• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.152-155
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• 2003

Burcucumber (Sicyos angulatus L.), used as a medicinal or rootstock for cucurbitaceous crops have shown high variation in seed maturity and size. This study was carried out to determine the effect of seed maturity and size on seed germination, seedling emergence and growth of burcucumber, Seeds collected from a native site were divided into small, medium and large ones after sorted to mature and immature ones. Their germination, seedling emergence and growth were done in indoor and a green house. Mature seeds showed higher germination and seedling emergence rate than immature ones. Regardless of their maturity, medium. and small seeds showed higher germination rate than large ones. Medium and large seeds, however, had the greatest and the least seedling emergence, respectively. Seedling height, number of true leaves areas of cotyledons and true leaves except hypocotyl length were increased with increased seed size although were not affected by the maturity. Cotyledon, leaf, hypocotyl, root and their total dry weights were greater in large mature seeds than large immature ones while increased with increased seed size in both maturities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.80-84
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• 2002

In spite of simple and cheap cultivation method, water broadcast-seeded rice demonstrates uneven and unstable seedling establishment per unit land area and requires more herbicide and labor-input for weed control. Three experiments were conducted in a phytotron at 18$^{\circ}C$ to evaluate the adaptability of seed-mat mulching cultivation technologies in water seeded rice for the uniform seedling establishment and the inhibition of weed occurrence without herbicide application. Five different kinds of mat with different mesh sizes and fabric properties were tested. The emergence of rice was the highest in Lawn-mat treatment, being comparable with the control, in which seeds were sown without mat. The Lawn-mat also exhibited the lowest mat tension. Mat tension may influence the emergence of rice. And once it was soaked in water, it didn't maintain its original shape any more. The emergence rate of rice was the lowest in Safer-mat treatment. In Lawn-mat treatment, which was the most effective for rice emergence in the first study, the differences of emergence and seedling establishment of rice depending on the seeding position (upper, beneath, and between mats) treatments were negligible, while they were higher in dry seeds than in pre-germinated seeds treatment. The emergence as affected by the kinds of mat also showed the same trend when tested using barnyard grass. Depending on the kinds of mat, the inhibition effect of weeds was the greatest in Safer-mat and the poorest in Lawn-mat. These results strongly suggest the possibility that the uniform seedling establishment and weed management without chemical could be achieved simultaneously by seed-mat mulching through the combination of effective mat for the emergence of rice and another efficient mat for the inhibition of weed occurrence. This possibility was also tested in the field.

• 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.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.83.1-83
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• 2003

Rice seedling disease is one of major problems in water-seeded rice. This disease is known to be caused by several pathogen such as Pythium, Achlya, and Fusarium species. However, seedling disease of rice in water-seeded rice in Korea is not extensively studied. Pythium species have been isolated from Seosan, Yeoju, Icheon areas using Pythium selective media and their pathogenicity was investigated. All of the Pythium isolates showed strong pathogencity causing seedling emergence reduction in water-seeded rice. Seedling emergence was reduced to 0∼9％ at 10 days after inoculation of 23 Pythium isolates compared to 60％ of noninoculated control in a growth chamber. However, Fusarium species did not cause seedling emergence reduction in water-seeded rice. In contrast, when no water added into water agar or soil, the pathogen caused seedling rot two weeks after planting. These results indicate that Pythium species is a cause of seedling disease in water-seeded cultivation areas in Korea.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.103-110
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• 2010

This experiment was conducted to investigate seedling emergence and early growth of Monochoria vaginalis and Scirpus juncoides in the controlled-environment chamber maintained at different temperatures. Non-linear regression analyses of observed data against effective accumulated temperature (EAT) with the Gompertz and logistic models showed that the Gompertz and logistic models worked well in describing seedling emergence and early growth of both weed species, respectively, regardless of temperature. EATs required for 50% of the maximum seedling emergence and the maximum leaf number of M. vaginalis were estimated to be 69.3 and $131^{\circ}C$, respectively, while those of S. juncoides were 94.8 and $137^{\circ}C$, respectively. Models developed in this study thus were used to predict seedling emergence and early growth under elevated temperature condition. If rotary tillage with water is made on 27 May under $+3^{\circ}C$ elevated temperature condition, dates for 50% of the maximum seedling emergence and 4 leaf stage were predicted to be 1 June and 15 June for M. vaginalis and 3 June and 14 June for S. juncoides, respectively. As compared with current temperature, these dates are 1-2 days earlier for the seedling emergence and 3 days earlier for the early growth, suggesting that earlier application of herbicides is required for effective control of M. vaginalis and S. juncoides under elevated temperature condition in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.370-375
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• 1996

This study was conducted to find out the feasibility in direct seeded rice cultivation on the reclaimed saline soil. Seedling emergence was tested under the different application rates of rice straw and seeding depth, and also under combined treatments soil moisture regimes and seeding depth on saline soils in a greenhouse. The comparison of seedling stand and yield performance of rice in rotary till after broadcast seeding and in non-plow after broadcast seeding were tested on a field that reclaimed saline soil. Seedling emergence ratio in application of rice straw(4 and 6 tons /ha) was higher than that in non-application of rice straw. Seedling emergence and plant height were remarkably increased with the shallow seeding depth in the application of rice straw(4 tons /ha). The seedling emergence under proper soil moisture condition(25%) was higher than that under excess soil moisture condition(35%). Under proper soil moisture condition, the plant height was increased with the shallowed seeding depth. The number of seedling stand per m$^2$ in non-plow after broadcast seeding was larger than that in rotary till after broadcast seeding. Panicle number per m$^2$ in non-plow after broadcast seeding was much larger than that in rotary till after broadcast seeding and the yield showed the same trends as panicle number.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.460-464
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• 2003

White spunbonded fabrics has been utilized toy covering in rice seedling nursery. This study, therefore, was carried out to examine the effect of light quality on seedling emergence, growth, morphology, chlorophyll content and photosynthesis to get the information on the color of the fabrics. Blue, red and far-red lights were treated immediately after sowing seeds of three cultivars, Dongjinbyeo, Ilmibyeo and Daesanbyeo. Seedling emergence, growth and morphology, chlorophyll content and photosynthetic rate were measured. Seedling emergence rate of Dongjinbyeo and Daesanbyeo was low under far-red light treatment compared to those under blue and red light ones. Although the rate of Ilmibyeo was not different from three light treatments. Far-red light treatment showed similar response in plant height and leaf length, but yee light increased number of roots. Shoot and root dry weight was the highest in blue and red light treatments, respectively. Total dry weight, however, was the lowest under far-red light treatment. While chlorophyll content and photosynthetic rate of the three cultivars did not showed consistent response, those were the greatest under red light treatment, and were decreased in order of blue and far-red light treatment.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.321-328
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• 2003

Various presowing seed treatments have been used to enhance the rates of germination and afterward seedling emergence. Seeds treated by them occasionally have not shown the same rate in indoor and field. The presowing treatments considering germination mechanism and factors affecting germination should be totally included in indoor experiments so that the results drawn could be reproduced in the field. Seed drying after the treatments and field conditions after sowing especially able to show Phytochromemediated responses related to light treatment must be determined prior to force the treatments to seeds. After set up these prerequisites to promote the rates of germination and emergence, many seed treatments proposed so far must be fixed how to be done; alone, sequential and simultaneous.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.58-62
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• 2008

Utilization of carbon sources by Bacillus cereus D324, a biological control agent, and Pythium species, which causes rice seedling disease, was studied with the objective of increasing the efficacy of biological control by providing the biological control agent with specific beneficial carbon sources. D-galactose, D-sorbitol, and D-mannitol were poor carbon sources for Pythium spp. growth but were good for B. cereus D324 growth. Growth in a growth chamber of rice seeds coated with B. cereus D324 amended with specific carbon sources, such as D-galactose and D-sorbitol, showed significantly enhanced seedling emergence compared to seeds coated only with B. cereus D324. Field trials showed that both seedling emergence and yield increased, when the above specific carbon sources were added to B. cereus D324 in seed coating formulations. This result indicated that amending seed coating formulations with specific carbon sources could significantly increase seedling emergence and yield in the field.