• Proceedings of the Korean Society of Crop Science Conference
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• 1988.02a
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• pp.66-67
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• 1988

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.9-14
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• 2010

Several presowing seed treatments have been used to facilitate the seed germination and seedling emergence. The study was performed to design a model of presowing seed treatments in Taraxacum platycarpum. Germination and seedling growth responses to temperature, drying, chilling, $GA_3$ and priming were investigated to know the optimum germination conditions and presowing treatment. The optimum temperature condition for germination and seedling growth were $15{\sim}20^{\circ}C$ at dark condition. The seeds exposed to infra red light, however, did not germinate. The moisture content of seeds dried at $35^{\circ}C$ for 3.5 hours was returned to the level of unimbibed seeds. The germination of seeds dried under dark condition was better than those dried under infra red light. Prechilling treatment imposed for 6 weeks showed higher germination rate than $GA_3$ treatment or priming. In field test, the highest field emergence was observed in the seeds dried after prechilled for 6 weeks and followed by drying followed by $GA_3$ > low temperature > $KNO_3$ priming. Imbibition with 0.1 mM $GA_3$ solution for 2 hours then drying at 35 for 3.5 hour under dark condition was effective to the practical presowing treatment for Taraxacum seeds.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.255-264
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• 1989

The minimum concentrations of organic solvents inducing phytotoxicity were investigated after spraying or flooding solvent solutions to annual plants. In the foliar treatment of upland test, solvents with high-boiling point or low-polarity induced severe phytotoxicity. Especially, aromatic solvents induced severe phytotoxicity. The most sensitive plant to phytotoxicity was soybean. In the pre-emergence treatment of upland test, the solvents with high-boiling point only induced phytotoxicity at high concentration. The degree of phytotoxicity induced by foliar spray in the condition of paddy field was similiar to that of upland test, but in the pre-emergence test, the former was more severe than the latter. Among 6 treatments, phytotoxicity induced by solvents was most severe in the pre-emergence test under the condition of flooding paddy field. Generally, alcohols induced severe phytotoxicity, especially, ethanol at 0.001%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.257-265
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• 1996

To obtain the basic informations necessary to develop the production technology of vegetable soybean seeds, this study was conducted at the National Crop Experiment Station, RDA, Suwon, Korea in 1993. Seeds of three vegetable soybean varieties, 'Mikawashima', 'Hwaeomputkong', and 'Seokryangputkong' produced at Pyeongchang, a highland in Korea and introduced from Japan were planted on April 20 in the field. The emergence rate among varieties was significanlty different. Emergence rate of seeds produced at Pyeongchang was higher by 7% than that of the seeds from Japan. Rate of pod infection by Phamapsis spp., brown spot by Septaria glycines, soybean mosaic virus(SMV), and downy mildew by Peronospora manshurica in the field was not different between locations. The growth characteristics, yield components, and green pod and grain yields were not different between locations. Therefore, it was proved that the production of vegetable soybean seeds with the better quality and higher emergence is possible in highland, Korea. possible in highland, Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.305-309
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• 1991

This experiment was conducted to investigate the effect of shattered grain by combine harvesting at the previous year on rice plant emergence at different planting methods and plant characteristics, The results are follows : Combine harvesting greatly influence on shattered grain of Samgangbyeo as Tongil variety (49.5kg/10a) compared to that of Nagdongbyeo as Japonica variety(27.8kg/10a), while Nagdong-byeo showed higher germination rate than Samgangbyeo, whether transplanted and direct seeded. Emergence of volunteer and seed mixture were lower in transplanted than in direct seeded. In variety test. Japonica variety showed higher emergence of volunteer rice and seed mixture than Tongil variety. Generally, no significant difference in yield components were observed with different varieties by the volunteer rice. But the volunteer rice caused by combine harvesting decreased culm length, panicle length, spikelet number, panicle number and ripening ratio. except l000-grain weights.

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.278-285
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• 2019

The experiment was implemented to gain basic data for stable proso millet (Panicum miliaceum L.) production through germination viability and establishment uniformity based on seed refining under seed selection with specific gravity of proso millet seed. Seeds of three proso millet cultivars were carefully selected by adjusting NaCl into 9 levels (1.000, 1.005, 1.010, 1.015, 1.020, 1.025, 1.030, 1.035, 1.04 g·L^-1), and their standard germination rate, seeding quality and field emergence rate were investigated. Proso millets showed heavier thousand seed weight as specific gravity high. In standard germination, all of the 3 cultivars of selected seeding showed at least 91% germination rate. With respect to the 1.040 g·L^-1 selection by specific gravity, 'Hwanggeum' had 98.9%, 'Ibaekchal', 99.4%, and 'Hwangsilchal', 98.9%, recording the highest. Seeding quality was investigated and it was found that, compared with the non-selected seeds, selected seeds had longer plant heights and averaged 2.0, 2.2 and 1.9 cm, respectably. In terms of leaf length, only 'Hwanggeum' and 'Ibaekchal' showed distinctive differences. No significance was found in stem diameter and SPAD. The seeds selected using specific gravity all had longer or heavier average root length, root weight and stem weight. Compared with non-selected seeds, the specific gravity of 1.040 g·L^-1 had longer root lengths of 2.9, 3.0 and 2.9 cm. 1.040 g·L^-1 was also found to have the heaviest root weight, and stem weight. The field emergence viability investigation found significance solely in the mean emergence time (MET) by the cultivar. High significance was found in percent emergence (PE) and emergence rate index (ERI) in the specific gravity for the selection of seeds. All of the three cultivars showed higher PE and ERI as specific gravity selection high. The 1.040 g·L^-1 specific gravity selection had the highest PE of 90.7, 85.3 and 92.8%. For productivity increase based on improved proso millet germination rate and enhanced establishment uniformity, it seems favorable to employ 1.040 g·L^-1 specific gravity selection using salt solution.

• Journal of Life Science
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• v.7 no.4
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• pp.347-354
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• 1997

Some attempts were made to investigate the gentic characteristics of the brown planthopper(BPH), Nilaparvata lugens Sta${\aa}$l, biotypes. In terms of egg and nymphal periods, egg hatcgability, emergence ratio, and population change of BPH and plant damage of rice cultivars by the infestation of BPH biotypes and their hybrid progenies in field conditions. The egg and nymphal periods of the three of BPH biotypes and their hybrid progenies on Dongjinbyeo with no resistance gene were shorter than on rice cultivars with resistance gene. But the periods of biotype-2(♀) X 2(♂) (E) on Samgangbyeo with Bph-1 gene and biotype-3(♀) X 3(♂)(I) on Mirying 63 with bph-2 gene were as short as on Dongjinbyeo. The egg hatchability and emergence ratio of the three Bph biotypes and their hybrid progenies on Dongjinbyeo were higher than on the other rice cultivars, and those of E on Samgangbyeo and I on Miryang 63 were as high as on Dongjinbyeo. In rice paddy field, biotype-1(♀) X 1(♂)(A)$\sim$I infested on Dongjinbyeo, E onSamgangbyeo, and I on Miryang 63 were increased their population densities remarkably in next generation. Dongjinbyeo infested by A$\sim$I, and Myryang 63 infested by I were hopperburned at 60 days after infestation and had a damage rating of 0.9. But Samgangbyeo infested by E was no hopperburn(damage rating: 7.3) though it showed high BPH population at 60 days after infestation.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.58.2-58.2
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• 2018

Theoretically, the magnetic helicity transport flux through the solar surface into the upper atmosphere can be estimated indefinitely precisely by magnetic field footpoint tracking if the observational resolution is infinitely fine, even with magnetic flux emergence or submergence. In reality, the temporal and spatial resolutions of observations are limited. When magnetic flux emerging or submerging, the footpoint velocity goes to infinity and the normal magnetic field vanishes at the polarity inversion line. A finite observational resolution thus generates a blackout area in helicity flux estimation near the polarity inversion line. It is questioned how much magnetic helicity is underestimated with a footpoint tracking method due to the absence of information in the blackout area. We adopt the analytical models of Gold-Hoyle and Lundquist force-free flux ropes and let them emerging from below the solar surface. The observation and the helicity integration can start at different emerging stages of the flux rope, i.e., the photospheric plane initially cuts the flux rope at different levels. We calculate the magnetic helicity of the flux rope below the photospheric level, which is eventually to emerge, except the helicity hidden in the region to be swept by the blackout area with different widths. Our calculation suggests that the error in the integrated helicity flux estimate is about half of the real value or even larger when small scale magnetic structures emerge into the solar atmosphere.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.73-77
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• 2014

Field and nutrient cultures of American ginseng (Panax quinquefolius L.) were used to establish foliar symptoms related to boron (B) concentration in leaves and soils, and to evaluate radish as a time-saving model system for B nutrition. Application of excess B, 8 kg/ha versus the recommended 1.5 kg/ha, to field plantings of 2-, 3-, and 4-yr-old American ginseng plants just prior to crop emergence caused, within 4 wk after crop emergence, leaf symptoms of chlorosis followed by necrosis starting at the tips and progressing along the margins. The B concentration in leaves of 2-4-yr-old plants receiving 1.5 kg/ha Bwas $30{\mu}g/g$ dry mass compared to $460{\mu}g/g$ dry mass where 8 kg/ha B was applied. Similarly, B concentration in soils receiving the lower B concentration was 1.8 mg/g dry mass and $2.2-2.8{\mu}g/g$ dry mass where the higher B concentration was applied. Application of 8 kg/ha B reduced the dry yield of 3rd-yr roots by 20% from 2745 kg/ha to 2196 kg/ha and 4th-yr roots by 26% from 4130 kg/ha to 3071 kg/ha. Ginseng seedlings and radish were grown under greenhouse conditions in nutrient culture with four B concentrations ranging from 0 mg/L to 10 mg/L. At 5 mg/L and 10 mg/L ginseng and radish developed typical leaf B toxicity symptoms similar to those described above for field-grown plants. Increasing B in the nutrient solution from 0.5 mg/L to 10 mg/L decreased, in a linear fashion, the root and leaf dry mass of ginseng, but not radish. Given the many similarities of ginseng and radish to B utilization, radish might be used as a timesaving model system for the study of B, and other micronutrients, in the slow-growing perennial ginseng.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.245-251
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• 1985

Distributions of seed weight were investigated with different seed sized peanut varieties planted at the same time, and germination and field emergence percentage, growth, and seed yield were compared among three seed sizes of four peanut genotypes. Field performance also was carried out to evaluate the effects of cotyledon removal on growth and yields in field with large and small seed-sized peanut varieties. The variation of seed weight of large seed-sized was wider than small seed-sized peanut variety. The larger seed showed the higher percent germination after 3 days cold treatment in laboratary and field emergence. The growth was not different with their sizes, while seed yield was related to seed size in small seed-sized genotypes. The growth of peanut such as main stem, internodes, and total branches was affected significantly by cotyledon removal, although the differences were not obvious after podding time, and in small seed-sized variety Oltangkong, the yields was decreased by cotyledon removal but not in large seed-sized variety.