seedlings using four growing media containing recycled PET-bottle-particles (PBT) as a medium component. Plug seedlings of 'Seokwang' tomato were grown in media containing $100\%$ PBT, $100\%$ peatmoss, or $50\%$ $PBT+50\%$ peatmoss. A commercial plug medium (Tosilee) was used as the control. All seeds were sown in 128 cell plug trays on July 12, 2004. Seedling growth was measured at 30 days after sowing. Percent seed germination was greater than 95% in all treatments. Plant height, shoot fresh and dry weights, leaf area, and hypocotyl length were the greatest in the control treatment. Root length and weight were the greatest in the $100\%$ PBT treatment, which had a medium pH of 7.3. Leaf area and shoot dry weight were greater in the $50\%$ $PBT+50\%$ peatmoss treatment, than in the $100\%$ PBT treatment, while they were the smallest in the $100\%$ peatmoss treatment. No toxicity symptoms caused by the use or PBT had been observed in any treatment. The results suggest a possibility of recycled PBT, a valuable reusable resource, to be used as a component for medium amendments in horticultural transplant production.

• Journal of Aquaculture
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• v.20 no.1
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• pp.26-30
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• 2007

Resources of the sea cucumber, Stichopus japonicus in the west coast of Korea are decreasing sharply due to overfishing and severe marine pollutions. Artificial seed production and release of this species need to be conducted to maintain sea cucumber stock in the region. In this study, to provide basic information for such works, reproductive cycle of sea cucumber collected from Anmyondo in the region was histologically studied for a year from October 2004 to September 2005. This species was dioecious, and its gonads was composed of a number of gametogenic follicles. The gonadosomatic index (GSI) was reached the maximum in June (7.91), and the minimum in October (0.42). The main spawning occurs between June and August. The reproductive cycle of the sea cucumber could be divided into five stages: multiplicative stage (January to March), growing stage (March to April), mature stage (April to July), spawning.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.95-100
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• 1977

To get a basic information for improving Korean's pattern of comsuming red pepper and the possibility of its industrial production, consumer's ways of red pepper processing and his present dietary habits were surveyed and the results are follows; (1) Korean's daily consumption of red pepper was on the average 9.2 g on the basis of the whole dried red pepper. (2) The tendency of evading the home drying method was increased; 72.22% in urban community and 50.4% in rural community purchased the dried red pepper in the lump yearly. The household purchasing the fresh red pepper and using the home drying was 27.8% in urban community and 49.6% in rural community, so one third of urban household was still using the home drying method. The case of dependence on tine drying factory was no more than 2.6%. (3) Drying method was mainly sun drying which done on the poor circumstance like as the street side without the proper equipment of drying. Home process of red pepper by housewife was 70.8%, and the old, housekeeper were only 7.3% respectively. (4) The hygienic sense in the drying was rare; 68.8% was not washed and 51.9% of decayed red pepper was eaten. (5) Koreans prefered the strong pungency, deep red color and fine powder form. (6) While the 45.5% of seed was collected by second hand dealer and made use of as resources of edible oil, it was not used effectively due to complexity of its collection system. (7) While 40.1% desired the improvement of red pepper dietary life, 41.1% distrusted the present commercial red pepper powder on the market. From the results above, we conclude the fact many households have still hygienically poor red pepper processed at home, in spite of the red pepper is one of the most important spices in Korea. Considering the growing urban population, reduction of unemployed labor due to the increasing nuclear family and hygienic problems caused by the serious pollution, the improvement of red pepper processing method is urgently required. And it is believed that red pepper has a good prospect to be processed on the industrial scale in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.229-235
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• 2012

This study was conducted to investigate the climatic factors affecting bud phenology of Pinus densiflora provenances. Data were collected from Jungseon, Chungju and Jeju plantations which were parts of the 11 provenance trials established by Korea Forest Research Institute in 1996. The 36 provenances were included in this trial ($33^{\circ}30^{\prime}{\sim}38^{\circ}08^{\prime}$ in latitude and $126^{\circ}30^{\prime}{\sim}129^{\circ}20^{\prime}$ in longitude). The bud swelling date and bud burst date of the provenances were investigated from March to May in 2004 in two-day interval. The four geographic factors and fifteen climatic factors of the test sites and provenances were considered in this study. Canonical correlation analysis was conducted to examine the major factors affecting the bud phenology. Our results suggested that the major factors affecting the timing of bud swelling and burst are the differences in latitude, longitude, extremely low temperature (during December-February), extremely high temperature (during November-February) and annual mean growing days between test plantation and provenance. The provenances with lower winter temperature than that of plantation showed the faster bud swelling and bud burst. Based on these results, the implication on the seed transfer of P. densiflora was discussed.

• Journal of the Korean earth science society
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• v.30 no.4
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• pp.454-463
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• 2009

In this study, from January 2006 to February 2009, we observed 107 ice spikes formed in a natural state, and analyzed their environment. We developed an experimental device to reproduce ice spikes in laboratory and successfully made 531 ice spikes. We analyzed the process of the formation and the principle of how those ice spikes grow through videotaped data of the formation in the experiment. In the natural world, when the surface of water and the lower part of a vessel begin to freeze, a vent (breathing hole) develops at the surface where an ice is not frozen; this vent serves as the seed of an ice spike. It is assumed that the volume expansion of ice in the vessel which occurs when water freezes makes the supercooled water go upward through the vent and becomes an ice bar called an ice spike. In the laboratory, however, when distilled water is poured into an ice tray cube and kept in the experimental device for about one and a half hours at a temperature of -12- $-13^{\circ}C$, a thin layer of ice then begins to develop on the surface of the water, the vent is formed, and ice spikes form for about 10-30 minutes. These spikes stop growing when the end becomes clogged. Ice spikes can be described as falling into seven categories of shape, with the apex type topping the list followed by the slant type in the natural state and the vertical type predominating in the laboratory.