• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.390-395
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• 2006

Effects of exogenously foliar applied glycine betaine (GB) on the growth and contents of osmolyte in tomato seedling was investigated. Plants treated with exogenous glycine betaine induced better biomass production and plant height during chilling stress than the untreated plants. The total soluble sugar contents in GB foliar-applied plants lower than that of untreated plants 28 days after foliar application. Total water soluble protein contents in GB foliar-applied plants did not change 28 days after chilling stress. In untreated plant, it decreased rapidly in the beginning of chilling stress. Proline contents in untreated plants rapidly increased by the beginning of chilling stress, and then slightly decreased during the next 3 weeks. However proline contents in GB foliar-applied plants did not change during the 28 days chilling stress period. The results suggest that foliar application of GB is a effect methods to increase the chilling tolerance of tomato seedlings in protected cultivation system at low temperature season.

• BMB Reports
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• v.40 no.3
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• pp.373-381
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• 2007

Seed storage proteins (SSPs) are important for seed germination and early seedling growth. We studied the accumulation and degradation profiles of four major Arabidopsis 12S SSPs using a 2-DE scheme combined with mass spectrometric methods. On the 2-DE map of 23 dpa (days post anthesis) siliques, 48 protein spots were identified as putative full-length or partial $\alpha$, $\delta$ subunits. Only 9 of them were found in 12 dpa siliques with none in younger than 8 dpa siliques, indicating that the accumulation of 12S SSPs started after the completion of cell elongation processes both in siliques and in developing seeds. The length and strength of transcription activity for each gene determined the final contents of respective SSP. At the beginning of imbibition, 68 SSP spots were identified while only 2 spots were found at the end of the 4 d germination period, with $\alpha$, subunits degraded more rapidly than the $\alpha$ subunits. The CRC $\delta$ subunit was found to degrade from its C-terminus with conserved sequence motifs. Our data provide an important basis for understanding the nutritional value of developing plant seeds and may serve as a useful platform for other species.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1163-1170
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• 2009

The clam, Gomphina melanaegis, which is commonly called the sandy beach clam because of its habitat, is a valuable organism in the sandy coast of East Sea, Korea. It is frequently observed in large populations between 0.5 and 5 meters. We have released 50,000 seedling, ranging from the diameter of approximately 3 mm, 2007, and 1,000,000 seedling, ranging from the diameter of approximately 0.2 mm, plus 100,000 adult individuals, ranging from the shell length of approximately 20~40 mm, 2008 at Jinha beach. The spawning period of G. melanaegis, was from June to August, and the main spawning occurred in July. This investigation was carried out to elucidate population distribution on the stocking area of sandy beach clam, G. melanaegis. The relationship between shell length and ring radius in each ring was investigated as a regression line. The relationship between the shell length and shell height of released young clam was SH=1.0105SL-4.7764 ($R^2=0.7905$). The relationship between the shell length and total weight of released young clam was $TW=0.0013SL^{2.3966}$($R^2=0.71$). It draws a deduction that the ring of this clam was produced once a year during the duration between June and August.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.512-518
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• 1994

One of most laborious work in rice farming is transplanting of rice seedling which has been required preparation of nursury bed and care of seedling during one month period. In this research, direct seeding in dry paddy(DS) was practiced to compare with traditional tansplanting(TP) in Suwon and Milyang. Growth stages in DS were delayed as its planting time was about 36 days later than TP. Heading stage of DS at Suwon was delayed about 15 days as compared to transplanting culture. Rice yield in DS was decreased 8.2%(Suwon) and 0.11%(Milyang), repectively. Working-hour saving in DS was about 34.0%(Suwon) and 54.0%(Milyang). Production cost of DS was decreased 19%(Suwon) and 29% (Milyang), repectively. Amount of rice production per a unit working-hour in DS could incresed 37%(Suwon) and 113%(Milyang) compared to that of TP, respectively. Therefore, DS was decreased little in rice yield, but it could save working hour and production cost, significantly. Warm region like Milyang had more advantage in DS than Suwon. But, DS needs varietal selection for better emergence in low temperature, and more research in weed control and water management.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.115-122
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• 1996

One of the most laborious work in rice farming is transplanting of rice seedling which has been required preparation of nursery bed and care of seedling during one month period. In this research, direct seeding in dry paddy(DS) and direct seeding in wet paddy(WS) were practiced to compare with traditional transplanting(TP) in Suwon. Growth stages in direct seeding were delayed as its planting time was about 21 days later than those of TP. Heading stage of direct seeding at Suwon was delayed about 9 days as compared to transplanting culture. Rice yield was not different between the seeding practises. Working-hour saving was about 17％(DS) and 28％(WS). Production cost of direct seeding was decreased 20％(DS) and 32％(WS), respectively. Amount of rice production per a unit working-hour in direct seeding could increase 14％(DS) and 39％(WS) compared to that of TP, respectively. Therefore, direct seeding could save significantly working hour and production cost without reducing rice yield. WS was more effective than DS in saving labor and production cost. Direct seeding was not efficient method in input of farming energy and agricultural chemicals.

• Journal of Biosystems Engineering
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• v.26 no.4
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• pp.379-384
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• 2001

To enhance the smooth graft-taking of grafted seedlings, the excessive evapotranspiration from grafted seedlings just after grafting should be avoided. A measurement system of the evapotranspiration rate of grafted seedling under artificial lighting was set up to investigate the effect of physical environment on the evapotranspiration and graft-taking characteristics of grafted seedlings quantitatively. The evapotranspiration rate of grafted seedlings affected by relative humidity and light intensity were analyzed using the measurement system. The hypocotyl of watermelons (Citrullus vulgaris cv. Sweetdew, Hungnong Seed Co.) was slantly cut and then inserted into a hole on the stem of rootstock (Lagenaria siceraria cv. FR-King, Hungnong Seed Co.). Grafted seedlings were healed and joined for 5 days under cool-white fluorescent lamps (FL20SEX-d/18, Keumho Electric Co.) with photoperiod of 12h$.$d$\^$-1/ except dark period for one day after grafting in a closed graft-taking enhancement system developed by Kim(2000). The evapotranspiration rate and graft-taking of grafted seedling at air temperature of 23$\^{C}$ and air current speed of 0.1m$.$s$\^$-1/ was highly affected by relative humidity. But light intensity showed higher effect on the stem length of scion than relative humidity. In conclusion, it was suggested that relative humidity should be controlled at higher than 90% with photosynthetic photon flux of 50$\mu$mol$.$m$^2$$.$s$\^$-1/ to increase the survival of grafted seedlings and to produce healthy seedlings.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.175-182
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• 2010

North American ginseng seedlings (Panax quinquefolius L.) were grown in pots in heated greenhouses, in a cool greenhouse, or in the field, in 11 experiments at various times over 16 years. Crop establishment, dry matter partitioning, photosynthesis, radiation use efficiency and carbon budget were measured and/or calculated in some years. Once the seedling canopy, of about $20\;cm^2$ per seedling, and a leaf area index of 0.37, was established, about 40 days after germination, full canopy display lasted about 87 days. Only 16.6% of the incoming solar radiation was intercepted by the crop, the remainder falling on the mulched soil surface. Total and root dry matter accumulations in the cool greenhouse and in the field were about double that in the heated greenhouses. Partitioning of dry matter to roots (economic yield or harvest index) in the cool greenhouse and in the field was 73% whereas it was 62.5% in the heated greenhouses. The relationship between root dry matter and radiation interception during the full canopy period was linear with growth efficiencies of $2.92\;mg\;MJ^{-1}$ at 4.8% of incoming radiation and $0.30\;mg\;MJ^{-1}$ at 68% of incoming radiation. A photosynthetic rate of $0.39\;g\;m^{-2}\;h^{-1}$ was attained at light saturation of about $150\;{\mu}mol\;m^{-2}\;s^{-1}$ (7.5% of full sunlight); dark respiration was $0.03\;g\;m^{-2}\;h^{-1}$, about 8.5% of maximum assimilation rate. Estimates of dry matter accumulation by growth analysis and by $CO_2$ uptake were similar, 6.21 vs. 7.62 mg $CO_2$, despite several assumptions in $CO_2$ uptake calculations.

• The Korean Journal of Ecology
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• v.8 no.1
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• pp.15-19
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• 1985

A number of field surveys have been performed in larch (Larix leptolepsis) forest floor in which any seeding of this species never find ther. In laboratory work, aqueous extracts from leaves, roots and stems of larch were provided and used to bioassay. Among them, germination and seedling growth of selected species were the most inhibitory in leaves extracts. Though germiation percentage of a species showed high compared with control, its dry weight after a given period grown were clearly low. The results due to be considered by allelopathic effect. And syringic acid and p-hydroxybenzoic acid were identified by HPLC from larch leaves. It is assumed that these phenolic acids affect on other species as allelochemicals of larch.

• Journal of Aquaculture
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• v.1 no.1
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• pp.25-39
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• 1988

The flounder reared in captivity matured and spawned when the water temperature gradually increased to $14\~15^{\circ}C$ from $12^{\circ}C$ during winter and the diurnal photoperiod changed from 10L/14D in winter season to 14L/10D in spring. The eggs spawned naturally by reared spawners in captivity during the first half of a spawning period were superior in quality to those spawned during the later half. It would be better to use the eggs of the first half for the mass production of the seedlings.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.125-140
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• 1997

This experiment was carried out to investigate the effects of compost mixed with microorganism compost fermented for the production of high quality plug seedlings of tomato and red pepper. The results are summarized as follows. As a result of compost analysis, EC value was increased with increment of microorganism compost supplemented but lowered gradually in the late period of seedlings growth, pH value of microorganism compost fermented was 9.3 which is strong alkalinity. In the plot of 30 percent of microorganism compost fermented early growth of tomato seedlings was better in terms of plant height, leaf area and total dry weight. However, early growth of red pepper seedlings was shown in the plot of supplemented with 20 percent of microorganism compost fermented. The higher the mixing rate over 60 percent of micrroganism compost fermented to the soil used retarded the seedlings growth regardless of tomato and red pepper.