• Journal of agriculture & life science
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• v.46 no.4
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• pp.93-99
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• 2012

This study was conducted to investigate photosynthetic characteristics of two-year-old of Adenophora triphylla var. japonicum grown under control (full sunlight) and three different shading treatment (25, 50, and 75% shading treatment). Total chlorophyll contents like chlorophyll a and b content had not significant difference among treatments. Net photosynthetic rate of control and 25% treatment were higher than 50% and 75% treatment. Seedlings grown under full sunlight showed the highest photosynthetic activity such as photosynthetic rate, stomatal conductance and intercellular $CO_2$ concentration except for water use efficiency which was relative higher under 50% and 75% treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.506-515
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• 2003

Six barley varieties that showed different degree of drought tolerance were grown with and without drought stress treatment (control), and investigated for the temporal changes in growth and several physiological traits after drought treatment. Soil water potential was -0.05 ㎫ at the initial stage of drought treatment and dropped to -0.29 ㎫ at 19 days after withholding irrigation. Soil water potential (SWP) maintained at -0.05 ㎫ in the control. The dry weight (DW) under the drought treatment were reduced compared to the control as follows: Dicktoo-S (short awn), 69% ; Dicktoo-L (long awn), 70%; Dicktoo-T (tetra), 86%; Dongbori-1, 69%; Suwonssalbori-365, 55% and Tapgolbori, ,37%. Dicktoo lines and Dongbori-1 were more tolerant than Suwonssalbori-365 and Tapgolbori. Leaf relative water contents (RWC) and leaf water potential (LWP) decreased obviously under the drought condition, the decrease being greater especially in the less drought-tolerant barley genotypes. Dongbori-1 and Dicktoo-L in drought treatment showed net photosynthesis of 38% and 17% compared to the control, respectively, and the other four genotypes much lower photosynthesis of 1.1% to 7.0%. Stomatal conductance, mesophyll conductance, and the photochemical efficiency (Fv/Fm) of PS II were reduced by drought treatment, the reduction being greater in drought-sensitive genotypes. The drought-tolerant genotypes had greater osmotic adjustment (OA) capacity under water stress. Thus, the decrease of RWC and LWP was lower and the turgor pressure conservation capacity was higher under water stress in drought-tolerant genotypes. Drought-tolerant genotypes showed less decrease of photosynthesis because stomatal conductance, mesophyll conductance and the ratio (Fv/Fm) of the variable to maximal fluorescence of drought-resistant genotype was decreased less in the drought stress condition. In conclusion, the drought-tolerant genotypes had better water conservation capacity through efficient OA, and this led to the lower decrease of photosynthesis and growth in water stress condition.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.99-103
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• 1994

The herbicide bialaphos is a potent inhibitor of glutamine synthetase in higher plants. A bialaphos resistance (bar) gene encoding for an acetyltransferase was isolated from genomic DNA of Pseudomonas syringae pv tabaci. The bar gene was ligated to the binary vector pBI121. Pistils of tobacco plane were heated with the bar gene containing plasmid DNA at various times after pollination. When the treatment was applied at 30 and 40 h after pollination, a number of transgenic plants were obtained. Premary transformation (T$_{0}$ generation) and their progenies (T$_1$T$_2$) were resistant to both bialaphos and kanamycin at a dosage lathal to untransformed control plants. Stable integration of bar gene into chromosomal DNA was proven by Southern blot analysis of genomic DNA isolated from T$_1$progenies. These results show that the bialaphos resistant plane could be obtained by treatment to pistils with the exgenous bar gene through the fertilization cycle of tobacco.o.

• 한국해양학회지
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• v.26 no.4
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• pp.324-331
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• 1991

Laboratory experiments were undertaken in mixing chamber to study the water-in-oil emulsion formation tendency, stability and formation rate of 16 crude oils. Arabian, Iran, Dubai, Isthmus and Daekyung crudes showed high emulsion formation tendency and had water contents of 80-90%. Emulsions of crude oils of middle East were very stable, while Isthmus and Daekyung sudes formed unstable emulsion. Emulsion formation tendency rate, and stability showed significant correlations with asphaltene content of crude oil. To evaluate the possibility of preventing mousse formation, inhibition ability of several dispersants and demulsifier was tested. They inhibited mousse formation at 0.1-0.2% concentrations (v/v). Emulsion inhibition by chemical treatment delayed the time of formation, but did not decrease water content. Demulsifying ability of dispersants and demulsifier was tested because biscous emulsion causes formidable problems in skimming, pumping and recovery operation. British demulsifier Alcohol 0 showed excellent emulsion breaking efficiency at 0.1% of emulsion Vol..

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.328-333
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• 1983

Due to fast industrialization and reduced agricultural population, there has been increased farm mechanization to reduce the labor requirement. In rice production, mechanical transplanting has been increasingly popular due to the heavy labor requirement in hand transplanting and development of convenient transplanters. For mechanical transplanting, rice seedlings is grown in boxes with limited soils under super dense population, thus short period of exposure to unfavorable temperature and poor water management would cause severe damage to rice seedlings such as seedling damping off and the similar physiological disorders. Several chemicals were evaluated for their effectiveness to control the disease and disorders, and other effects as plant growth stimulants. 3-hydroxy-5-methylisoxazole-a soil fungicide, Metalozyl-a fungicide which controls mildew, SF 8002-the composite of above two chemicals, and Isoprothiolane-a fungicide which controls rice blast were found to be effective controling seedling damping off and similar physiological disorders, and improvement of physiological characteristics of the seedlings such as the amount of bleeding sap, rooting ability, negative geotrophism, and regrowth after cutting. The results indicated that the chemicals will be very effective raising healthy seedlings even under unfavorable environments by the improvement of physiological activities of seedlings and preventing seedling damping off and the similar physiological disorders.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.242-249
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• 1987

Physicochemical properties on heat-moisture treatment of sweet potato starch were investigated. Starch granules of sweet potato observed by photomicroscope, polarized-light microscope and scanning electron microscope were round and polygonal. X-ray diffraction pattern was changed from Ca-pattern to A-pattern upon heat-moisture treatment. Water binding capacity was drastically increased as the moisture level was increased. The swelling power and solubility at the same temperature were decreased by heat-moisture treatment. Transmittance of 0.1% starch suspensions was increased rapidly from $65^{\circ}C$ in case of untreated starch and from $70^{\circ}C$ in case of treated starch. The starch on heat-moisture treatment was gelatinized over higher temperature range than the untreated starch.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.313-314
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• 2003

분할형 극세사 직물은 서로 상용성을 가지지 않는 nylon/polyester의 용융고분자물을 복합방사법에 의하여 filament 형태로 방사한 후 이를 제직, 편성의 방법으로 포를 제조하고 알칼리 용액에 처리함으로써 생산되어 진다. 따라서 극세사 직물은 일반적으로 소수성의 합성섬유로 이루어졌음에도 불구하고 알칼리 가수분해에 의하여 분할된 섬유 사이의 수많은 모세관에 의하여 높은 흡수성과 수분전이능력을 갖게 된다. 이러한 이유로 극세사 직물은 일반적인 와이퍼의 용도뿐만이 아니라 food service, medicine, 반도체를 제조하는 clean room등으로 그 응용범위를 넓혀 가고 있다. (중략)

• KOREAN POULTRY JOURNAL
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• v.34 no.11 s.397
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• pp.60-63
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• 2002

우리나라에서 계분은 귀한 비료로 사용되어 왔으며, 양계협회 능력검정소가 성북구 공릉동에 있을 때만 해도 주변의 배밭 주인들이 계분을 사기 위해 경쟁하였고, 계분판매 수입도 크지는 않지만 검정소의 수입항목이 되었던 것이 새롭다. 가축분뇨가 환경오염의 주범으로 양축농가가 구속된 때에도 닭의 경우는 다른 가축과 달리 총 배설강을 통해 분뇨가 혼합상태로 배설되므로 그 특성상 수분함량이 적어 큰 문제가 되지 않았었다. 그러나, 양계 규모가 커짐에 따라 주변의 민원과 절대적인 계분 발생량이 많아져 어떤 형태로든 처리하지 않을 수 없게 되었다.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.77-82
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• 2001

This study was investigated to know the effects of diflubenzuron(DFB) on the larval silkgland development of the silk-worm, Bombyx mori (L.). It has been known as a prohibitor of chitin synthesis mostly on the species of the Order Lepidoptera. In this work, the effects of the DFB concentrations (2.5$\times$10$\^$-1/,2.5$\times$10$\^$-2/, and 2.5$\times$10$\^$-3/$\mu\textrm{g}$/$\mu$l on the various larval stages, were investigated in terms on the silkgland. The macro- and microstructure of cell membrane of silkgland, and the differences of silkgland weight and water contents treated by DFB are also surveyed. As the tesults, the silkgland weight depended sensitively on not the DFB concentration but the DFB treatment period. The longer DFB treatment period, the lighter dried silkgland weight and the heavier water content of the silkgland. White opaque(WO) emerged in the middle silkgland of DFB treated larva. From the scanning election microscope observation, the cell membrane of silkgland of DFB treated larva was distinctly more compact compared to that of control. The WO was evidently resulted from the obstacles of normal transformation of silk protein through the cell membrane of middle silkgland.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.1
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• pp.79-87
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• 2005

세계적으로 가장 널리 사용되는 제초제의 하나인 EPTC(s-ethyl-N,N'- dipropylthiocarbamate)에 대하여, 이를 분해하는 미생물의 토양 내에서의 직접 증식과 이를 함유한 토양(INOCULUM)의 토양내 EPTC 분해촉진을 위한 접종재(inoculant)로서의 효용성을 조사하였다. 한 차례의 EPTC(20mg EPTC/kg 토양)처리에 의해, 순수분리 없이 토양 내에서, EPTC-분해 미생물의 수가 $10^2$ 수준에서 $10^5$ 수준으로 약 $10^3$배 증식되었으며, EPTC 분해속도 또한, 토양으로부터 추출 가능한 EPTC가 초기 EPTC농도(20mg EPTC/kg 토양)의 20%까지 떨어지는데 걸리는 시간을 기준으로 할 때, EPTC처리 전의 20여 일에서 EPTC 처리 후에는 1일 이내로 빨라졌고, 이 토양의 EPTC 분해능력은 토양내의 EPTC 초기농도가 토양 kg당 2,000mg일 때까지도 크게 저해되지 않았다. 이 토양(INOCULUM)을 EPTC로 오염된 토양에 접종(0.05-5%, w/w)하였을 때, 오염된 토양 내에서의 EPTC 분해속도가 크게 향상되었다. 이 토양의 EPTC 분해능력은, 저온($10^{\circ}C$ 이하)의 습한 상태(수분함량 25%)에 보관하였을 때, 최소 6개월간 유지되었다. 본 연구는 EPTC-분해 미생물이 토양 내에서 쉽게 증식됨과, 이를 함유하는 토양(INOCULUM)이 토양내의 EPTC 분해 촉진을 위한 접종재로서 매우 효과적임을 확인하였고, 이 같은 방법은 다른 화합물과 그에 오염된 토양에도 적용될 수 있을 것으로 기대된다.