• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.126-131
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• 1996

In this study effects of isolation distance, transplanting time of maternal plants, and bagging of flower head with the gauze-cloth bag on the outcrossing of burley tobacco (Nicotiana tabacum L.) were investigated. Also the effect of fertilizer level and control of the number of capsules per plant on seed production and quality were examined. A male sterile line. produced 0.3 to 3.8 capsules Per plant when it was Planted with normally flowering tobacco with the average outcrossing of 7.2 plants, ranging from 2 to 18 out of 20 plants. With the farther the isolation distance between maternal plants and pollen donor plant, the lower the outcrossing occurred. Outcrossing occurred even at the isolation distance of 312 m. When the maternal plants were transplanted 35 days after transplanting the pollen donor ones, the outcrossed plants were not decreased significantly. The bagging of the flower head with the gauze-cloth bas (#0.9∼ 1.0 mm) decreased the outcrossed plants significantly, but couldn't prevent the outcrossing completely. The seed amount per plant was higher in the highly fertilized cultivation. The number of seed capsules per plant affected significantly on seed yield and quality. When the seed capsules was controlled by 30 or 50 capsules per plant, the weight of 1,000 seeds and germination rate were higher than those with 70 or 90 capsules per plant. Key words : Nicotiana tabacum, outcrossing, bagging.

• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.463-470
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• 2000

For maximum seeding efficiency of a nozzle type seeder, the performance of the nozzle should be considered sufficiently. This study was carried out to investigate the optimum operating conditions of a seeder attached the vacuum nozzle which was modified syringe needle acting on the plug seedling tray and the seed plate. Such operating factors as the hole diameter of the nozzle (d), the distance from the nozzle tip to the bottom plate of seed hopper(D) the absorbing air pressure of the nozzle tip(P) the bounding height of seed from the vibrated bottom plate of seed hopper and the seeding speed were selected based on the weight of a grain of seed(W). The treated materials were pepper seed as the flat type, cucumber seed as the oval type and radish seed as the spherical type. The optimum operating conditions of the experimental seeder were revealed as follows: 1. The height of the seed bounding from the bottom plate of seed hopper and the distance from nozzle tip to bounded seed were 5 mm and 0.5 mm at all seeds. The hole diameter of the nozzle and the absorbing pressure for pepper seed, cucumber seed and radish seed was 0.45 mm, 0.65 mm. 0.65mm and 39.2 kPa, 88.3 kPa, 58.8 kPa, respectively. 2. The absorbing pressure P was represented as P=η.4W/$\pi$d$^2$ where η was 100. The seeding speed using a 128 cell tray was 2.4 cm/s which was same transfer as 2.5 trays per minute. 3. The maximum seeding rate in case of the pepper seed was 97% the cucumber seed was 95% and the radish seed was 100% under the optimum operating conditions of the seeder.

• Journal of Environmental Science International
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• v.11 no.2
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• pp.121-130
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• 2002

Compare to investigate the taxonomic utility of infragenera system and interspecific of Asian Geranium, we examined the fruit and seed morphology from 35 taxa. The fruit shape and seed's dispersal way did so that may divide subgenus or some part section to do could reason evolutionary trends. That is, at seed dispersal, the awns of section Geranium of subgenus Geranium, ramains attached at the top of rostrum, though fairy easily broken off, because seed increases awn's elasticity by diffusive way, it is long characteristic seed\`s dispersal distance, and subgenus Robertium observed that seed dispersal distance is short because it is no awn's elasticity by way that seed dispersal is gone as awn drops with rostrum. Also, section Geranium of subgenus Geranium and subgenus Robertium act role that awn keeps temporarily breed swerving with mericarp instead of bristle because section Tuberosa of subgenus Geranium is not bristled function that keep temporarily breed because mericarp bristled on base at seed dispersal do while. Therefore, is thought that is talon that when consider formation's development and function regarding this seed dispersal function, subgenus Geraniuum evolves more than subgenus Robertium. Seed morphology can divide by 2 subgenera(Geranium, Robertium) according to pattern of seed coat. and Seed's morphology characteristic(whole shape, color, form of seed apical and base, micropyle area, hilum area, chalaza, and position of seed hilum area), can distinguish some species, but is thought that is not reasonable as for discernment characteristic form and nature by repetition of characteristic form and nature. Especially, infrasection do in fruit and seed's morphology that is handling in this research that know to argue classification system and relationship by repetition of characteristic form and nature difficult. To all reliable truth, cytological, ecological, embryology, and molecular genetics research about talon is considered that should be achieved section Geranium that do not handle yet.

• Journal of Plant Biology
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• v.13 no.2
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• pp.15-20
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• 1970

The treatment of X-ray was manipulated with the large focus of X-ray which was produced the capacity of 90 kilovoltage and 30 milliamphere in the distance of 50 centimeter. The germination of each gruop irradiated with X-ray for 5, 6, and 7 seconds was more delayed in the growth of carrot seed than those of the control group. However the germination of each group irradiated with X-ray for 2, 3, and 4 seconds was rather accelerated than those of the control group. The irradiation of ultraviolet light was carried out in the distance of 20 centimeter by Toshiba germidicial lamp which appeared the wavelength of 2537A$^{\circ}$. The germination of each group irradiated with ultraviolet light for 9, 15, 20, and 40 minutes was more delayed than those of the control group, but the germination of carrot seed was accelerated by adequate dosage of ultraviolet light. Consuquently it was suggested for the author that the inhibited substance contained in carrot seed would be certain fatty substance, becasue the germination of carrot seed was more accelerated by the treatment of acetone than those of X-ray and ultraviolet light.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.2
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• pp.91-96
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• 2000

This research was concluded under dryland condition in Thrace region in 1994-1995 growing season. This experiment was arranged in randomised block design with three replications. Yield and some important yield components (plant height, number of pods per plant, number of seeds per pod and 1000 seed weight) were determined. According to the results, it can be concluded that the best sowing rate and row distance of chickling vetch for the region are $100\;seed/\textrm{m}^2$ and 20 cm, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.5
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• pp.235-240
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• 2003

The development of large area GaN substrates is one of important issues in expanding of GaN-based applications. In order to investigate the possibility, GaN thick films were grown by a sublimation technique, using MOCVD-GaN films grown on a sapphire as a seed-crystal substrate and a commercial GaN powder as a source material. The pressure in chamber under the fixed flow rate of $N_2$ gas and $NH_3$ gas was kept at 1 atmosphere and the effects of the various processing parameters such as the distance between source material and seed crystal, the temperature of top- and bottom heater and the growth time during the growth of GaN thick film were investigated. The growth feature and microstructure of the GaN thick films were observed by SEM and XRD. The optical bandgap properties and the defects were evaluated by the PL measurement. By these results, the growth conditions such as the distance between the GaN source and the seed substrate, the growth temperature and the growth time were determined for the satisfied growth of GaN thick films.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.37-37
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• 2018

We use two different methods for laboratory propagation from seed of lady's slipper orchid(Cypripedium macranthos Sw.); immature seed which also called green capsule or fully mature seed about 120~130 days from pollination. In green capsule culture, the seed pods should be collected within precisely right time. The right time of seed collection could be diverse under the wether conditions or nutritional factors of the plants. In fully matured seed culture, the more complicated procedures are needed to break the dormancy of the seed; thermal or chemical treatment. The seedlings in this study were easily germinated from immature seeds in Harvais medium; 53 days after pollination(DAP) in Cypripedium pubescens, DAP 65 in C. parviflorum and C. macranthos. The germinated seedlings were transplanted to hormone free media immediately to avoid abnormal growth of seedlings. When the seedlings have roots with a minimum length of around 2-3cm and have visible dormant buds, the seedlings were removed from the flask and stored in refrigerator for vernalization. To examine the correlation of seedlings and maternal plants, the 125 seedlings of C. macranthos were transplanted in the soil bed at a distance of 20-100 cm from mother plants on April 20. The survival rate of seedlings were 92% in 20 cm distance from the ripe plants, and 56 % in 100 cm distance. The seedlings which were transplanted near mother plants showed vigorous growth in plant height, leaf width, and especially dormant buds. Considering the existence of mycorrhiza which is a symbiotic association between a fungus and the roots of a orchid vascular, the various fungus from mother plants could affect the growth of the seedlings. These results indicate the possibility of high and stable production and practical industrialization of endangered lady's slipper orchids.

• The Korean Journal of Ecology
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• v.20 no.4
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• pp.265-274
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• 1997

All landscapes are mosaics of habitat patches of different types. Therefore, there are always edged between habitat patches in a landscape. Forest animal has an important role in vegetation development and maintenance by seed dispersal around forest. Movement of animals depends on the spatially heterogeneous structure and pattern of vegetation landscapes because each animal has special habitats in a landscape. Especially, forast edge with high permeability and prey density is one of the important habitats to the animals. Therefore, understanding the ecological characteristics of the forest edges as a corridor connecting mosaic vegetation patches is necessa교 새 establish the strategies for the nature conservation and sustainable vegetation management. Under this idea, we examined the animal influenced on pine seeds as one of the method of monitoring the animal activity in mosaic vegetation. Man-made mosaic vegetations including open, edge and inner forests were carefully selected in the rural landscape. We carried out predation test on pine seeds during one year. A result was that damages on seed was more significant at forest edge than inner and open forest. Pine seed on seedbeds was mainly attacked by squirrels and mice than birds. Pine seed was damaged by squirrels in different types of vegetation by seasons. Rate of seed predation at forest edge was, in special, higher than that of other sites. According to this results, it is suggested that the relationship between animal behavior and spatial vegetation structure relating to human impact such as the distance from settlement to vegetation appeares to be in the rural vegetation landscape.

• Animal cells and systems
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• v.3 no.1
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• pp.29-39
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• 1999

Current data on reproductive characters of endemic and native species are essential to provide a strategy for the conservation of these species. Red pine (Pinus densiflora Sieb. & Zucc.) is one of the dominant, native tree species in Korea, but its reproductive ecology is not well-known. In 1997, the pattern of variation in cone and seed yields contributing to the conservation of declining populations of red pines was examined. Plant height and dbh were measured, and several new cones were collected from each tagged tree after counting the number of cones on each tree. For a subset of cones sampled, the number of fertile scales, the number of seeds at three development stages (early/late aborted, and filled seed), seed wing size, wing color, and individual filled seed mass were measured. The three sites which differed significantly in mean plant size also differed in mean cone and seed production per plant. However further analyses showed that most variation in characters examined occurred among plants within sites, but not among sites. An average of 90% of the potential seeds on the cones aborted at an early developmental stage, demonstrating that early abortion is a major factor affecting the number of filled seeds per cone. Individual seed mass was the only character which exhibited significant variations among sites as well as among trees within sites. Individual seed mass was overall negatively correlated with both the percentage of late abortion and the number of old cones per plant, suggesting that both the past and current years' reproductive activities have caused variations in seed mass. The potential dispersal distance of red pine seeds is quite large. However, wing loading was correlated with seed mass and number in a complex pattern across the sites. Distribution of seeds with varied colored wings differed among sites and among trees within sites. These results suggest that red pines at different sites might possess different strategies to cope with selection pressures acting during the final phase of reproduction, from seed dispersal to establishment. Then the ‘fitted’ red pine trees at each site should be identified and managed to conserve or restore populations.

• Progress in Superconductivity
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• v.8 no.1
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• pp.8-15
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• 2006

The size of the superconducting domains and the critical current density inside these domains have to be enhanced for most of cryomagnetic applications of melt-textured YBCO bulks. To enlarge the size of the domains we studied the multi-seeding technique based on a well-established procedure for preparing high quality YBCO monoliths using self-made SmBCO seeds. The distance between the seeds was optimised as a result of the investigation of the effects of various seed distances on the characteristics of the grain boundary Junctions. The influences of a-b plane intersections and c-axis misalignments were researched. Thereby, a small range of tolerance of the misorientations between the seed crystals was found. Field mapping was applied to control the materials quality and the superconductor's grain structure was investigated using polarisation microscopy. YBCO function elements with iou. seeds in a line and an arrangement of making type (100)/(100) and (110)/(110) boundary junctions, respectively, were processed. The trapped field profile in both sample types shows single domain behaviour. To demonstrate the potential of the multi-seeding method a ring-shaped sample was processed by placing sixteen seeds in a way to make both (100)/(100) and (110)/(110) grain junctions at the same time. The results up to now are very promising to prepare large single domain melt-textured YBCO semi-finished products in complex shapes.