• Journal of Plant Biology
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• 제36권2호
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• pp.133-140
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• 1993

The photosynthetic activities in relation to oxygen evolution rates, quantum yield, CO2 uptake rates and room temperature chlorophyll fluorescence were investigated in cotyledons of cucumber seedlings exposed to low temperature (at 4$^{\circ}C$) for 24 h. Light-chilling caused more inhibition on light-saturated maximum oxygen evolution rates, quantum yield, and CO2 uptake rates than dark-chilling did in the cucumber plant. Light-chilling induced more marked increase in Fo and decrease in (Fv)m/Fm than dark-chilling did in the room temperature chlorophyll induction kinetics. The above results affected by chilling in the light are considered to be associated with the partial damage of the reaction center of PS II and the decreased photosynthetic activities. There occurred a large decrease in qQ with little change in qNP in the light-chilling plant. When light- and dark-chilled plants were recovered at room temperature for 24 h and their chlorophyll fluorescences were induced with light doubling technique, light-chilled plants showed more smaller magnitude and rate of fluorescence relaxation than dark-chilled plants. These suggest that light-chilling might cause some alterations in transthylakoid pH formation, and that photosynthetic apparatus of cucumber cotyledons is more susceptible to light-chilling. In the fast fluorescence induction kinetics, FR was decreased by 60% in the light-chilled plants with reference to $25^{\circ}C$ light-grown plants, while the dark-chilled plants showed a decreased rate of only 20% with reference to $25^{\circ}C$ dark-treated plants for 24 h, indicating that cucumber seedling is very sensitive to chilling stress. So, it is certain that chilling injury to the photosynthetic apparatus is strongly dependent on the presence of light in cucumber seedlings.

• 한국작물학회지
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• 제27권3호
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• pp.206-217
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• 1982

지대별 이앙기의 차이가 수도의 지엽과 인각의 양분흡수이용에 미치는 영향을 분석 조사하였던 바 다음과 같은 결과를 얻었다. 1. 출수지연은 지엽중 전질소함유율을 높이고 규산의 흡수를 저해하여 불임을 야기 시키는데 그 경향은 만식과 고지대일수록 뚜렷하다. 2. 지엽에 축적된 전질소함유율과 규산함유의 다소는 수량을 좌우하는 유의적인 상관관계를 이룬다. 3. 만식과 등숙이 불량한 인각일수록 전질소함유율은 높으나 규산의 흡수는 상대적으로 낮아지는 상관관계를 나타낸다. 4. 인각의 무기성분함유율은 출수후 등숙기온에 영향을 받는데 등숙기온이 높을수록 인각의 인산, 가리, 칼슘, 규산의 함유율은 증가하나 전질소 함유율은 낮아져 인각의 무기성분조성이 불임과 밀접한 관계가 있음을 암시하여 준다.

• The Korean Journal of Ecology
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• 제7권3호
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• pp.170-176
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• 1983

The results obtained from the experiments conducted to investigate Cruciferae plants in rape dependent on the amount of applied fertilizer in aspects of mineral nutrient uptake and on the effects of the composition of oil quality are as follows: Absorption of mineral nutrients in the respective pars of the plant body was high in nitorgen in the order of leaf and stem

• 생물환경조절학회지
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• 제9권4호
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• pp.185-192
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• 2000

본연구는 시설내 다양한 환경조건하에서 오이의 호흡속도에 관한 수리적 모형을 개발하고자 실시하였다. 개개 오이 식물에 대한 총광합성속도의 8.55%가 호흡에 사용되었다. 생장호흡계수는 0.0935로 추정되었고 유지호흡속도는 24$^{\circ}C$ 온도에서 0.00158g C$H_2O$.g$^{-1}$.h$^{-1}$로 추정되었다. 그리고 그것은 온도상승에 따라 지수적으로 증가하였다. 호흡속도는 저장 탄수화물량이 낮아짐에 따라 비례적으로 감소했고 뿌리의 이온흡수호흡속도는 0.6648g C$H_2O$.(gN)$^{-1}$로 추정되었다.

• 식물조직배양학회지
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• 제26권2호
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• pp.99-102
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• 1999

Glucose - induced arginine transport system was induced by a exogenous application of NH$_4$^+ ion. The uptake rate of arginine (Arg) depended on the external NH$_4$^+ ion concentration. The uptake rate was inhibited by the presence of NH$_4$^+ ion within 1 min, whereas it increased maximally after 30 min. Glucose and NH$_4$^+ ion induced the same arginine transport system. Km value of Arg transport systems was 2 $\mu$M, and V_(max) was 60 $\mu$mol^(-1) . h . g fresh weight^(-1) for NH$_4$^+ ion and 174 $\mu$mol^(-1) . h . g fresh weight^(-1) for glucose induced transport system. But, the transport system of Glu for glucose and NH$_4$^(-1) ion induced had different Km values. Km value of Glu was 285 $\mu$M for glucose - and 58 $\mu$M for NH$_4$^+ ion induced transport system. Thus, NH$_4$^+ ions play a important role as inducer for the glutamine transport system. NH$_4$^+ ion induced glutamine system was inhibited over 90% by cycloheximide. We concluded that a new carrier protein for glutamine was induced by NH$_4$^+ ion.

• 한국작물학회지
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• 제51권1호
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• pp.107-111
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• 2006

This study was to verity that the uptake inhibition and accumulation of nitrogen in different potassium levels. Lettuce was used as model plant in this study and grown in pot of 10cm's in diameter and depth with mixture media of vermiculite and perlite under supply of different culture solution for three weeks. Nitrogen absorption at root was inhibited by increased potassium concentration in nutrient solution, and nitrate accumulation of plant was depended on absorption of nitrogen because nitrate content of 0 K level was 4-5 times higher than that of 2 K level, Concentration of ascorbic acid was decreased by increasing the nitrogen absorption, since ascorbic acid (AsA) content of 2K level was higher than those of OK level in both of old leaf and flesh leaf.

• Journal of Microbiology and Biotechnology
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• 제21권11호
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• pp.1127-1142
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• 2011

The aim of this investigation was to select effective Pseudomonas sp. strains that can enhance the productivity of soybean-wheat cropping systems in Vertisols of Central India. Out of 13 strains of Pseudomonas species tested in vitro, only five strains displayed plant growth-promoting (PGP) properties. All the strains significantly increased soil enzyme activities, except acid phosphatase, total system productivity, and nutrient uptake in field evaluation; soil nutrient status was not significantly influenced. Available data indicated that six strains were better than the others. Principal component analysis (PCA) coupled cluster analysis of yield and nutrient data separated these strains into five distinct clusters with only two effective strains, GRP3 and HHRE81 in cluster IV. In spite of single cluster formation by strains GRP3 and HHRE81, they were diverse owing to greater intracluster distance (4.42) between each other. These results suggest that the GRP3 and HHRE81 strains may be used to increase the productivity efficiency of soybean-wheat cropping systems in Vertisols of Central India. Moreover, the PCA coupled cluster analysis tool may help in the selection of other such strains.

• Mycobiology
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• 제33권1호
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• pp.41-50
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• 2005

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. The effect of arbuscular mycorrhizal fungi (Am) on remediation efficacy of wheat, mungbean and eggplant grown in soil spiked with polyaromatic hydrocarbons (PAH) was assessed in a pot experiment. The results of this study showed that Am inoculation enhanced dissipation amount of PAHs in planted soil, plant uptake PAHs, dissipation amount of PAHs in planted versus unplanted spiked soil and loss of PAHs by the plant-promoted biodegradation. A number of parameters were monitored including plant shoot and root dry weight, plant tissue water content, plant chlorophyll, root lipid content, oxido-reductase enzyme activities in plant and soil rhizosphere and total microbial count in the rhizospheric soil. The observed physiological data indicate that plant growth and tolerance increased with Am, but reduced by PAH. This was reflected by levels of mycorrhizal root colonization which were higher for mungbean, moderate for wheat and low for eggplant. Levels of Am colonization increased on mungbean > wheat > eggplant. This is consistent with the efficacy of plant in dissipation of PAHs in spiked soil. Highly significant positive correlations were shown between of arbuscular formation in root segments (A)) and plant water content, root lipids, peroxidase, catalase polyphenol oxidase and total microbial count in soil rhizosphere as well as PAH dissipation in spiked soil. As consequence of the treatment with Am, the plants provide a greater sink for the contaminants since they are better able to survive and grow.

• 한국작물학회지
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• 제46권3호
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• pp.253-259
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• 2001

나지와 작물재배조건의 밭토양에서 질소 공급원으로 질소질 비료 및 완숙 회비를 시비함에 따른 작물체의 생육 및 양분 흡수와 토양내 양분의 이동, 지하수로의 용탈 가능성을 추정하여 시비양분의 행방을 추정하기 위하여 lysimeter에 무비방 임구, 무비무재배 제초구, 무비재배구, 질소 토양처리구(16, 32, 64kg/10a), 질소+퇴비 토양처리구(16+800, 32+1600, 64+3200 kg/10a), 질소 수용액처리구(16, 32kg/10a), 질소보비(32kg/10a)소식 및 밀식구 13 처리로 하여 전작물 옥수수와 후작물 감자의 생육 및 양분의 흡수, 용탈정도를 조사하였다. lysimeter를 통하여 용탈된 물의 양은 나지구(T1, T2)가 작물 재배구들보다 현저하게 많았다. 시비량을 증가시킬수록 전작물(옥수수)과 후작물(감자)의 식물체내 질소함량은 증가하는 경향이었다. 작물체의 생육은 수용액시비구가 토양시비구에 비해 유의하게 양호하였고, 질소흡수율도 수용액시비구가 상대적으로 높았다. 옥수수 및 감자의 건물수량은 질소.퇴비보비구와 증량구가 큰 차이가 없었으나, 식물체내 N, Ca Na, K, Mg의 함량은 시비량이 많을수록 높아지는 것으로 나타났다. 옥수수, 감자의 총질소 함량과 다른 무기성분의 흡수량간에는 Ca, K, Mg과 각각 0.89$^{**}$ , 0.94$^{**}$ , 0.87$^{**}$ 로 매우 높은 상관성을 유지하고 있어 질소의 흡수가 다른 무기성분의 흡수에 영향을 미치고 있음을 보여주었다. 식물체의 실제적인 질소흡수량은 시비량을 증가시킬수록 증가하였으나, 비료로 시용된 질소의 흡수율은 소비구(T4)가 54.9%로 가장 높은 반면, 증량구에서는 31.0-34.0%로 낮아졌다. 토양잔존율은 시비량이 많을수록 높아져 다비구일수록 용탈 가능성이 커지는 것으로 나타났다.

• Applied Biological Chemistry
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• 제51권2호
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• pp.108-113
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• 2008

Azoxystrobin과 kresoxim-methyl의 오이 흰가루병 방제 효과를 증진시키기 위하여 오이 잎에서 유효성분의 침투성을 증진시킬 수 있는 계면활성제를 선발하고 이를 함유하는 제제의 오이 흰가루병에 대한 방제효과를 측정하였다. 수화제 현탁액으로 살포한 azoxystrobin은 오이 잎에 거의 침투되지 않았으나 polyoxyethylene monohexadecyl ether(CE-12, 에틸렌옥사이드 12몰 중합물)를 500 mg/l 첨가함으로써 침투성이 분무 24시간 후에 25.7%까지 증가하였다. 수화성 입제를 물에 희석하여 100 mg/l의 농도로 처리한 kresoxim-methyl은 4.1%만이 오이잎에 침투되었지만 polyoxyethylene monooctadecyl ether(에틸렌옥사이드 14몰 중합물)를 1,000 mg/l 첨가하였을 때 침투율이 58.0%까지 증가하였따. 계면활성제 CE-12(500 mg/l)에 의한 오이 엽면 침투율은 같은 유효성분 농도(50 mg/l)에서 kresoximmethyl이 azoxystrobin보다 2배 이상 높았다. 침투성 증진용 계면활성제를 첨가한 azoxystrobin 수화제 현탁액은 수화제 처리 대조구보다 온실 내 오이 흰가루병 방제 효과를 증가시켰지만 그 차이는 크지 않았다. 그러므로 azoxystrobin의 경우에는 침투성 증진이 오이 흰가루병에 대한 방제 효과를 크게 높일 수 있는 실용적인 방법은 아니었다. 반면에 kresoxim-methyl은 유효성분의 높은 증기압 때문에 동절기 말폐된 온실 내에서는 침투성 증진에 따른 오이 흰가루병 방제 효과 변화를 측정할 수 없었다.