• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.132-132
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• 2022

The application of direct seeding cultivation reduces time, labor, and cost. However, this application often has poor seedling establishment and leads to lower yield as compared to transplanting system. The tolerance to anaerobic and low temperature germination is important to improve seedling establishment and the wide-spread application of direct seeding method. This study was carried out to evaluate the responses of three japonica cultivars to different temperatures (15℃, 18℃, 21℃, 24℃, and 27℃) and different flooding levels (1 cm, 4 cm, 7 cm, 10 cm) during germination and seedling development. The mean survival percentage significantly increased (P<0.05) when the flooding level decreased and when temperature increased. There were significant effects of the interaction between temperature and water depth on survival percentage and seedling height. When temperature decreased from 27℃ to 15℃, the germination duration significantly increased from 6.4 days to 16.3 days while the germination speed, survival percentage, and seedling height decreased from 5.3 seeds day^-1, 61.9% and 190.6 cm to 2.2 seeds day^-1, 33.2%, and 47 cm, respectively. The increase in temperature under submergence condition was associated with the increased expression of Amy3D and ALDH2a but the decreased expression of ADH1 and PDC1. The results of this research would be used for further studies and breeding programs to improve rice seedling establishment and the application of direct seeding cultivation.

• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.503-510
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• 2013

This study was conducted to determine the optimum intensity of root pruning and the initial seedling size of 1-year-old Quercus serrata for producing 2-year-old healthy seedlings. Large( > 26 cm hight) and small size ( < 24 cm hight) seedlings were pruned their root by the length of 5, 10, and 15cm and then transplanted on nursery. Stem height, root-collar diameter(RCD), height to RCD ratio(H/D ratio), shoot dry weight(DW) and root development were measured during first growing season after transplanting. Seedling size and pruning intensity influenced on shoot growth such as height, RCD, H/D ratio and DW after transplanting. In addition, the development of lateral roots such as number, length, DW and diameter were affected by the seedling size. Taproot pruned by 15cm was shown excellent above-ground growth in large seedling group, but pruned by 10 and 15cm showed respectively better shoot growth in small seedling group. Large seedlings increased their above-ground growth, taproot regrowth, and number of lateral roots more than those of the small seedlings. But the length and DW of lateral roots were increased in the small seedlings. In conclusion, in order to produce high quality 2-year-old seedlings, it is important to produce large size of Q. serrata seedlings. Also root pruning length of 1-year-old Q. serrata was reasonable on 15 cm in taller than 26 cm or 10cm in less than the height.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.3
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• pp.147-151
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• 1990

The purpose of this study is to clarify the relation of survival rates of seedling plants under grown orchardgrass populations and control by the difference cutting frequency. The orchardgrass populations investigated in this study have passed for 10 years after establishment. Cutting frequencies were 3, 4 and 5 times in a year. This experiment was conducted from April to October, 1989 at the experimental field of Institute of Agricultural Development, Yonsei University. The results are summarized as follows: 1. The survival rates of seedling plants decreased by the days after sowing. The final survival rates of seedling plants were 7.8%, 38.9% and 33.8% in 3, 4 and 5 cuttings, respectively. 2. Relative light intensity indicated highly possitive correlation with relative survival rates of seedling plants and negative correlation with plant length of orchardgrass populations in 4 and 5 cuttings. 3. The frequency distribution of survival seedling plants at 177 days after sowing were showed high values in seeding spots near the adjacent plants of 3 cutings, but in the middle of seeding spots between adjacent plants of 4 .and 5 cuttings, respectively. 4. The plant length of seedling became longer towards the seeding spots near the adjacent plants but the number of tillers increased slightly up to the middle of seeding spots between adjacent plants in all cutting frequencies.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.290-295
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• 1998

Presowing treatements to seed are reasonable for elevating the seedling production efficiency. This experiment was carried out to determine the effects of $GA_3$ [0 (water) : 0.01 mM] and light qulaity (red : white) simultaneously treated before sowing on seedling emergence and growth of tobacco (Nicotiana tabacum L.) cv NC 82 and Burley 21. Red or white light was illuminated 12 hours a day while seeds of the cultivars were imbibed with either water or $GA_3$ 0.01 mM for 3 days. Seedling emergence was measured up to 20 days after sowing but morphological characters and dry weights were done 40 days. The seedling emergence rate of cv NC 82 was more affected by light quality and $GA_3$ pretreatments than that of cv Burley 21. Light quality more influenced the rate than $GA_3$ while red light or water imbibition enhanced the rates of the two cultivars compared to the other treatement. Although mean plant height and leaf number per seedling were nearly equal between the treatements, red light declined leaf area per seedling of cv Burley 21 of which seeds were imbibed in water but white light decreased the areas of both cultiars of which seeds were soaked in $GA_3$solution. Shoot dry weight was greater in cv NC 82 but less in cv Burley 21 pretreated with red light, and root dry weight showed the reverse result in white light, meaning that presowing light and $GA_3$ treatments could be changed the seedling development and growth of tobacco.

• Journal of Sericultural and Entomological Science
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• v.2
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• pp.63-71
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• 1962

This work was to develope a more simple producing method of mulberry seedling with lower cost than the normal grafting method and the conclusions were found as; 1. There was no difference for the production of the seedling root when the young mulberry branch was graved in soil at the time it grown as 60∼80cm height. 2. It was found that the best result was obtained in case of 15 to 20 young branches of a mulberry shoot were graved instead of whole of them. 3. The seedling root quality of the clay soil graved was found better than the sand soil used, but root producing quantity was found as the same. 4. The fertilizing at the time of the young branch graving was not effective and also the continual fertilizing seemed not to be effective. 5. The seedlings root production was found that Kairyo Nezumigaeshi was best and Ichihei, Suwon Daeyop, Shimano-Uchi, Suwon No.3 and Suwon No.4 were followed of it. But Rosoh was found as poor. Morus alba L. was found as a better Species than Morus Lhou(Ser) Koidz and Morus bombycis Koidz for the production of the seedling root and its quality.

• Journal of Biosystems Engineering
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• v.36 no.1
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• pp.40-47
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• 2011

Image analysis algorithm for the quality evaluation of ginseng seedling was investigated. The images of ginseng seedling were acquired with a color CCD camera and processed with the image analysis methods, such as binary conversion, labeling, and thinning. The processed images were used to calculate the length and weight of ginseng seedlings. The length and weight of the samples could be predicted with standard errors of 0.343 mm, and 0.0214 g respectively, $R^2$ values of 0.8738 and 0.9835 respectively. For the evaluation of the three quality grades of Gab, Eul, and abnormal ginseng seedlings, features from the processed images were extracted. The features combined with the ratio of the lengths and areas of the ginseng seedlings efficiently differentiate the abnormal shapes from the normal ones of the samples. The grade levels were evaluated with an efficient pattern recognition method of support vector machine analysis. The quality grade of ginseng seedling could be evaluated with an accuracy of 95% and 97% for training and validation, respectively. The result indicates that color image analysis with support vector machine algorithm has good potential to be used for the development of an automatic sorting system for ginseng seedling.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.229-232
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• 1998

This study was conducted to determine the properties of seedling plate papers currently used in commercial production, then to get basic information for manufacturing new seedling plate paper. Imported seedling plate paper had high wet tensile and burst strengths in its usage circumstances. Wet tensile strength was very high with 38.7% of dry tensile strength. Wet burst strength was also very high with 62.4% of dry burst strength. The seedling plate paper contained about 30% of synthetic fibers. It had 10 Gurley sec. in air permeability indicating effective movement of air. Seedling plate papers were' made in laboratory scale. For sufficient sizing degree, the addition of 0.5% AKD (alkylketene dimer) by weight was good enough. Additional amount of AKD more than 0.5% by weight caused strength loss even though improving sizing effect. The addition of wet strength reagent such as Finex-B 2% by weight resulted in good strength and air permeability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.4
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• pp.284-288
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• 2001

Water deficit is a serious constraint to soybean [Glycine max L. (Merr.)] production in rainfed regions of Asia, Africa, and America. This study was conducted to develop a simple and effective screening method for drought tolerance in soybean. Fifteen soybean cultivars, eight identified to be drought-tolerant and seven drought-sensitive in previous studies, were used for the evaluation of drought tolerance under the new screening conditions. The seedling screening method was consisted of a treatment in a PEG solution and drought treatment in parafilm-layered pots. 5-day-old seedlings were treated in a 18% PEG solution for 4 days and their wilting and hypocotyl browning were recorded. Three seedlings grown in a parafilm-layered pot containing peat moss were drought-stressed by withholding water from the third day after seedling emergence, and root and seedling growth were examined. Degree of drought tolerance were rated based on seedling vigor in the PEG solution and drought-stressed parafilm-layered pots, and also on the penetration ability of roots through parafilm layer. Most of seedlings of the drought-tolerant cultivars showed higher vigour and root penetration than those of the drought-sensitive cultivars under the new screening conditions. Our results indicate that the new method can be used as a simple and effective screening procedure for drought tolerance in soybean breeding programs.

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.307-313
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• 1997

Seed germination test done in laboratory does not coincide with field emergence in general. The experiments were carried out to examine the effect of priming and $GA_3$, treatment to seeds of Platycodon grandiflorum; Codonopsis lanceolata and C. pilosula on lapsed time to first seedling emergence, seedling emergence, morphological characters and growth and the cause of poor emergence of C. pilosula. No-treatment as Control (water), priming or $GA_3$ treatment was done with only distilled water for 2 days, $CA(NO_3)_2$ 150 mM for 2 days or $GA_3$ 0.1 mM for 3 days, respectively. Seedling emergence rate was counted every 2 days but morphological characters and dry weight of shoot and root were measured on 38 days after sowing. Their internal seed structures were examined with Scanning Electron Microscope. C. pilosula had poorer seedling emergence rate than P grandiflorum and C. lanceolata showing nearly same rate: Compared to the other treatment (s) P. grandiflorum displayed higher rate in priming and $GA_3$, treatments but C. lanceolata or C. pilosula did the greatest rate in only $GA_3$ or priming treatment, respectively. $GA_3$ treatment to seeds of P. grandiflorum and C. lanceolata shortened the lapsed time to seedling emergence in comparison with Control, 2-days water imbibition before sowing. In all the species plant height and number of leaves per seedling became shorter and less in priming treatment than the other treatments except plant height of C. Pilosula while their hypocotyl length was nearly same in all treatments. Although priming treatment had nearly similar effect to morphological characters, $GA_3$ treatment forced greater shoot, root and aftermath total dry weight per seedling. Poor seedling emergence of C. pilosula was caused by its seed defect like cleavage or lack of embryo, poor development of embryo and endosperm or their separation.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.135-142
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• 2003

This study was conducted to clarify on germination rate enhancement effect and to develope the growing seedling method on Sorbus commixta Hedl. The results were follows; The optimum temperature of stratification and germination of mountain ash was $5^{\circ}C$ the seed germination rate in wet stratification with sand at $5^{\circ}C$ for 90 days was 22.6% and the highest germination of 78.9% was observed when seed was soaked in BA 200ppm for 20 minute after stratification for 90 days at $5^{\circ}C$. The highest germination of large chinese hawthorn was 11.1% when seed was soaked BA 50ppm for 20 minute after stratification 90 days at $5^{\circ}C$. Emergence ratio in box raising seedling and pot seedling showed high, 93 and 95%. Root length and dry root weight in pot seedling for 50 days showed higher than that of direct seedling and box raising seedling, Plant height and dry leaf weight in box raising seedling showed higher than that of pot seedling and direct seedling. The growth increment of seedling was high between 40 days and 50 days after seedling. The excellent seedling of mountain ash was produced in pot seedling for 50 days.