• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.152-156
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• 2001

This study was conducted to investigate the flower organ removal effect on Atractylodes macrocephala Koidz which was introduced from China. The results were summarized as follows; The plant height of Flower Organ Cutting(F.O.N.C.) treatment short by 1.7∼2.5 cm compared to Flower Organ Non-Cutting(F.O.N.C.) treatment. But number of stem and stem diameter of F.0.C treatment were similar to that of F.O.N.C. treatment. The fresh weight of above-ground part of F.O.N.C. treatment was decreased 48∼60% compare to F.O.C. treatments. The later was period of F.O.C., the higher was fresh weight of above-ground part. The growth of underground part was more F.O.C. at July 15 and Aug. 20 treatments than F.O.N.D treatment. The dry rhizome yield of F.O.C. at July 15 treatment was increased 40% compare to F.O.N.D treatment. Essential oil content of F.O.C. at July 15 treatment was increased 12% compare to F.O.N.D treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.1-4
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• 1988

This study was invesigated to find out the optimum planting densities of Sculellaria baicalensis GEORGE about growth characters, yield components and yield at 6 planting densities by direct sowing culture. The results obtained are summarized as follows ; Studying the correlationship, the highly negative significances were found between planting densities and dry wights of root, leaves and stem ; on the other hand, the highly positive significances were found between planting densities and plant hight, stem diameter, respeitively. Plant height was long in dense planting, and short in spacious planting by direct sowing culture. Stem diameter was thick in spacious planting, and was thin in dense planting. Length and dry weight of root per plant were decreased in dense planting and were increased in spacious planting by direct sowing culture. Quality and yield of dry root weight were highest in optimum planting densities (30${\times}$10cm ; 33plants/m$^2$) by direct sowing culture.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.325-328
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• 2012

A new Dendranthema grandiflourm 'My Sun' was developed at Gyeonggi-do Agricultural Research & Extension Services (GARES), Korea in 2009. 'My Sun' was initially derived from the cross in 2005 between 'Omega Time Orange', a potted chrysanthemum cultivar with orange single type, and 'Tasman', a potted chrysanthemum cultivar with white single type in 2005. The cultivar has single type flowers with yellow petals. Trial and evaluation was conducted from 2006 to 2009 for the selection of this variety, including a shading culture in spring and a retarding culture in winter. The flowering time of 'My Sun' was October 13th, and year-round flowering is possible by shading or lighting treatment. The diameter of flower is 21.0 mm. Numbers of flowers per stem and petals per flower are 34.4 and 20.4, respectively. Its leaf color was green (Green Group 137A) and plant height was 13.3 cm. Days to flowering under the short day treatment is about 42 in spring, and numbers of branch per plant was 3.4 ea in the winter. This cultivar was resistance to white rust and consumer's preference of new pot-mum is high level than control.

• Korean Journal of Plant Taxonomy
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• v.47 no.2
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• pp.100-105
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• 2017

A new species, Epilobium ulleungensis J. M. Chung (Onagraceae Juss), from Ulleungdo Island (South Korea) was described and illustrated. Among four taxa native to Ulleungdo Island (E. amurense Hausskn. subsp. cephalostigma (Hausskn.) C. J. Chen, Hock & P. H. Raven, E. hirsutum L., E. pyrricholophum Franch. Sav., and E. ulleungensis), E. ulleungensis has a unique tetragonal stigma, which is considered to be an intermediate form between clavate (E. pyrricholophum) or capitate (E. amurense subsp. cephalostigma) and 4-lobed stigmas (E. hirsutum). More importantly, this new species is clearly distinguished from the other three taxa distributed on Ulleungdo Island by its height (over 200 cm), decumbent stem, leaf shape, short, dense pubescent covering on the whole plant, large flower size, and a dark pink or red purple flower. According to the stigma shape and other characters, it was estimated that E. ulleungensis is a hybrid between E. hirsutum and E. pyrricholophum or E. amurense subsp. cephalostigma). The specific epithet "ulleungensis" was chosen because the new species was restricted to Ulleungdo Island.

• Journal of Radiation Protection and Research
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• v.48 no.3
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• pp.131-143
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• 2023

Background: This study examined the detection limit of thyroid screening monitoring conducted at the time of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 using a Monte Carlo simulation. Materials and Methods: We calculated the detection limit of a NaI(Tl) survey meter to measure ¹³¹I accumulation in the thyroid gland of children. Mathematical phantoms of 1- and 5-year-old children were developed in the simulation of the Particle and Heavy Ion Transport code System code. Contamination of the body surface with eight radionuclides found after the FDNPP accident was assumed to have been deposited on the neck and shoulder area. Results and Discussion: The detection limit was calculated as a function of ambient dose rate. In the case of 40 Bq/cm² contamination on the body surface of the neck, the present simulations showed that residual thyroid radioactivity corresponding to thyroid dose of 100 mSv can be detected within 21 days after intake at the ambient dose rate of 0.2 µSv/hr and within 11 days in the case of 2.0 µSv/hr. When a time constant of 10 seconds was used at the dose rate of 0.2 µSv/hr, the estimated survey meter output error was 5%. Evaluation of the effect of individual differences in the location of the thyroid gland confirmed that the measured value would decrease by approximately 6% for a height difference of ±1 cm and increase by approximately 65% for a depth of 1 cm. Conclusion: In the event of a nuclear disaster, simple measurements carried out using a NaI(Tl) scintillation survey meter remain effective for assessing ¹³¹I intake. However, it should be noted that the presence of short-half-life radioactive materials on the body surface affects the detection limit.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.151-158
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• 2011

Forty nine accessions of the Sorghum bicolor (L) Moench collected from different agronomical zone of Gangwondo province, Korea were characterized morphologically on field trial. Plant length, stem diameter, tiller number, ear type, ear length, ear width, leaves length, leaves width and leaf color differed significantly in the cultivated accessions. Out of forty nine test accessions, six accessions (12.2%) showed comparatively taller height, measuring more than 300 cm, while, other ten test accessions (20.4%) were measured from 200~300 cm. There were no significant differences in the diameter of stem in the collected test accessions (2~3 cm). Of the total test accession, seven accessions showed leaf length of over 70 cm, and twenty two test accession revealed leaf length between 60-70 cm. Forty nine of the collected test accessions showed narrow and short leaves with white mid vain. These results provided additional information for the breeding programs and conservation of Sorghum bicolor as a bio-energy crop.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.168-172
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• 2008

A new peanut variety "Charmpyeong" (Arachis hypogaea ssp. hypogaea L.) was developed at the Yeongnam Agricultural Research Institute, NICS, in Milyang in 2007. It was developed from the cross between the high-yielding cultivar "Shindaekwang" and the very short stem cultivar "ICGV94216". This Virginia plant typed "Charmpyeong" has 33 cm stem height and 18 branch number Each pod with ellipse-shaped large kernel has two grains with brown testa and 100 seed weight was 88 g in the regional yield trials (RYT). This variety also showed more resistant to web blotch compared with check one. Especially it has resistance to lodging until harvesting owing to short stem. In the regional yield trials "Charmpyeong" was outyielded than check variety by 13% with 4.35 MT/ha for grain.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.179-185
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• 2005

The effects of $CO_2$ enrichment on growth of rice (Oryza sativa L.) were examined. The plants were grown in growth chambers with a 12-h photoperiod and a day/night temperature of $28/21^{\circ}C$ of the seedling stage and $30/23^{\circ}C$ after the panicle initiation stage. The plants were exposed to two elevated $CO_2$ of 500, 700 ppm and ambient levels (350 ppm). At early growth stage of three varieties (IIpumbyeo, Chucheongbyeo, Hwaseongbyeo), the elevated $CO_2$ increased plant height, tiller, leaf area and dry weight. The photosynthetic rate was decreased at 24 days after treatment (DAT) compared to 11 DAT. The elevated $CO_2$ increased plant height and dry weight at panicle initiation stage (PIS) and heading stage (HS) of three varieties (IIpumbyeo, Chucheongbyeo, Hwaseongbyeo). The photosynthetic rate, stomatal conductance, evapotranspiration rate were decreased at the long days of treatment than that of short days. At entire stages, the elevated $CO_2$ increased the water use efficiency of rice plant because evapotranspiration rate was lowered at the elevated $CO_2$ than ambient levels.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.87-96
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• 2009

Pinus thunbergii plantations in Pohang-si, Gyeongsangbuk-do, Korea, are of low ecological quality, with arrested succession and a high proportion of ruderal species. To improve the quality of the habitat, we created canopy gaps ($\sim42\;m^2$) and monitored changes in abiotic (light availability, canopy openness) and biotic (survival and growth of seedlings and understory communities) variables in 2007 and 2008 in plots that had received one of five types of treatment: cutting of canopy trees and removal of the understory (CU), cutting of canopy trees only (C), girdling of canopy trees and removal of the understory (GU), girdling of canopy trees (G) or control. Each treatment was applied to three replicate plots. Abiotic variables did not significantly differ among treatments. Survival rates of target species were slightly lower in the CU, G and control conditions. Based on logistic regression analysis, the only significant growth factor affecting survival was height growth. Positive effects of seedling height and leaf area growth on survival were also detected, but did not reach statistical significance. In treatment G, gradual improvement of overstory conditions and mitigation of competition by limitation of disturbance to the understory community were likely to have promoted seedling growth. There were no significant effects of gap treatments on changes in species abundance (cover and richness) and composition of understory between the study years. This result implies that the small gaps created in our study may be below the threshold size to affect understory growth. However, the results of this study are based on a short-term investigation of only two years. Long-term research is strongly recommended to clarify the effects of gap treatment on plant communities in afforested areas.

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.71-75
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• 1981

The percentage of lesion height vs. plant height was higher in Yushin than Jinheung within the same nitrogen level. The infection occurred at the same level of waterline and the symptoms developed with the same speed for two varieties, but the damage was greater in Yushin as the symptoms reached faster to the top due to the short length of the 1st and 2nd internodes from the top.