• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.2
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• pp.89-95
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• 2003

The study of this experiment is focused on labor saving of healthy rice seedling production using PSF (polypropylene spunbonded fabrics) as thermal protection material. Several factors such as different compositions of nursery soil and PSF materials were tested to produce healthy rice seedlings. The inner thermal protection material in PE film (polyethylene film) showed $0.9-1.7^{\circ}C$ higher than that of PSF 40-100 $\textrm{gm}^{-2}$. The light transmittance-ratio also showed similar trends. It is considered that the appropriate PSF material density was 40 gm$\textrm{gm}^{-2}$ in accordance with economic values and healthy rice seedlings. Plant height and dry weight according to various nursery soil showed the rang-es of 8.5-14.2cm and 5.5-10.0mg, respectively. In composition of nursery soil, artificial soil combined with paddy soil was effective in producing healthy seedling for rice seedling production. The total sugar content also showed the difference between PSF 40, 60 $\textrm{gm}^{-2}$ PE film (0.43-0.52mg FW $\textrm{g}^{-1}$) and PSF 80, 100 $\textrm{gm}^{-2}$ (0.28-0.35mg FW $\textrm{g}^{-1}$) and it showed the same tendency among varieties as well as various nursery soil. These results demonstrate that PSF 40 $\textrm{gm}^{-2}$ economically affordable, and can be recommended as thermal protection material for producing good healthy rice seedling.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.125-139
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• 1996

The relationships between environmental factors and the establishment and growth of oak seelings were studied in the greenhouse. The early seedling performances of three oak species (Quercus mongolica, Quercus serrata, Quercus variabilis) were compared. Mean seed weight was the biggest in Q. variabilis, and the smallest in Q. serrata, and the germination rate was higher in Q. variabilis than in Q. mongolica and Q. serrata. The germination rate was significantly affected by seed weight class in Q. serrata, but not in Q. mongolica. Emergence of oak seedlings was similar in all three oak species, and especially the first leaf emergence increased about twenty days after germination. An experiment was designed using three environmental factors (light, soil moisture, fertilizer) to compare the response of the three oak species. Light and soil moisture significantly affected the seedling height growth of Q. variabilis, but the effect was marginal in Q. mongolica and Q. serrata. However, growth of seedling biomass was significant in all three oak species. In contrast, fertilizer did not affect seedling growth of any of the oak species. Q. variabilis is expected to grow well in large gaps because it is very sensitive and responds well to high light and high moisture conditions. Q. mongolica and Q. serrata are relatively tolerant to shade but may need gaps for the seelings to grow into saplings.

• Journal of Ecology and Environment
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• v.33 no.2
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• pp.133-139
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• 2010

Atmospheric $CO_2$ concentrations have increased exponentially over the last century and, if continued, are expected to have significant effects on plants and soil. In this study, we investigated the effects of elevated $CO_2$ on the growth of Pinus densiflora seedling and microbial activity in soil. Three-year-old pine seedlings were exposed to ambient as well as elevated levels of $CO_2$ (380 and 760 ppmv, respectively). Growth rates and C:N ratios of the pine seedlings were also determined. Dissolved organic carbon content, phenolic compound content, and microbial activity were measured in bulk soil and rhizosphere soil. The results show that elevated $CO_2$ significantly increased the root dry weight of pine seedling. In addition, overall N content decreased, which increased the C:N ratio in pine needles. Elevated $CO_2$ decreased soil moisture, nitrate concentration, and the concentration of soil phenolic compounds. In contrast, soil enzymatic activities were increased in rhizosphere soil, including ${\beta}$-glucosidase, N-acetylglucosaminidase and phosphatase enzyme activities. In conclusion, elevated $CO_2$ concentrations caused distinct changes in soil chemistry and microbiology.

• Ocean and Polar Research
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• v.44 no.4
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• pp.311-317
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• 2022

Seed germination and seedling growth of a halophyte, Suaeda japonica were examined to measure the effects of seed preservation periods and various soil compositions in the mudflat of Saemangeum, Korea. Seed germination declined from 74.30% to 44.30% as the preservation period increased from 4 months to 12 months. After 14 days of seeding, seed germination was lowest in sandy soil (SS) at 8.67% and highest in earthworm cast+leaf mold (EC+LM) at 67.33%, showing 4~5 times higher than SS. The average lengths of seedlings were 12.20 mm in SS and 42.20 mm in EC+LM, respectively. These results suggest that seed germination and seedling growth enhanced in the soil that has more organic matter. In the experiment mixing Saemangeum soil (SMS), seed germination was from 4.00% in SMS to 88.00% in the soil of SMS+EC+LM after 14 days. Similar growth patterns were observed in the length of seedlings from 5.00 mm in SMS to 49.60 mm in SMS+EC+LM. The present results indicate that a population of Suaeda japonica could be established by stimulating seed germination and seedling growth by the addition of organic matters such as EC, LM, and EC+LM in the Saemangeum mud flat.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.27-31
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• 1977

Experiments were conducted to investigate the effects of seed bed soils and soil pH on the rice growth and control of seedling rots. A 2:1 ratio mixture of clay loam and compost resulted in the best seedling growth and quality among the soils used. At soil pH between 4 and 5. no seedling rots occurred and plant growth was normal. At soil pH above 6, seedling rots occurred and characteristics of seedings was poor. Tachiga ren application before seeding or immediately after seeding reduced seedling rots significantly at the high soil pH.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.340-346
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• 2003

This study was carried out to improve cultivation techniques by low cost and labour saving in ginseng (Panax ginseng C. A. Meyer) seedling production, by elucidating proper ratio virgin soil and organic fertilizer, suitable height of front piller. The obtained results are as follows ; The optimal ratio of white decomposition of virgin soil and organic fertilizer was 10:1 for good yield of standard seedling, The fittest height of front piller was 150 cm because of both good seedling growth and yield. The cost for production of seedling of ginseng could be reduced by both optimal ratio of virgin soil, organic fertilizer and selection of front piller height.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.382-385
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• 2006

To know the effect of water treatment sludge (WTS) as a rice seedling culture soil, rice seeds are sown, germinated and grown on the culture soils mixed with different ratios of WTS to sand (100:0, 50:50, 30:70, respectively), and their growth effects was compared to that of control, commercial culture soil. When WTS is used as a culture soil for rice, the length and weight of the top part of rice seedling somewhat decreased than those of control treatment while their root length and weight in all WTS treatments significantly increased. Although phosphorus and potassium uptake of rice seedling in WTS treatments was slightly decreased, WTS treatment showed to develop root growth which is necessary in the seedling stage of all plane. Such a stimulatory effect on root growth of rice seedling was significant in the mixture ratio of 50% WTS to 50% sand.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.5
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• pp.9-18
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• 2014

London Convention on the prevention of marine pollution by dumping of wastes and other matter prohibits the deliberate disposal of paper mill sludges at sea. In order to explore the alternative plan on the prohibition of sludge disposal at sea, the biodegradable seedling pot was developed by mixing the sludge with old newspaper (ONP) in appropriate mixing ratios. The C/N ratio of the mixed sludge was below 20, leading to rapid deterioration of the organic matters composing the seedling pot. The increased ONP contents in the seedling pot resulted in the increase of pot thickness and thereafter in the decrease of pot density. Cellulose fibers in ONP promoted water absorption of the pot but AKD addition helped the seedling pot to repel water during raising seedling. Breaking length and burst strength of the seedling pot were improved by addition of wet strength additives but air permeability was a little diminished. Biodegradable rate of the seedling pot in a soil was accelerated by the attack of soil microbes at the beginning, and finally the pot was completely degraded in 150 days in a soil.

• Journal of Ginseng Research
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• v.18 no.2
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• pp.134-136
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• 1994

The effects of soil phosphorus level on seed emergence, seedling mortality, plant and root development of American ginseng (Panax quinquefolium L.) were evaluated in a newly planted commercial ginseng garden. Phosphorus levels were increased from 58 ppm to 100, 150 and 200 ppm with triplephosphate (0-45-0). Higher phosphate levels increased, seed emergence and reduced seedling mortality. Root length, diameter, fresh root weight and total leaflet length were not affected by phosphate levels.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.163-168
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• 1983

Effect of rice hull mulching and peat application on seedling yield of Panax ginseng was investigated in modified Yang-jig seedbed. Mulching and peat increased soil moisture content but effect was not additive. Seedling yield was positively correlated with magnesium organic matter, potassium especially with soil moisture and calcium. Straw mulching is expected to be superior for practice.