• The Korean Journal of Ecology
• /
• 제15권2호
• /
• pp.157-172
• /
• 1992

Studies were conducted to evaluate the differential al tolerance of suwon 205 and olmil wheats grown is nutrient solution and determine the impact of NH4+-N or Ca2+ nutrition of the response of the two wheat vareties to al. In various concentrations of al, olmil induced lower ph levels than suwon 205 in nutrient solutions and the reduction of root length and dry weight was greater in olmil than in suwon 205. The uptake of al was greater in root than in shoot of the two wheat varieties, but more increased in root of olimil. also the uptake of ca, mg, k and p was inhibited by al especialy decrease of ca and p uptake in roots of olmil was more pronounced than in those of suwon 205. In nutrient solutions that contained NH4+-N plus 9ppm al, the ability of both varienties to raise the ph was reduced as the level of NH4+-N in nutrient solutions was increased, and al-sensitive olimil induced lower ph than did al-tolerant suwon 205. al toxicity was intensified by increasing the concentration of NH4+-N in nurient and toxic effect was greater in olmil. al toxicity in the two wheat varieties was steadily increased as the ca level of nutrient solution was reduced, sepecialy this effect was stronger in al-sensitive olmil than in al-tolerant suwon 205.

• Journal of Ecology and Environment
• /
• 제34권3호
• /
• pp.315-322
• /
• 2011

We investigated the effect of Pb uptake by Pinus densiflora and the Pb fraction in forest soil. We also investigated the change in soil physicochemical characteristics, microbial activity, and root exudates of Pinus densiflora in Pb-contaminated soils. Three-year-old pine seedlings were exposed to 500 mg/kg Pb for 12 months. The metal fractions were measured using sequential extraction procedures. Additionally, factors that affect solubility (three soil enzyme activities and amino acids of root exudate compounds) were also determined. The results showed that Pb contamination significantly decreased enzyme activities due to soil characteristics. In addition, organic matter, nitrate content, and Pb concentration were time dependent. The results indicate that changes in the Pb fraction affected Pb uptake by pine trees due to an increase in the exchangeable Pb fraction. The concentrations of organic acids were higher in Pb-spiked soil than those in control soil. Higher rhizosphere concentrations of oxalic acid resulted in increased Pb uptake from the soil. These results suggest that pine trees can change soil properties using root exudates due to differences in the metal fraction.

• 한국초지조사료학회지
• /
• 제28권2호
• /
• pp.71-74
• /
• 2008

유채 품종간의 황 이용률을 비교하기 위하여 10가지 유채 품종(Mokpo, Tamra, Youngsan, Naehan, Saturnin, Akela, Mosa, Capitol, Pollen and Colosse)을 정상적인 황 공급(2.0 mM) 조건하에서 재배하여 품종별로 황 흡수량을 측정하였다. 또한 유채 품종간의 생육 특성을 비교하기 위해 잎의 수, 잎의 길이, 잎의 넓이 및 뿌리의 길이를 조사하였다. 그 결과, 모든 유채품종에서 잎의 수, 잎의 길이와 넓이는 별다른 차이는 나타나지 않았다. 뿌리 길이는 Saturnin에서 36.3cm로 가장 길게 나타났다. Saturnin, Youngsan과 Mokpo에서 ${SO_4}^{2-}$ 흡수량이 대체적으로 높았고 Mosa와 Pollen에서 ${SO_4}^{2-}$ 흡수량 상대적으로 낮았다. ${SO_4}^{2-}$ 흡수량이 높은 Saturnin와 Mokpo에서 ${NO_3}^-$ 흡수량도 높게 나타났다.

• 생명과학회지
• /
• 제18권2호
• /
• pp.154-161
• /
• 2008

염분에 대한 벼 유식물의 생리학적 광화학적 반응을 잎의 상대수분함량, 엽록소 형광 및 뿌리의 수분흡수를 통하여 연구하였으며, 벼 유식물이 농도가 다른 NaCl에 노출되었을 경우, 500 mM 이상의 농도와 4일, 5일간 스트레스를 준 처리구에서 식물체의 외관상 심각한 장해 징후가 나타났다. 500 mM에서는 5일간, 1,000 mM에서는 4일간 스트레스를 준 처리구와 NaCl를 처리하지 않은 대조구 간의 광합성 Fv/Fm에서 유의성이 있는 차이가 나타났으며, 그러나 뿌리 수분흡수에서는 Fv/Fm에 비해 스트레스 기간이 짧은 2일에서도 수분흡수의 차이가 나타나기 시작했다. NaCl에 노출된 식물에서 잎의 상대수분함량은 외부 염분의 농도가 증가하구 스트레스 기간이 길어짐에 따라 점차 감소하였다. 잎의 상대수분함량 결과에서 1,000 mM 농도로 1일간 처리된 경우(88%)와 비교했어 2일 이상 NaCl를 처리한 경우들(58-67%)에서 보다 낮은 수분함량을 보였다. NaCl 스트레스는 4일과 5일간 처리한 경우 etiolate된 벼 유식물의 광 유도 녹화과정에서 NaCl 농도가 증가함에 따라 직선적으로 심하게 억제하였다(각각의 $R^2$=0.812과 0.918). 염분 스트레스 기간과 NaCl농도가 증가되었을 때, NaCl의 농도가 같음에도 잎의 Fv/Fm보다는 뿌리의 수분흡수가 더 민감하게 반응하는 것으로 보아 잎에서의 장해보다는 뿌리에서의 반응이 먼저 일어나는 것으로 보인다.

• Journal of Applied Biological Chemistry
• /
• 제44권1호
• /
• pp.16-19
• /
• 2001

Soybean plants(Glycine max [L.] merr.) inoculated with Bradyrhizobium japonicum MN110 were grown in growth chambers under 400 or $800{\mu}l{\cdot}l^{-1}$ atmospheric $CO_2$ and harvested at 25, 28, 32, and 35 DAT to examine the effect of $CO_2$ enrichment on phosphorus accumulation, uptake, and utilization efficiency during vegetative growth. Phosphorus concentration in leaf was lower in high $CO_2$ plant by 47% at 25 DAT and 34% at 35 DAT than those in the control plant but phosphorus concentrations in stem, root and nodule were not affected by $CO_2$ enrichment. Total phosphorus accumulation increased 3.9-fold in high $CO_2$ plant and 3.2-fold in the control plant between 25 and 35 DAT. Elevated $CO_2$ caused a decrease in the whole plant phosphorus concentration by 35%, which was due almost entirely to a decrease in the phosphorus concentration of leaves. $CO_2$ enrichment increased phosphorus utilization efficiency in the whole plant by 70% during the experimental period. Plants exposed to high $CO_2$ had larger root systems than under ambient $CO_2$, but high $CO_2$ plants had lower P-uptake efficiency. Averaged over four harvests, plants at high $CO_2$ had 38% larger root mass that was more than offset the 20% lower efficiency of P-uptake and accounted for increased phosphorus accumulation by high $CO_2$ plant. These results suggest that the reduced phosphorus concentration in soybean plant under $CO_2$ enrichment may be an acclimation response to high $CO_2$ concentration or enhanced starch accumulation, resulting in the plants to have a lower phosphorus requirement on a unit dry weight basis or a high phosphorus utilization efficiency under these conditions.

• 대한수의학회지
• /
• 제11권2호
• /
• pp.105-116
• /
• 1971

The effects of aconite root in rats and rabbits were studied following oral administration of the powder which was prepared by lyophilization of the decoction of the salted aconite roots. The $LD_{50}$ of the powder, the blood picture, total blood volume, uptake rate of ${42}^K$ and ${24}^Na$ in various organs, oxygen consumption, thyroid activity, and histopathological changes in various organs, were observed. The results obtained were as follows: 1. The $LD_{50}$ of the powder of decoction of the aconite root was 4.07g/kg of body weight in mice which is equivalent to approximately 40g/kg of the salted aconite roots. 2. The number of erythrocytes and leukocytes, hematocrit value, and the amount of hemoglobin in blood were increased in the rats administered daily dosages of 0.1, 0.5, and 1.0g/kg respectively. No significant differences were observed in the differential count of leukocytes. A slight tendency of hemoconcentration was recognized. 3. No changes in the erythrocyte volume, plasma volume and total blood volume were observed in the rats after administration of the powder for one, three, and six days. However, those were decreased in rats treated for ten days. 4. Generally, in various organs of rats the uptake rate of ${24}^Na$ showed a tendency of increasing but that of ${42}^K$ slowed a decreasing tendency. 5. The oxygen consumption was markedly decreased in rats administered the powder. 6. Iodine-131 uptake of thyroid gland was markedly decreased in the rabbits following administration of the powder. 7. In rabbits administered 0.5g/kg for 20 days, fatty changes of hepatic cells, cloudy swelling of the epithelial cells of proximal convoluted tubules of the kidney and the dilation of splenic sinuses were observed, however, milder changes were found in rabbits treated with 0.1g/kg for the same period.

• 한국토양비료학회지
• /
• 제38권4호
• /
• pp.173-179
• /
• 2005

Biosolid 처리는 옥수수의 생장을 촉진시켰으며 중금속 흡수 또한 현저히 증가시켰다. 특히 다른 biosolid와 비교하여 Nu-earth 처리에서 옥수수 지상부의 Cd과 Zn의 흡수가 많은 것으로 나타났다. 옥수수의 중금속 흡수는 biosolid 자체의 중금속 함량과 밀접하게 관련되었는데, 크롬과 납의 흡수는 그 중 상관관계가 가장 낮았다. 근권의 유기산은 주로 lactic acid, acetic acid, propionic acid, butyric acid 및 oxalic acid 인 것으로 나타났다. 그 외 glutaric acid와 succinic acid, pyruvic acid 및 tartaric acid도 일부 발견되었다. Biosolid를 처리한 경우에는 butyric acid가 가장 많았으며 처리하지 않은 경우에는 acetic acid가 가장 많았다.

• The Korean Journal of Ecology
• /
• 제26권4호
• /
• pp.165-172
• /
• 2003

The objectives of this study were to examine the physiological responses to ozone and to measure ozone uptake rates of Betula species exposed to relatively high concentration of pollutants. At the end of the growing season, photosynthesis, pigments contents, antioxidants (SOD and GR) and ozone uptake rates were measured or estimated at the leaves of five Betula species (Betula costata, B. davurica, B. platyphylla var. japonica, B. schmidtii and B. ermanii) exposed to 100ppb ozone concentration. On the termination of the experiment, growth effects were determined by measuring leaf area and dry weights of leaf, stem and root. Ozone treatment showed the significant reduction the leaf area and dry weight of four Betula species, except for B. ermanii. Shoot / root (SR) ratio of five species represented two different types. SR ratio of B. costata and B. davurica were lower than control, in contrast, SR ratio of B. platyphylla var. japonica, B. schimidtii and B. emani, were higher than that of control. The photosynthetic responses of five species were different in responses to ozone exposure. Four species, except for B. emanii, maintained or increased the stomatal conductance, but B. emanii decreased both stomatal conductance and photosynthesis. SOD activities of five species decreased by the ozone exposure, especially B. ermanii showed the largest reduction, GR activities of B. platyphylla var. japonica and B. schmidtii increased, B. costata and B. emanii decreased. Instantaneous ozone uptake rate was the highest at the leaves of B. ermanii and B. costata, ozone uptake per seedling was the highest at the leaf of B. schmidtii and B. emanii. It was concluded that B. costata, B. davurica and B. platyphylla var. japonica, appeared the growth reduction and visible ozone injury, were sensitive species to ozone, and B. schmidtii with the increased antioxidant activity and B. ermanii without the growth reduction were relatively resistant species to high ozone concentration at the early growing stage.

• 한국작물학회지
• /
• 제48권5호
• /
• pp.361-368
• /
• 2003

The responses of five varieties and three cultivars of pea (Pisum sativum) to Rhizobium inoculation on nodulation, growth, nitrogenase activity, dry matter production and N uptake were investigated. The pea varieties were IPSA Motorshuti-l, IPSA Motorshuti-2, IPSA Motorshuti-3, BARI Motorshuti-l, BARI Motorshuti-2 and the cultivars were 063, Local small and Local white. Fifty percent seeds of each pea variety/cultivar were inoculated with a mixture of Rhizobium inoculants at rate of 15g/kg seed and the remaining fifty percent seeds were kept uninoculated. The plants inoculated with Rhizobium inoculant significantly increased nodulation, growth, nitrogenase activity, dry matter production and N uptake. Among the varieties/cultivars, BARI Motorshuti-l performed best in almost all parameters including nitrogenase activity of root nodule bacteria of the crop. There were positive correlations among the number and dry weight of nodules (r=$0.987^{**}$, $0.909^{**}$), nitrogenase activity of root nodule bacteria (r=$0.944^{**}$, $0.882^{**}$), dry weight of shoot (r=$0.787^{**}$, $0.952^{**}$), N content (r=$0.594^{**}$, $0.605^{**}$) and N uptake (r=$0.784^{**}$, $0.922^{**}$) by shoot both at flowering and pod filling stages of the crop, respectively. It was concluded that BARI Motorshuti-l in symbiotic association with Rhizobium inoculant performed best in recording nitrogenase activity, dry matter production and N uptake by pea.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.35-35
• /
• 2017

How do plants take up water from soils especially when water is scarce in soils? Plants have a strategy to respond to water deficit to manage water necessary for their survival and growth. Plants regulate water transport inside them. Water flows inside the plant via (i) apoplastic pathway including xylem vessel and cell wall and (ii) cell-to-cell pathway including water channels sitting in cell membrane (aquaporins). Water transport across the root and leaf is explained by a composite transport model including those pathways. Modification of the components in those pathways to change their hydraulic conductivity can regulate water uptake and management. Apoplastic barrier is modified by producing Casparian band and suberin lamellae. These structures contain suberin known to be hydrophobic. Barley roots with more suberin content from the apoplast showed lower root hydraulic conductivity. Root hydraulic conductivity was measured by a root pressure probe. Plant root builds apoplastic barrier to prevent water loss into dry soil. Water transport in plant is also regulated in the cell-to-cell pathway via aquaporin, which has received a great attention after its discovery in early 1990s. Aquaporins in plants are known to open or close to regulate water transport in response to biotic and/or abiotic stresses including water deficit. Aquaporins in a corn leaf were opened by illumination in the beginning, however, closed in response to the following leaf water potential decrease. The evidence was provided by cell hydraulic conductivity measurement using a cell pressure probe. Changing the hydraulic conductivity of plant organ such as root and leaf has an impact not only on the speed of water transport across the plant but also on the water potential inside the plant, which means plant water uptake pattern from soil could be differentiated. This was demonstrated by a computer simulation with 3-D root structure having root hydraulic conductivity information and soil. The model study indicated that the root hydraulic conductivity plays an important role to determine the water uptake from soil with suboptimal water, although soil hydraulic conductivity also interplayed.