• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.173-178
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• 2003

To determine the optimum $\textrm{P}_2\textrm{O}_5$ rate for dry matter production of Achyranthes japonica Nakai a medicinal plant, in Jeju island, plants were grown in 2001 under ten fertilizer treatments comprising of two N (90, and 180kg/ha) and five $\textrm{P}_2\textrm{O}_5$ (0, 100, 200, 300, and 400 kg/ha) levels. Plant height leaf length and width, stem diameter, and main root length and diameter were not significantly affected by $\textrm{P}_2\textrm{O}_5$ rate while $\textrm{P}_2\textrm{O}_5$ fertilization of 100 kg/ha increased the number of branches, spikes, and roots per hill by 18,38 and 43%, respectively, compared with the unfertilized $\textrm{P}_2\textrm{O}_5$ treatment and decreased with further increases in $\textrm{P}_2\textrm{O}_5$ rate. The number of roots per hill was greatest with the application of 200kg $\textrm{P}_2\textrm{O}_5$. The highest utricle dry matter yield (2.92 t/ha) was obtained with the application of 100kg $\textrm{P}_2\textrm{O}_5$. However, as $\textrm{P}_2\textrm{O}_5$ rate increased from 0 to 100 and 200kg/ha, root dry matter yield increased from 2.36 to 3.55, and 3.80 t/ha, and then decreased to 3.14, and 2.86 t/ha at 300, and 400kg $\textrm{P}_2\textrm{O}_5$ rates, respectively. As $\textrm{P}_2\textrm{O}_5$ rate increased from 100 to 400 kg/ha, $\textrm{P}_2\textrm{O}_5$ recovery in aboveground parts decreased from 34.1 to 7.1%.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.1-15
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• 2015

To mitigate the impacts of climate change on agricultural ecosystems, development of agricultural management for enhanced soil carbon sequestration is required. In this study, the effects of fertilizer types (chemical fertilizer and manure compost), cropping systems, and crop residue management on SOC(Soil Organic Carbon) sequestration were investigated. Summer corn and winter barley were cultivated on experimental plots under natural rainfall conditions for two years with chemical fertilizer and manure compost. Soil samples were collected conducted and analyzed for SOC for soil. To estimate long-term variation patterns of SOC, DNDC was run with the experimental data and the weather input parameters from 1981 to 2010. DNDC simulation demonstrated SOC reduction by chemical fertilizer treatment unless plant residues are returned; whereas compost treatments increased SOC under the same conditions and SOC increment was proportional to compost application rate. In addition, SOC further increased under corn-barley cropping system over single corn cropping due to more compost application. Regardless of nutrient input type, residue return increased SOC; however, the magnitude of SOC increase by residue return was lower than by compost application.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.22-27
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• 2006

The aim of this study was to establish the maximum residue limits(MRLs) of fenhexamid, azoxystrobin and cyprodinil pesticides in ginseng products. The pesticides were applied to the cultivation field of ginseng, and they were harvested and processed to make dried ginseng and ginseng extract. The reduction factors of residual pesticides were calculated by determination of the pesticides in each processing stage of ginseng. Reduction factor (dry basis) of pesticides (azoxystrobin, fenhexamid, cyprodinil) were 0.73, 0.96 and 0.24 for dried ginseng and 3.23, 5.74 and 1.20 for ginseng extract. All the residual pesticides were reduced by drying or processing of ginseng, however, fenhexamid did not.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.8-14
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• 1996

Use of phosphate coated urea to decrease ammonia volatilization from directly seeded paddy under dryland condition at early stage was tested. Effect on urea hydrolysis was investigated through laboratory study comparing with use of thiourea, a urease inhibitor, under different water content. A field measurement of volitilized ammonia with phosphate-glycerol ammonia absorber was conducted for surface treated urea, phosphate coated urea, phosphate coated slow-release fertilizer and organic fertilizer. Through laboratory study, hydrolysis rate of phosphate coated urea at three days after treatment was lower than that of urea, however, the rate after one week was same. Thiourea addition retarted urea hydrolysis. By field measurement, ammonia volatilization was effectively reduced by use of phosphate coated urea.

• Korean journal of applied entomology
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• v.9 no.2
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• pp.91-94
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• 1970

Tobacco wild fire caused by Pseudomonas tabaci(Wolf et Foster) Stevens is one of the most important diseases on tobacco plant in Korea. The objectives of the study were to investigate: 1) the relationships between environmental conditions and the disease development, 2) the effect of chemical spray and soil sterilization on the disease development, and 3) the proper date for chemical sprays during the growing season. The appearance of wild fire on tobacco plant was somewhat proportional to temperature and moisture in atmosphere. The first occurrence of the disease was in late part of June when the temperature was $18\;to\;20^{\circ}C$. with $65\;to\;70^{\circ}C$ of relative humidity. The disease was, then, gradually increased during early part of July with the temperature of $22\;to\;26^{\circ}C$. and $85\;to\;86^{\circ}C$ of. relative humidity. The rapid development of the disease occurred after heavy rain or storm during July. Two to three times of Phytomycin sprays(1:300-350) during the epidemic season reduced $28.3\%$ of disease damage when compared with control plot. Soil sterilization with chloropicrin. 10 liter/10a, Prior to transplanting of seedlings reduced not only wild fro damage but also the other tobacco diseases on field. The study showed that the damage caused by tobacco wild fro could be reduced with the use of early varieties and/or 2 or 3 times of Phytomycin sprays during early part of June, and soil sterilization with chloropicrin prior to transplanting.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.69-74
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• 2008

This study aims to establish the efficient soybean transformation system and develop soybean [Glycine max (L.) Merill] transformants using cotyledonary node explants. The cotyledonary node of soybean were co-cultivated with Agrobacterium tumefaciens strains (KYRT1, EHA105). These strains contain the binary vector pCAMBIA3301 which carries a herbicide-resistant far gene. Korean cultivars (Danbaekkong, Eunhakong) and foreign cultivars (Jack, Peking) were the most efficient in regenerating cotyledonary node. Therefore, they were chosen for the transformation. Results showed that the T-DNA transfer reached up to 60% and transformation efficiency reached up to 3% in the cotyledonary node explants from Jack cultivar, co-cultivated with EHA105 strain. Histochemical GUS evaluation showed that 12 individual lines, transformed with the 현 gene, have positive response. The transformed soybeans have been confirmed in the $T_0$ generation through phenotypic assay using herbicide $Basta^{(R)}$ and Southern blot analysis.

• Research in Plant Disease
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• v.13 no.3
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• pp.211-215
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• 2007

Since 2003, anthracnose symptoms on Eucalyptus globulus were observed in farmer's field at Jisepo, Ilwoon-myon, Geoje city, Gyeongnam province, Korea. Typical symptoms of dark brown to black spot appeared on the leaves, twigs, and stems. Infected young trees were wilted, blighted and died eventually. The pathogen isolated from the typical symptom formed gray to dark gray colony on potato dextrose agar and showed optimum growth at $30^{\circ}C$. Conidia were single celled, colorless, cylindrical with obtuse ends, and $9{\sim}22{\times}3{\sim}6{\mu}m$ in size. Appressoria were dark brown, ovate to obovate, and $6{\sim}18{\times}4{\sim}10{\mu}m$ in size. Perithecia were black and globose in shape and $76{\times}274{\mu}m$ in size. Asci were clavate to cylindrical in shape and $42{\sim}76{\times}8{\sim}12{\mu}m$ in size. Ascospores were cylindrical, fusiform, slightly curved at the center, and $10{\sim}23{\times}4{\sim}6{\mu}m$ in size. On the basis of mycological characteristics and pathogenicity test on E. globulus, the pathogen was identified as Glomerella cingulata. This is the first report of the anthracnose on E, globulus caused by G. cingulata in Korea.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.453-465
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• 2018

Radish (Raphanus sativus L.) is a species of the Brassicaceae family and an important root vegetable crop, produced worldwide. A total of 82 radish accessions with various morphological and physiological characteristics analyzed for total sugars content. These accessions includes five subspecies and classified as wild, wild-relative, traditional and improved cultivar. The four sugars, glucose, fructose, sucrose and maltose, showed various contents in 82 accessions. Total sugar content ranged from 5.64 to 46.68 mg/g and showed average 25.33 mg/g. Total sugar content was not statistically significant among the five subspecies, but individual sugar ratio varied. The wild, wild-relatives and traditional cultivars were not significantly among average total sugars content compared with improved cultivars. On the other hand, the wild and traditional cultivars were showed high ratio of individual sugars. These results could be valuable information for the development of new radish cultivars and regulation of sugars biosynthesis in radish.

• Research in Plant Disease
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• v.16 no.1
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• pp.86-89
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• 2010

Brown leaf spot caused by Phyllosticta cruenta from 2007 to 2009 occurred severely in an herbs exhibition on Doonggulle (Polygonatum odoratum) at Gangju pond in Jeongchon-myon, Jinju city, Gyeongnam province, Korea. The typical symptoms of this disease were appeared on the brown leaf spot of leaves. Lesions on the leaves were appeared elliptical or irregular with 2~8 mm in size. Infected leaves were wilted, blighted and eventually died. Pycnidiospores and pycnidia of the fungus were abundantly formed on PDA. The optimum temperature for mycelial growth was $20{\sim}{25^{\circ}C}$. Pycnidiospores were not readily formed on PDA, colorless in color, globose~subglobose in shape, $10{\sim}18{\times}5{\sim}12{\mu}m$ in size and appendage hanged $4{\sim}15{\mu}m$ in size. Pycnidia were globose~subglobose in shape, dark brown in color and $60{\sim}162{\times}70{\sim}174{\mu}m$ in size. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Phyllosticta cruenta (Kunze: Fries) Kickx. This is the first report on the brown leaf spot of Doonggulle caused by P. cruenta in Korea.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.383-390
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• 2016

To determine whether FT-IR spectral analysis based on multivariate analysis could be used to discriminate Chinese cabbage breeding line at metabolic level, whole cell extracts of nine different breeding lines (three paternal, three maternal and three $F_1$ lines) were subjected to Fourier transform infrared spectroscopy (FT-IR). FT-IR spectral data of Chinese cabbage plants were analyzed by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA), and hierarchical clustering analysis (HCA). The hierarchical dendrograms based on PLS-DA from two of three cross combinations showed that paternal, maternal, and their progeny $F_1$ lines samples were perfectly separated into three branches in breeding line dependent manner. However, a cross combination failed to fully discriminate them into three branches. Thus, hierarchical dendrograms based on PLS-DA of FT-IR spectral data of Chinese cabbage breeding lines could be used to represent the most probable chemotaxonomical relationship among maternal, paternal, and $F_1$ plants. Furthermore, these metabolic discrimination systems could be applied for rapid selection and classification of useful Chinese cabbage cultivars.