• The Korean Journal of Mycology
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• v.31 no.1
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• pp.44-49
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• 2003

Several microbial biocontrol products (Greenbiotech Co., Paju, Korea), Green-all T (Trichoderma harzianum), Green-all S(Bacillus sp.) and Green-all G (Streptomyces sp.) were supplemented with organic amendments such as sawdusts and rice hulls to study on efficacy of biological control of seeding damping-off of cucumber caused by Pythium ultimum. Sawdusts amended into potato dextrose agar alone could inhibit in vitro mycelial growth of P. ultimum. All there microbial products of Green-all T, Green-all G and Green-all S significantly reduced seeding damping-off (LSD, P=0.05). However, several amendments such as sawdusts and rice hulls into Green-all T and Green-all S products did not increase efficacy of biological control compared to non-amended treatment. In contrast, supplements of aminodoctor containing several amino acids (Greenbiotech Co., Korea) into Green-all G product significantly increased efficacy of biological control of seeding damping-off, resulting in from 42% to 2% disease incidence in relation to seedling emergence (LSD, P=0.05). Also, amendment of sawdusts into Tricoderma product significantly increased efficacy of biological control as disease index of 5.0 compared to non-amended control of 56.0 in Green-all T product alone. This indicates that organic amendments could increase efficacy of biological control of cucumber seedling damping-off.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.168-173
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• 2011

This study was carried out to optimize the embryogenic callus induction and plant regeneration from mature seeds of Sorghum bicolor. The effect of growth regulators was investigated on formation of embryogenic callus. The highest frequency of embryogenic callus was observed when the mature seeds were cultured on B5 medium supplemented with 2 mg/L 2,4-Dichlorophenoxyacetic acid (2,4-D). The highest frequency of plant regeneration from embryogenic callus was observed on MS medium with 0.5 $mg\;l^{-1}$ 6-benzyl amino purine (BAP) and 0.25 $mg\;l^{-1}$ indole-3-butyric acid (IBA) to optimize the shoot regeneration. High concentration of BAP (1 $mg\;l^{-1}$) supplemented with IBA (0.25 $mg\;l^{-1}$) was effective combination for shoot multiplication. MS medium supplemented with 1 $mg\;l^{-1}$ IBA was found to be the most effective for inducing roots. Normal rooted plantlets were transferred to the greenhouse for hardening with over 90% survival rate. Hence, this reproducible protocol could be useful for mass propagation and genetic transformation of S. bicolor.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.128-135
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• 2016

This study examined radiation damage and the optimal gamma-ray dose for mutation breeding in oat (Avena sativa L. cv. Samhan). The seed germination rate decreased as the dose increased over 500 Gy. The median lethal dose (LD₅₀) was approximately 392 Gy. The median reduction dose (RD₅₀) for plant height, tiller number, root length, and flash weight was 411, 403, 394, and 411 Gy, respectively. The optimal dose of gamma irradiation for inducing oat mutation appears to be in the range 300-400 Gy. We performed the comet assay to observe nuclear DNA damage induced by gamma-ray irradiation. This assay showed a clear difference with gamma-ray treatments. DNA damage increased temporarily 7 days after treatment depending on the dose, while no significant difference was identified in response to 300 Gy 30 days after the gamma-ray treatments. The growth characteristics of the M₂ generation decreased as the dose increased over 400 Gy.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.157-161
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• 2010

Photosynthetic purple nonsulfur bacterial strains were isolated from the sediments collected from rice paddy fields and sludges of wastewater treatment plant, and their plant growth promoting capabilities were examined. Most well known phytohormones, auxin such as indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) and 5'-aminolevulinic acid (ALA) were detected by HPLC in the culture broth of these isolates. Among the isolated bacteria, Rhodopseudomonas faecalis D15 showed the highest production rate of 769.8 ${\mu}g$/mg protein of IAA, 1323 ${\mu}g$/mg protein of IBA and 7.4 mM/mg protein of ALA in the modified Biebl and Pfennig's medium. R. faecalis C9 showed the highest production rate of 20.82 ${\mu}g$/mg protein of gibberellin. In consequence, the root length and dry weight of the germinated tomato seedling treated with R. faecalis isolates were longer and heavier than those of uninoculated control after 15 days of incubation in the soil. Especially, the dry weight of germinated tomato seedling increased by 119.4% in C9-treated samples after 15 days. These purple nonsulfur bacteria may be utilized as environment-friendly biofertilizer in the agriculture.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.552-556
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• 1994

It was aimed to study the chemical characteristics and volatile compounds of juices extracted by press (PE) and centrifugal extractors (CE). Citrons cut up cross direction were used as samples in PE. Proportion ratio of peel, flesh, and seed of citron were 43.9, 39.4 and 16.7%, respectively. Yield of juice increased with weight to 120g of citron fruit. pH, brix, pulp, oily materials, amino nitrogen and yield of juice extracted by CE were higher than those of juice by PE. Acidity and transmittance of juice extracted by PE were higher than those of juice by CE. Free sugars of citron juice were consisted of fructose, glucose and sucrose. Free sugar contents of juice by CE were twice as much as those of PE. Major volatile compounds of total steam distillation matters of citron juice extracted by PE were dl-limonene, ${\gamma}-terpinene\;{\beta}-farnesene$, sabinene, linalool, ${\beta}-myrcene$ and terpinolene, while those by CE were dl-limonene, ${\gamma}-terpinene$, sabinene, ${\beta}-myrcene,\;{\alpha}-pinene$, linalool and terpinolene. dl-Limonene and ${\gamma}-terpinene$ consisted of $73{\sim}83%$ of total volatile compounds. dl-Limonene of juice by CE increased about 6% that of juice by PE. ${\beta}-Farnesene$ were observed trace in juice by CE but presented in 7% in juice by PE. The results would suggested that chemical characteristics and volatile compounds of citron juice seemed to depend on extraction methods.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.229-235
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• 2012

This study was conducted to investigate the climatic factors affecting bud phenology of Pinus densiflora provenances. Data were collected from Jungseon, Chungju and Jeju plantations which were parts of the 11 provenance trials established by Korea Forest Research Institute in 1996. The 36 provenances were included in this trial ($33^{\circ}30^{\prime}{\sim}38^{\circ}08^{\prime}$ in latitude and $126^{\circ}30^{\prime}{\sim}129^{\circ}20^{\prime}$ in longitude). The bud swelling date and bud burst date of the provenances were investigated from March to May in 2004 in two-day interval. The four geographic factors and fifteen climatic factors of the test sites and provenances were considered in this study. Canonical correlation analysis was conducted to examine the major factors affecting the bud phenology. Our results suggested that the major factors affecting the timing of bud swelling and burst are the differences in latitude, longitude, extremely low temperature (during December-February), extremely high temperature (during November-February) and annual mean growing days between test plantation and provenance. The provenances with lower winter temperature than that of plantation showed the faster bud swelling and bud burst. Based on these results, the implication on the seed transfer of P. densiflora was discussed.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.149-154
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• 2003

Potato blackleg disease caused by Erwinia carotovora subsp. atroseptica has been a serious problem in Korea. It was previously reported that four mixtures [streptomycin (9.3 ppm) + copper oxide (171.6 ppm)/copper hydroxide (146.3 ppm), streptomycin sulfate (7.0 ppm)+copper oxide (171.6ppm)/copper hydroxide (146.3 ppm)] were effective for the control of E. carotovora subsp. atroseptica. in in vitro test. Using those four mixtures and two antibiotics [streptomycin (81.4 ppm) and streptomycin sulfate (61.3 ppm)], the effectiveness of control for E. carotovora subsp. atroseptica. was conducted in the field. Two antibiotics showed over 60% of control efficacy under different soil conditions, while mixtures of two antibiotics with copper compounds did not show any control effects on the infected seed potato. Two mixtures [streptomycin (27.9 ppm)+copper hydroxide (438.9 ppm), streptomycin sulfate (21.0 ppm) + copper oxide (514.8 ppm)] were effective in the control of potato blackleg disease on the infected potato plants under different climate conditions.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.485-489
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• 2011

In previous reports, the treatment of Bacillus amyloliquefaciens strain EXTN-1 showed a broad diseasecontrolling spectrum to the plant diseases caused by viral, bacterial, and fungal pathogens as well as the promotion of plant growth. In mechanisms of EXTN-1, treatment of EXTN-1 increased oxidative burst in early stage and induced the expression of resistance genes, PR-1a, PDF1.2. Mechanism involved in induced systemic resistance by EXTN-1 was revealed as simultaneous activation of SA and JA or ethylene metabolic pathways. The purpose of this study was to determine whether B. amyloliquefaciens EXTN-1 has a similar effect on rice plant against Rice stripe tenuivirus (RSV) under greenhouse conditions. When rice seeds were soaked in B. amyloliquefaciens strain EXTN-1, rice plants showed significant systemic resistance against RSV as well as promoted growth. In the case of plant growth, in 30-day old plants treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 12.6%, 9.8%, and 16.0%, respectively confirming the effects of PGPR. When the induced systemic resistance to RSV was examined, in 20-day old plants were treated with B. amyloliquefaciens EXTN-1, the heights, weights, and lengths of roots increased by 8.4%, 10.9%, and 4.8%, respectively compared to the control. Induced systemic resistance was more prominent in susceptible cultivars - Chucheong and Ilpum compared to the resistant cultivar, Nakdong.

• Journal of Plant Biotechnology
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• v.32 no.2
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• pp.85-90
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• 2005

This study was conducted to investigated the major characteristics of genetically modified rice of 'Milyang 204' originated from Dongjinbyeo compared to a non-transgenic rice varieties Dongjinbyeo and Jun-ambyeo. Basta resistant transgenic rice lines carrying bar gene produced by the Yeongnam Agricultural Research Institute were evaluated for their agronomic characters. The transgenic Japonica rice of 'Milyang 204' showed inferior phenotypic traits compared to a non-transgenic rice variety Dongjinbyeo and Junambyeo. On the basis of UPOV (Union Internationale Pour la Protaection des Obtentions Vegetables) and NSMO(National Seed Management Office) the transgenic 'Milyang 204' showed difference in some traits out of some agronomic traits, such as leaf color, angle of flag leaf, number of spikelets, culm length, white core and white belly compared to the non-transgenic varieties rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.15-21
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• 1986

This study was conducted to research the industrial utilizaion of the maize germs separated in the manufacture of the cornstarch. The maize germs contained crude protein (25.3%) and crude fat (19.2%), with the 512 Kcal/100g of determined food energy values. It was found to have the valuable amounts of essential minerals, such as the content of calcium and phosphorus were low (53.0, 12.3mg%), while those of potassium (495.4mg%), magnesium (95.0mg%), zinc (48.3ppm) and manganese (45.2ppm) were plentiful. It was noted that the iodine value was 44.0, saponification value 292.3, acid value 1.5 and peroxide value about 3.3. The lipid fractions obtained by silicic acid column chromatography were mainly composed of neutral lipid, whereas, the contents of glycolipid and phospholipid were scarcely. The major fatty acids in total lipids were linoleic $(60{\sim}62.5%)$, oleic $(20{\sim}22.5%)$ and palmitic $(10{\sim}13.5%)$ acids. The content of the unsaturated fatty acids was more predominant than that of the saturated fatty acids. The content of the insoluble proteinous nitrogen (32.5%) was the most abundant. whereas, the contents of soluble proteinous nitrogen (12.7%) and peptide proteinous nitrogen (3.3%) were low. The major amino acids of the maized germs were glutamic, glycine, alanine and aspartic. It has been identified by the SDS-disc electrophoresis that the protein of maized germs had $5{\sim}6$ bands. Compared with standard substances, the molecular weight of the main protein was estimated to be $14,500{\sim}24,500$.