• Journal of Plant Biology
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• v.32 no.3
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• pp.203-214
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• 1989

Cosmarium candianum and C. obtusatum were sampled at 11 stations in Korea from October 1987 to June 1988. The samplings were cultured for study of the character variations in colonies. As a result, C. candianum var. candianum f. minutum, C. candianum var. depressum and C. candianum var. latius need not be separated from C. candianum, because 4 types in C. candianum complex occurred simultaneously in the same colony. It was changed the species reported as C. circulare Reinsch in Korea presently into C. candianum Delponte according to Compere's review. Because 2 types of C. obtusatum complex occurred at the same colony, C. obtusatum var. beanlandii need not separated from C. obtusatum.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.102-106
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• 2003

The uptake of $^{14}C$-2, 4, 6-trinitrotoluene (TNT) in hydroponics was studied using onion plants. Of the total TNT mass (5 $\mu\textrm{M}$ concentration), 75% was in the roots, 4.4% in the leaves, and 21% in the external solution at 2 days, The percent distribution in roots was lower with higher concentration in the external solution, but in leaves it was comparable at all concentrations (5-500 $\mu\textrm{M}$). Root concentration factor (RCF) in hydroponics was more than 85 in constant hydroponic experiment (CHE) at 5 $\mu\textrm{M}$ and 150 in non-constant hydroponic experiment (NHE) at 5 $\mu\textrm{M}$. The maximum RCF values in the hydroponic system were greater with lower solution concentration. Transpiration stream concentration factor (TSCF) values in the present study (NHE only: 0.31-0.56) were relatively similar to the values with predicted values (0.43-0.78), increasing with higher external TNT concentration. For phytotoxicity tested in hydroponics and wet paper method, 500 $\mu\textrm{M}$ was toxic to onion plant, 50 $\mu\textrm{M}$ was non-toxic for plant growth but limited the transpiration rate, and 5 $\mu\textrm{M}$ was non-toxic as control.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.151-156
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• 2001

This study was conducted to obtain the transformed alfalfa (Medicago sativa L.) plants with thermotolerance gene (BcHSP17.6) using Agrobacterium tumefaciens LBA4404 and we confirmed the transformed gene from the regenerated alfalfa plants. The expression vector, pBKH4, harboring BcHSP17.6 gene was used for production of transgenic alfalfa plants. In a process for transformation, the callus of alfalfa was cocultivated with Agrobacterium tumefaciens and transformed calli were selected on kanamycin-containing SH-3-kc medium to regenerate into into the plant. The complete transgenic alfalfa plants were produced by cultivation for about 4 months on several regeneration media, SH-nk-c, SH-l lb-c, SH-sp-c, and SH-IBA. The transgenic alfalfa plants were analyzed by isolation of genomic DNA and PCR/Southem blot.

• Korean Journal of Veterinary Research
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• v.58 no.3
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• pp.147-151
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• 2018

We assessed the seroprevalence of Coxiella burnetii (C. burnetii) in cattle on Ulleung Island, Korea in a population-based follow up study for 4 years and determined the spatial distribution and risk factors associated with C. burnetii. The seroprevalence of C. burnetii was determined to be 1.4-2.0% during 2011-2014. Overall, nine cattle from three farms that tested seropositive showed C. burnetii antibody seroconversions between 2011 and 2014. The number of seropositive cattle was low, suggesting that movement of and contact between animals was possible risk factors for the transmission of C. burnetii.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.209-213
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• 1996

배나무잎 이상반점증상의 발병환경 조건을 조사하고자 실험한 결과 주간 23$^{\circ}C$, 야간 18$^{\circ}C$ 온도조건에서 병징발현이 가장 심하였고 이보다 높은 온도인 28/23$^{\circ}C$와 낮은 온도인 18/13$^{\circ}C$에서는 발병이 아주 적었다. 배나무잎에 봉지를 피복하면 발병이 전혀 없거나 극히 저조하였다. 이것은 봉지내의 온도가 최고 46.8$^{\circ}C$까지 올라가 고온에 의하여 발병이 억제된 것으로 생각된다. 이병주 토양과 건전주 토양의 화학성을 조사한 결과 이병주 토양에서는 건전주 토양보다 유효인산량이 많게 나타났다. 토양수분이 많거나 적었을 때는 병징발현이 다소 늦어지기는 하나 최종 조사시 발병정도는 큰 차이를 나타내지 않았다.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.55-57
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• 1999

Botrytis cinerea was isolated from a gray mo이 leaf lesion on persimmon in fields of Kyeonsangnam-do from 1996 to 1998, and etiological study was conducted including physiological characteristics. It formed gray mold lesion with light green color on leaves of persimmon (Diospyros kaki). The temperature range for mycelial growth was between $5^{\circ}C$ and $30^{\circ}C$ with the optimum temperatures of $20^{\circ}C$ to $25^{\circ}C$. Conidia were oviod, cylindric, and colorless and their dimensions in culture were $8.4~11.5\times7.0~8.9\mu\textrm{m}$. The optimum temperature of conidial germination was $25^{\circ}C$. Sclerotia on potato dextrose agar medium were well formed and brownish condiophores were observed with their size of $18.5~64.9\times4.5~8.0\mu\textrm{m}$. Symptoms on artificially inoculated plants were similar to those of gray mold disease on persimmon caused by Botrytis cinerea in fields.

• Journal of Plant Biology
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• v.38 no.4
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• pp.359-364
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• 1995

As the first step to elucidate the relationship between the structure and function of CTP:phosphocholine cytidylyltransferase (EC 2.7.7.15) in plants, the partial nucleotide sequence of soybean cytidylyltransferase cDNA was determined using a polymerase chain reaction (PCR). Degenerate oligonucleotide primers were synthesized from the conserved region revealed from the rat and yeast cytidylyltransferase DNA sequences. The catalytic domain region showed 78 and 76% homology with the rat and yeast amino acid sequences, respectivly. The hydropathy profile indicated that the C-terminal non-catalytic portion of the protein was very hydrophilic, and in the region between the catalytic domain and the C-terminal region, there was a large amphipathic $\alpha$-helical domain that was believed to bind the membrane surface in the active formation. There are 7 potential sites for phosphorylation by protein kinase C and 4 potential sites for phosphorylation by Ca2+/calmodulin kinase within the determined sequence.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.425-436
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• 2015

The carbon cycle came into the spotlight due to the climate change and forests are well-known for their capacity to store carbon amongst other terrestrial ecosystems. The annual organic carbon of litter production, forest floor litter layer, soil, aboveground and belowground part of plant, standing biomass, net primary production, uptake of organic carbon, soil respiration, etc. were measured in Mt. Worak in order to understand the production and carbon budget of Quercus serrata forest that are widely spread in the central and southern part of the Korean Peninsula. The total amount of organic carbon of Q. serrata forest during the study period (2010-2013) was 130.745 ton C ha^-1. The aboveground part of plant, belowground part of plant, forest floor litter layer, and organic carbon in soil was 50.041, 12.510, 4.075, and 64.119 ton C ha^-1, respectively. The total average of carbon fixation in plants from photosynthesis was 4.935 ton C ha^-1 yr^-1 and organic carbon released from soil respiration to microbial respiration was 3.972 ton C ha^-1 yr^-1. As a result, the net ecosystem production of Q. serrata forest estimated from carbon fixation and soil respiration was 0.963 ton C ha^-1 yr^-1. Therefore, it seems that Q. serrata forest can act as a sink that absorbs carbon from the atmosphere. The carbon uptake of Q. serrata forest was highest in stem of the plant and the research site had young forest which had many trees with small diameter at breast height (DBH). Consequentially, it seems that active matter production and vigorous carbon dioxide assimilation occurred in Q. serrata forest and these results have proven to be effective for Q. serrata forest to play a role as carbon storage and NEP.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.159-162
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• 1998

Effect of temperature on oviposition and developmental period of Oulema oryzae K. on riceplant were investigated. With the given set of temperatures of 15, 20, 23, 25, and 28"C, developmentalperiod from egg to adult emergence was shorten as temperature increased. Average number of eggs perfemale 0. oryzae increased as temperature increased from 15$^{\circ}$C to 23"C, then decreased at 25$^{\circ}$C and 28"C. Based on this result, developmental threshold temperatures for egg was estimated to be 6.4"C. Totaleffective temperatures above the thresolds required for hatching were estimated to be 75.8 degree-daysfor egg. It seemed that the optimum temperature for oviposition of Oulema oryzae on rice plant was 23"C.a oryzae on rice plant was 23"C.quot;C.

• Journal of Plant Biology
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• v.33 no.2
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• pp.111-118
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• 1990

In order to characterize the chloroplasts of Korean ginseng as a semi-shade plant and radish as a sun plant, effects of growth light intensity on photosynthetic electron transport (PS) activity in chloroplasts and superoxide (O2.-) production in thylakoid membrane by irradiation were investigated. High-light chloroplasts of both plants showed higher PS activities than those grown under ow growth light intensity. High PS II and low PS I activities in ginseng chloroplasts (ratio of PS II/PS I : 1.1) were observed, but radish chloroplasts showed low PS II and high PS I activities (ratio of PS II/PS I : 0.3). PS II activity of both plants was little affected by temperature in range of 15-35$^{\circ}C$. Activities of whole -chain (PS II+I) in ginseng and PS I in radish were increased at high temperature (4$0^{\circ}C$). Preincubation of chloroplasts at 4$0^{\circ}C$ during 30 min, as a mild heat stress, caused rapid decrease in PS II and PS II+I activities of both plants. However PS I activity was not decreased in ginseng and rather increased in radish. O2.- production (NBT reduction) in Mehler reaction in the thylakoid membrane was inhibited by DCMU in both plants. DMBIB inhibited O2.- production in ginseng, but radish was insensitive to DMBIB. Electron flow system in ginseng thylakoid membrane was more susceptible to damage of photooxidation than that of radish.