• Korean journal of applied entomology
• /
• v.17 no.2 s.35
• /
• pp.89-98
• /
• 1978

A study on the root-knot nematodes (Meloidogyne spp.) affecting economic crops in Korea was undertaken to know the distribution of the nemic fauna. Total 66 samples were taken from soil and root of 24 host plants at different localities in 4 provinces. Four Meloidogyne species such as Meloidogyne hapla, Meloidogyne arenaria, Meloidogyne incognita and Meloidogyne javanica were identified and some morphological characteristics were described. One of these, Meloidogyne javanica was reported newly in Korea from Horticultural Experimental Station, Suweon, Gyeong Gi on potato, Geomsadong, Daegu on chinese cabbage, Sangeogdong, Daegu, Gyeong Bug on violet and Choeumri, Namhae, Gyeong Nam on pumpkin. In Jae Ju province, Meloidogyne incognita was only found except the other three species. The most common and widely distributed Meloidogyne species in Korea is Meloidogyne hapla by $50\%$ in total, next Meloidogyne incognita $33.3\%$ Meloidogyne arenaria $10.6\%$ Meloidogyne javanica $6.0\%$ in turn, The root-knot nematodes infected the most severely in Jae Ju province and Gyeong Nam, Gyeong Bug and Gyeong Gi province in turn. Twenty four plants were attacked by root-knot nematodes among them important economic crops are soybean, peanut, potato, tomato, cucumber, carrot, pumpkin, wateremelon, edible burdock, pepper, eggplant, cabbage, lettuce and tobacco in Korea.

• Journal of Plant Biotechnology
• /
• v.38 no.1
• /
• pp.42-48
• /
• 2011

Chloroplast genetic engineering of higher plants offers several unique advantages compared with nuclear genome transformation, such as high levels of transgene expression, a lack of position effect due to site-specific transgene integration by homologous recombination, multigene engineering in a single transformation event and reducing risks of gene flow via pollen due to maternal inheritance. We established a reproducible chloroplast transformation system of potato using a tobacco specific plastid transformation vector, pCtVG (trnI-Prrn-aadA-mgfp-TpsbA-trnA). Stable transgene integration into chloroplast genomes and the homoplasmic state of the transgenome were confirmed by PCR and Southern blot analyses. Northern, immunoblot analysis, and GFP fluorescence imaging revealed high expression and accumulation of GFP in the plastids of potato leaves. This system would provide new opportunities for genetic improvement and mass production of value added foreign proteins in this crop.

• Korean journal of applied entomology
• /
• v.46 no.3
• /
• pp.401-408
• /
• 2007

The feeding behaviors of 2 biotypes (type B and Q) of tobacco whitefly, Bemisia tobaci, were monitored using EPG technique on tomato and pepper plants treated 3 insecticides for controlling whiteflies, for examples, acetamiprid, spinosad and thiamethoxam. After treatment of three insecticides with recommended concentrations to tomato and pepper plants, EPG waveforms were recorded during 6 hours. The characteristic patterns of feeding behaviors investigated were as follows; time consumed by withdrawal of proboscis, total non-penetration time, total stylet pathway pattern time and total phloem feeding time. There was somewhat difference among 3 insecticides tested. As a result of investigation of total duration showed the stylet pathway activity due to the reaction against all tested insecticides, the Q biotype showed fewer time than those from the B biotype. The B biotype showed more frequent stylet pathway activity patterns during whole recording time and a shorter phloem ingestion time than those from the Q biotype. In result of prior up (non-penetration) time representing the reaction against the insecticide treated, the time of B biotype was more faster than that of the Q biotype, so it was considered that the B biotype was more sensitive to the tested insecticides. Therefore, our results revealed a clear difference in feeding behaviour between the B and Q biotypes of B. tabaci. Also, it was investigated that B biotype was susceptible to the 3 insecticides.

• Korean Journal of Plant Resources
• /
• v.18 no.1
• /
• pp.15-21
• /
• 2005

Korean ginseng(Panax ginseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In transformation of ginseng with betain aldehyde dehydrogenase gene, compounds synthesized for controlling osmotic pressure such as proline, glycine, betaine, polyols and sugar were accumulated in cell for salt resistance in transgenic plants. 2 Agrobactgerium conjugants were acquired with bet A and bet B genes for solt resistant plants. A. tumefaciens MP90/pBetA and A. tumefaciens MP90/pBetB were recombined for increasing the tolerance to salt stress. To confirm the transformation of the binary vector, tobacco plant was transformed, and the transformant can grow on media containing high concentration of kanamycin. To identify NPT 11, BetA and BetB genes of the transformants, the band on the agarose was confirmed by PCR and RT-PCR techniques. The transformants of ginseng with bet A and bet B genes were acquired on the phytohormone free basic MS media containing only antibiotics and 1M mannitol used for selection of transgenic plant, but the transfomation efficiency for BetA and BetB was very low.

• Research in Plant Disease
• /
• v.24 no.4
• /
• pp.328-331
• /
• 2018

A severe disease with leaf spots and necrotic symptoms was observed in cucumber (Cucumis sativus L.) seedlings in April 2018 at a nursery in Kimjae, Korea (35o 47'09.8"N 127o 2'24.3"E). The infected plants initially showed spots on water-soaked cotyledons which, at later stages, enlarged and spread to the leaves, which the lesions becoming dry and chlorotic. The symptomatic samples were collected from cucumber and the isolates were cultured on LB agar. The representative bacterial strain selected for identification showed fluorescent on King's medium B, was potato rot-positive, levan and arginine dihydrolase-negative, oxidase-negative and tobacco hypersensitivity-positive in LOPAT group 2 as determined by LOPAT tests. A pathogenicity test was carried out on a 3-week-old cucumber. After 3 days of inoculation, leaf spots and necrotic symptoms appeared on the cucumber, similar to the originally infected plants. The infecting bacterial strain was identified as Pseudomonas viridiflava, by 16S rDNA sequence analysis. This is the first report of leaf spot diseases on cucumber caused by P. viridiflava.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.1
• /
• pp.7-13
• /
• 2001

Calli were induced from diploid and haploid tobacco after 4 weeks and maintained on MS medium with combination of 2.0 mg/L 2,4-D,0.1 mg/L BAP and 2.0 mg/L kinetin. Suspension cells were screened through 65 $\mu$m-nylon mesh and 100 $\mu$m-mesh, then they were smeared on selection medium combined with cadmium and PFP by using the low melting agarose of 0.8%. After 30days smeared cultures of the medium the cell was treated with 500 $\mu$M and 1000 $\mu$M to select the resistant cell line were selected. Plant regeneration was induced from the selected cell lines on medium with 0.5, 1.5, 2.0 mg/L BAP and on media with combination of auxin and BAP under 500 $\mu$M and 1000 $\mu$M cadmium. At this time, plant regeneration was achived on cadmium free medium. In case of haploid, occurred from the cell line which is selected in medium with cadmium and PFP. In case of diploid regeneration occurred is in the medium with cadmium alone. The plantlet regenerated from cadmium resistant calli grew well in cadmium 500 $\mu$M. Protein pattern of leaf, root, stem of regenerated plants was analyzed. The quantum was 6.5188 ug/mg.fr.wt in the leaf of plant, 5.3611 ug/mg.fr.wt in the stem, 3.0213 ug/mg.fr.wt in the root. On the other hand, 5.9652 ug/mg.fr.wt. in the leaf of control, 3.5974 ug/mg.fr.wt in the stem of the control, 4.3766 ug/mg.fr.wt. in the root of the control. The one dimension bends regenerated from cadmium resistant calli resistant to cadmium in leaf were 49 involving 198.7KD etc. Disappeared were 4 involving 160.5KD etc, The protein bends were combinized were 3 involving 83.4KD etc. The bends resistant to cadmium stress in stem were 41 involving 4.3KD etc. Disappeared were 5 involving 114.8KD etc. The protein bends combinized were 6 involving 128.7KD etc. The bends which had the resistance to cadmium stress in root is 27 in volving 166,9KD etc. The bends which disappeared were 198.7KD etc. There were 5 involving 83.4KD etc.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.1
• /
• pp.22-32
• /
• 1997

This experiment was conducted to obtain information for the cultivation of Korean valerian(Valeriana lauriei var. dasycarpa Hara) which will be useful for medicinal and aromatic resources. The effect of different temperature conditions, light intensities and soil water conditions on growth, yield and component of essential oil of V. fauriei were measured at the Dankook University, Cheonan, and a study on the shading treatment was at Umsung, Chungchongbukdo, and Jinbu, Kangwondo, in 1995. V. laudei was planted at five different temperature conditions, 10, 15, 20, 25 and 3$0^{\circ}C$, eight light intensity conditions, 1, 000, 2, 500, 5, 000, 20, 000, 30, 000, 40, 000, 50, 000 and 60, 000lux, six soil water contents, 30, 45, 55, 70, 80 and 90％ of the saturated soil, during growth stage. Shading treatment was three conditions, 0, 25 and 50％, during the daytime in field conditions. Photosynthesis had a highly significant relationship with temperature conditions in a quadratic regression model, from which the temperature for the plant growth was estimated to be 17.7$^{\circ}C$. A highly significant quadratic regression was noted between temperature and leaf width or root weight of V. fauriei. It was estimated from the regression equation that the optimum temperature for root growth was 20.3$^{\circ}C$. The content of essential oil and extract rate of root was the highest in the 15~2$0^{\circ}C$. Photosynthesis also was significantly affected by light intensity in a quadratic regression model, from which the optimum light intensity for the growth was estimated to be 40, 000lux. Root yield was more produced in Jinbu than that of in Umsung. The root yield was increased by the shading treatment in Umsung, whereas it was decreased by the shading treatment in Jinbu. The content of essential oil was not affected by the shading treatment of plants during the cultivation, while the compositions of components of essential oil were related to the growing locations. As soil water content was higher, the growth and content of root extract were increased. The optimum soil moisture for the growth of V. fauriei was 80~90％ of the saturated soil. In summary, the results indicated that the growth, yield and component of essential oil in V. fauriei were affected by environmental factors as well as soil moisture.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.3
• /
• pp.234-238
• /
• 1989

This study was carried out to find out favorable soil conditions to give good quality of Scutellaria baicalensis George for Korean medicine. The samples were collected from the 7 fields of An-dong gun and Eui-sung gun. The plants were grown under soils of different physicochemical properties and the available constituents from their roots were analyzed by HPLC. The average N, P, K contents in roots was determined to be 0.28-1.26%, 0.17-0.46% and 1.00-1.49%, respectively. The baicalin contents of root was determined to be 11.41-14.76% (An-dong gun) and 13.67-16.31% (Eui-sung gun). The contents of N, P in root were negatively correlated with the contents of exchangeable cations (K, Ca, Mg), clay and organic matter in soil, whereas it was not significant with the contents of total nitrogen and available phosphorus of surface soils. The baicalin contents was positively correlated with the exchangeable potassium contents in soil, but negatively correlated with nitrogen and phosphorus contents in the root of Scutellaria baicalensis George.

• Research in Plant Disease
• /
• v.18 no.3
• /
• pp.236-239
• /
• 2012

In July, 2009, proso millet (Panicum miliaceum), which showing the bacterial brown stripes on leaf sheaths, was collected in Miryang in Korea. Symptoms were systemic brown necrotic stripe lesions on the leaf sheaths and stems, and these symptoms were found in the entire field. The causal agent isolated from symptomatic plants was identified as an Acidovorax avenae subsp. avenae, based on its biochemical and physiological characteristics and also confirmed by the Biolog data and 16S rRNA gene sequence analysis. Also it caused hypersensitive response (HR) when it was inoculated onto the tobacco and tomato. It caused similar symptoms when inoculated onto proso millet. This is the first report of A. avenae subsp. avenae, the causal agent of bacterial brown stripe of the proso millet in Korea.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.6
• /
• pp.482-493
• /
• 2005

Biomass is originally photosynthesized from inorgainic compounds such as $CO_2$, minerals, water and solar energy. Recent studies have shown that anaerobic bacteria have the ability to convert recalcitrant biomass such as cellullosic or chitinoic materials to useful compounds. The biomass containing agricultural waste, unutilized wood and other garbage is expected to utilize as feed, food and fuel by microbial degradation and other metabolic functions. In this study we isolated several anaerobic, cellulolytic and chitinolytic bacteria from rumen fluid, compost and soil to study their related enzymes and genes. The anaerobic and cellulolytic bacteria, Clostridium thermocellum, Clostridium stercorarium, and Clostridium josui, were isolated from compost and the chitinolytic Clostridium paraputrificum from beach soil and Ruminococcus albus was isolated from cow rumen. After isolation, novel cellulase and xylanase genes from these anaerobes were cloned and expressed in Escherichia coli. The properties of the cloned enzymes showed that some of them were the components of the enzyme (cellulase) complex, i.e., cellulosome, which is known to form complexes by binding cohesin domains on the cellulase integrating protein (Cip: or core protein) and dockerin domains on the enzymes. Several dockerin and cohesin polypeptides were independently produced by E. coli and their binding properties were specified with BIAcore by measuring surface plasmon resonance. Three pairs of cohesin-dockerin with differing binding specificities were selected. Two of their genes encoding their respective cohesin polypeptides were combined to one gene and expressed in E. coli as a chimeric core protein, on which two dockerin-dehydrogenase chimeras, the dockerin-formaldehyde dehydrogenase and the dockerin-NADH dehydrogenase are planning to bind for catalyzing $CO_2$ reduction to formic acid by feeding NADH. This reaction may represent a novel strategy for the reduction of the green house gases. Enzymes from the anaerobes were also expressed in tobacco and rice plants. The activity of a xylanase from C. stercorarium was detected in leaves, stems, and rice grain under the control of CaMV35S promoter. The digestibility of transgenic rice leaves in goat rumen was slightly accelerated. C. paraputrificum was found to solubilize shrimp shells and chitin to generate hydrogen gas. Hydrogen productivity (1.7 mol $H_2/mol$ glucos) of the organism was improved up to 1.8 times by additional expression of the own hydrogenase gene in C. paraputrficum using a modified vector of Clostridiu, perfringens. The hydrygen producing microflora from soil, garbage and dried pelletted garbage, known as refuse derived fuel(RDF), were also found to be effective in converting biomass waste to hydrogen gas.