• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.340-346
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• 2000

This experiment was conducted to investigate the effect of nitrogen fertilization in job's tears (Coix lachryma-jobi L.) on the growth characteristics, grain yield, nitrogen accumulation, and chemical property of soil after harvest. Heading and budding stages were shorter than control but growth periods was increased because of the increase of ripening periods according to the increase of nitrogen fertilizer applications. Number of main culm node and culm diameter was similar but culm length and tiller number per plant were better according to the increment of nitrogen fertilizer applications than control but the decrease of grain yield was attributed to the fact that damage by corn borer was 30% in $240kg\;ha^{-1}$ of nitrogen treatment. Some of yield components was better according to the increment of nitrogen fertilizer applications but grain number per plant of $160kg\;ha^{-1}$ of nitrogen treatment was greater. So grain yield was the highest ($3,410kg\;ha^{-1}$) at the $160kg\;ha^{-1}$ of nitrogen fertilization. Nitrogen use efficiency decreased according to the increase of nitrogen fertilization. Total nitrogen of soil after experiment in 0, $80kg\;ha^{-1}$ of nitrogen treatments was lower and in 160, $240kg\;ha^{-1}$ of nitrogen treatments was higher than that before the experiment.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.71-77
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• 2001

Experiments were conducted to evaluate quality and vase life of cut rose 'Rote Rose' cultivated in soil or hydroponically in rockwool. Rose flower stems harvested in commercial greenhouses in Kimhae on May 27 and June 14, 1998 were transported for about two hours to a laboratory and recut in water to an uniform stem length of 45cm. The rose flowers harvested on the same day were displayed at a density of $10cm{\times}10cm$ and were subjected to the same environmental conditions in a growth chamber. The stems were put in four different preservative solutions, 0.5% Chrysal RVB, BS (2% sucrose+200ppm 8HQS+0.3% Chrysal RVB), Sonk1 (BS+0.1mM ethionine), and double distilled $H_2O$. Flower stems harvested on May 27 were displayed at $18{\pm}1^{\circ}C$, RH 60-70%, and light intensity of 220lux provided by fluorescent lamps for $16h{\cdot}d^{-1}$. Flower stems harvested on June 14 were displayed at $25{\pm}1^{\circ}C$, RH 70-80%, and light intensity of 220lux provided by fluorescent lamps for $16h{\cdot}d^{-1}$. Fresh weight and flower diameter were affected by cultivation method, and were greater in hydroponically-grown roses than in soil-grown roses. Among the preservative solutions, BS and Sonk1 were superior to Chrysal RVB in terms of prolonging vase life. Vase life extension in Chrysal RVB, BS and Sonk1 over the control was about one day in both display temperatures. At $18^{\circ}C$ vase life was maintained for three to four additional days as compared to that at $25^{\circ}C$.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.300-308
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• 2001

Objectives : Anterior cervical discectomy and interbody fusion has become a well-accepted surgical treatment of degenerative cervical diseases. Implatable cages have a stabilizing effect without plates and no need for autogenous bone graft. The authors evaluates the effect of implatable titanium cage(RABEA) on the clinical and radiological outcomes. Methods : 34 patients with symptomatic cervical degenerative diseases due to one level disc pathology were underwent anterior cervical discectomy and interbody fusion with titanium cages(RABEA) which were not filled with cancallous bone grafts from January 1999 to May 2001. Patients with osteoporosis and older than 65 years were not included. Among them, 15 patients could be followed-up for at least 1 year. The authors retrospectively reviewed the charts and radiographic data. Mean follow-up period was $1.3{\pm}0.2years$. Results : Clinical results according to the Odom's criteria was exellent and good in 14(93%) patients. One patient with fair result showed complete loss of the disc space height due to settlement of the cage. Preoperatively, the mean height of the disc space(${\pm}$standard deviation) was $3.42{\pm}1.10mm$(range 2.0-5.5mm), and at 1 day postoperatively it was $7.88{\pm}0.90mm$(range 6.50-9.0). The mean height of the disc space after 1 year was $6.50{\pm}1.38mm$(range 3.0-8.0). The restoration of the height was statistically significant(p<0.05). The mean height after 1 year was $82.7{\pm}15.9%$ of the height at 1 day postoperatively. Preoperatively the mean value of the cervical lodortic angle was $21.8{\pm}11.8^{\circ}$ and 1 year postopertively, it was $24.5{\pm}8.3^{\circ}$, which was statistically not significant. All patients showed no abnormal movements on flexion and extension lateral film after 6 months. Conclusion : Implantable titanium cages appear safe and effective in selected patients, and their use helps to avoid complications associated with bone graft harvest. Subsidence of the cage seems to be a potential risk factor for recurrence of the symptoms. For long-term results, a longer follow-up is required.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.421-430
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• 2022

Crop load management in apple trees is important for achieving optimum productivity and crop value. Hence, we investigated the influence of different crop loads on the fruit quality, mineral content, and yield of the 'RubyS' apple variety. After 4 weeks of full bloom, the crop load was adjusted by hand thinning to different (5, 10, and 15 fruits·cm^-2) trunk cross-sectional areas (TCSA), representing low, medium, and high crop loads. The low crop load increased the fruit size and weight, the development of the red-blushed area, and the peel color a^* at harvest; however, it reduced the total number of fruits·tree^-1 and yield compared with that of the other crop loads. The medium crop load improved the fruit weight, flesh firmness, and soluble solids content and reduced the fruits·tree^-1 but did not affect the fruit size and yield. However, there were no significant differences in the titratable acidity and starch index among the crop loads. The fruit mineral content (phosphorus and potassium) was higher in the low and medium crop loads compared to the high crop load. However, the nitrogen, calcium, and magnesium contents in the fruits were not affected by the crop loads. Overall, this study suggests that a low crop load improves the fruit size and weight, but its effect on the quality and fruit mineral content is similar to that of a medium crop load. Therefore, the optimum crop load level for the 'RubyS' apple trees was approximately 10 fruits·cm^-2 TCSA.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.295-303
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• 1999

An experiment was conducted to evaluate the possibility of using basic oxygen furnace (BOF) slag as a soil conditioner in rice paddy field. In 1997, rice (Oryza sativa B. cv. Dongjinbyeo) crop was cultivated under different application rates of BOF slag at three different places, Inandong Sunchon city, Youjunglee Bosung province, and Nampyung Najoo city. In each paddy field, five treatments, four application rate of BOF slag (0, 4, 8, $12Mg\;ha^{-1}$) and one application rate of lime ($2Mg\;ha^{-1}$) were tried with three replications. Plant height, number of tillers per hill, leaf area per hill, leaf dry weight, calm dry weight or shoot dry weight per hill were measured five times at the interval of seven days. Chemical contents of rice plants and soil were also measured at the same sampling date Yield were estimated by harvesting $6.6m^2$ per experimental unit and yield components were measured by sampling 10 plants per experimental unit at the harvest date. Application of BOF slag hardly affected contents of soil organic matter, available phosphate and potassium in soil. Soil pH and contents of Ca, Mg, Fe and $SiO_2$ enhanced as BOF slag rate increased. Enhancement of soil pH by ROF slag treatment appeared to be closely related with increase in soil Ca content. Application tate of $2Mg\;ha^{-1}$ of lime showed almost the same effect, in increase of soil Ca content as application rate of $4{\sim}8Mg\;ha^{-1}$ of BOF slag, Fe content in soil decreased sharply as time passed after slag treatment and stabilized more or less at the later sampling date. Contents of inorganic matter in plant such as total nitrogen, phosphate, potassium and Mg were not affected by BOF slag treatment. However, contents of Ca, Fe, and $SiO_2$ in plants increased as slag rate became higher. The growth of rice plants with BOF slag treatment was more or less slower but continued persistently up to the later growth stage, so that growth of plants with BOF slag treatment was almost the same nr even greater than that of control or lime treatment. However, BOF slag rate of $12Mg\;ha^{-1}$ seemed to be too high because all the measurements of plant, growth at this rate showed lower values than those of other treatments at all the sampling dates. Treatments of BOF slag $4Mg\;ha^{-1}$ or $8Mg\;ha^{-1}$ showed higher rough rice yield than other treatments, so that the optimum BOF slag ratein rice paddy field seemed to be in the rage of $4{\sim}8Mg\;ha^{-1}$.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.1
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• pp.33-38
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• 2011

This experiment was conducted to compare the dry matter yield and forage quality according to the seed mixture of annual legumes and Italian ryegrass (Lolium multiflorum, IRG) on paddy field at the experimental field of Jeollanam-Do Agricultural Research and Extension Services from 2007 to 2008. The five treatments used in this experiment were IRG single (cv. Kowinearly), IRG+Chinese milk vetch mixture, IRG + Crimson clover (cv. Linkarus) mixture, IRG + Austrian winter pea (Pisum sativum subsp. arvense cv. forage Pea) mixture and IRG + Hairy vetch (Vicia villosa. cv. Oregon Common) mixture. And the mixing ratio of Italian ryegrass + annual legumes were 70 : 30 as based mono seed rate. The dry matter (DM) percentage at harvest was 23.6~26.8%. The DM percentage among IRG single and mixture treatments were similar. The yields of fresh and CP were high in IRG + Forage pea mixtures as a 40,100 kg and 625 kg per ha, respectively (p<0.05). The yields of dry matter were high in IRG + Forage pea and IRG + hairy vetch pea mixtures as a 9,470 kg and 9,500 kg per ha, respectively (p<0.05). But the forage quality did not show difference between Italian ryegrass mono-culture and annual legumes mixture. The Av. $P_2O_5$ in IRG+Forage pea mixture was 78 mg/kg and concentration of K were 0.52~0.88. In conclusion, the mixture of IRG and Forage pea, dry matter yield, protein yield increased, and was effective in enhancing the stability of cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.493-497
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• 2000

An experiment was conducted to evaluate the possibility of using basic oxygen furnace (BOF) slag as soil conditioner in soybean upland field. In 1997, soybean (Glycine max L. cv. Eunha) crop was cultivated under different application rates of BOF slag at an experimental field of Chonnam Rural Development Administration in Nampyung, Najoo city. Five treatments, four application rates of BOF slag (0, 4, 8, $12Mg\;ha^{-1}$) and one application rate of lime ($2Mg\;ha^{-1}$) were tried with three replications. Plant height and shoot dry weight per plant were measured five times during the growth period. Chemical contents of soybean plant tissues and soil were also measured at the same sampling date. Yield were estimated by harvesting $6.6m^2$ per experimental unit and yield components were measured by sampling 10 plants per experimental unit at the harvest date. In upland soil, application of BOF slag rarely affected contents of total nitrogen, organic matter, available phosphate and potassium in soil. Soil pH, and contents of Ca and Fe in soil became higher as BOF slag rate increased. Enhancement of soil pH by application of BOF slag appeared to be closely related with increase in soil Ca content. Application rate of $2Mg\;ha^{-1}$ of lime showed almost the same effect in increase of soil Ca content as application rate of $4{\sim}8Mg\;ha^{-1}$ of BOF slag. Slag treatment hardly affected the contents of total nitrogen, $P_2O_5$, CaO, $K_2O$ and MgO in the shoot of soybean plants. Soybean plants under treatments of BOF salg showed better growth from the earlier growth stage compared with those of control treatment, and at the later growth stage, their growth was even superior to that of lime treatment. BOF slag rate of $8Mg\;ha^{-1}$ showed the highest soybean yield with $1,232kg\;ha^{-1}$. which was $330kg\;ha^{-1}$ or 37% higher than the yield of control with $902kg\;ha^{-1}$, As a result, BOF slag appeared to be useful material as a soil conditioner as well as nurient source for Ca and Fe in upland soybean fields, and its optimal rate for higher yield seemed to be around $8Mg\;ha^{-1}$.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.387-393
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• 2012

In order to improve storability of subtropical yam produced in South Korea, the major pathogens found during the storage were isolated and identified of the pathogenicity, and rot inhibition effect was studied based on the curing treatment condition. Penicillium sclerotigenum and Penicillium polonicum were identified as major pathogens causing rot in subtropical yam during storage, and P. sclerotigenum had stronger pathogenicity. Only the cut surface which has been made during a harvest and has been made smooth before curing generated a normal callus layer. The cut surface of tuberous root was cured in 95% of relativity humidity for three days at $23^{\circ}C$, and cured at $28^{\circ}C$ and $33^{\circ}C$. The observation of callus layer showed that the $23^{\circ}C$ treatment group had similar color saturation between tuberous root and pellicle, while the groups treated above $28^{\circ}C$ showed clear distinction. The generation rate of callus 0.5mm or bigger was 93 percent at $28^{\circ}C$ treatment, 96% at $33^{\circ}C$ treatment, but was 52% at $23^{\circ}C$ treatment. The conventional curing treatment group that used wind or sunlight at room temperature created little callus layer. The infection rate of pathogens according to the relative humidity inside the storage room was low at 40% and 60% of humidity, and the curing treatment period did not make a difference. When the humidity inside the storage room was 80%, all treatment groups rapidly increased the fungal pathogens. The rotten rate of each treatment was studied after 180 days during which the storage temperature was maintained at $16^{\circ}C$ and relative humidity 60%. While the rotten rate of tuberous root that has been cut in conventional curing treatment based on solar and wind was 43%, the one cured at over $28^{\circ}C$ and created the callus layer was less than 18%. While even a healthy tuberous root showed 25% of rotten rate in the traditional treatment group, the one cured at over $28^{\circ}C$ was less than 10%. The weight loss was 1-6% lower in the forced treatment group than in the conventional treatment group.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.534-542
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• 2012

This study was conducted to investigate the effect of 1-methylcyclopropene (1-MCP) on fruit quality and incidence of physiological disorders for keeping freshness during marketing period in Asian pear (Pyrus pyrifolia Nakai) 'Wonhwang' and 'Whasan'. Fruits were treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP for 12 hours at $25^{\circ}C$, at two or three stages of ripeness as determined by days after full bloom (DAFB). Fruits were harvested at 130 and 140 DAFB in early season cultivar 'Wonhwang' and 135, 145, and 150 DAFB in mid-season cultivar 'Whasan', respectively. Fruits were stored at $25^{\circ}C$ for 21 days and measured the flesh firmness, weight loss, soluble solids, acidity, ethylene, respiration and severity of physiological disorders at week interval. 1-MCP treatment to 'Wonhwang' pears harvested at 130 and 140 DAFB effectively delayed firmness loss during storage at $25^{\circ}C$. Untreated fruits of 'Wonhwang' pears harvested at 130 DAFB showed 32.3 and 10.1N of firmness after 14 and 21 days of shelf-life at $25^{\circ}C$, respectively, while those of the 1-MCP treated fruits showed 39.4 and 33.1N during same period. In the fruits harvested at 140 DAFB, the firmness of untreated fruit was lowered to 14.8 and 6.6N after 14 and 21 days, respectively, but those of 1-MCP treated fruit were 35.0 and 33.3N, respectively. Whereas, 1-MCP treatment delayed firmness loss only in the fruit harvested late (150 DAFB) in 'Whasan' pears. Higher soluble solids content and acidity during extended shelf-life were apparent in 1-MCP treated 'Wonhwang' pears, while those of 'Whasan' pears were little changed. 'Wonhwang' pears showed a relatively high ethylene production (maximum $0.58{\mu}l{\cdot}L^{-1}$) in the fruits harvested late than early harvested one. 'Whasan' pears showed little amount of ethylene production regardless of extended shelf-life. 1-MCP treatment to 'Wonhwang' pears decreased respiration rate following shelf-life, 42 and 50% reduction were observed at 14 days of shelf-life when compared with those of untreated ones harvested at 130 and 140 DAFB, respectively. No reduction of respiration rate by the treatment of 1-MCP was detected in 'Whasan' pears which showed considerably low respiration rate compared with 'Wonhwang' pears. Harvest time influenced the level of physiological disorders together with extension of shelf-life in both the cultivars. 1-MCP treatment completely blocked the incidence of internal browning of 'Wonhwang' pears harvested at 130 DAFB, and reduced the incidences of pithiness and core browning, while it promoted the flesh spot decay disorder regardless of harvest time. 1-MCP treatment was of little benefit for the prevention of physiological disorders in 'Whasan' pears compared with those of 'Wonhwang'.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.1
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• pp.1-15
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• 2014

The cultivation situation of Korean wheat of 175 farmers in nationwide for two years, 2010/2011 and 2011/2012, was analyzed to obtain basic data for extension cultivated area and enhancing the self-sufficiency ratio of Korean wheat. Compared to the mean temperature and precipitation in the normal year, the mean temperature was lower before the heading stage and higher amount of precipitation after the heading stage in 2010/2011 and higher the mean temperature and lower amount of precipitation after the heading stage in 2011/2012. Average cultivation career and area were 7.7years and 2.4~3.3ha, Keumkang cv. was mainly cultivated for two years and Jokyung and Baekjoong cvs. were increased cultivation areas in southern part of Korea, Gyeongsangnam-do, Jeolllanambuk-do and Kwangju metropolitan city, including in 2011/2012. Most farmers (144) sown wheat seeds from late October to the beginning November with broadcasting method and the other famers were sown using the drill method. Average amount for basal fertilizer was 29.7 kg/10a with complex fertilizer mixed for wheat and barley cultivation, which was higher amount compared to recommended rate of fertilizer amount by rural development administration. Top dressing using nitrogen fertilizer was applied from in the late February to the beginning March. Heading date was the beginning May in 2011 and the late April in 2012, which the mean temperature from regeneration stage to tillering stage in 2011 was higher than that of 2012. Most farmers harvested wheat in mid-June and Pre-harvest sprouting and Fusarium head blight were occurred in 2011 due to the high amount precipitation during grain filling period.