• Mycobiology
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• 제36권1호
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• pp.24-27
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• 2008

This study was conducted to understand how osmotic potentials in Lentinula edodes tissues are related to water contents and how they change while a mushroom matures. Water content and osmotic potential of L. edodes mushroom tissues from log cultivation and sawdust cultivation were measured and the relationships were analyzed. Osmotic potentials in the tissues were exponentially proportional to their moisture contents and there were strain differences in the potentials. Strain 290 has lower osmotic potential than strain 302, in the tissues at the same water content. As the mushrooms mature, tissue water content maintained ca 94% in head tissues and ca 90% in gills, but significantly decreased from ca 90% to 82% in the stipe tissues. Osmotic potential changes were similar to the tissue water content changes as the mushrooms mature. While osmotic potentials maintained -0.25 to -0.45 MPa in head and gill tissues, the potentials greatly decreased from -0.65 to -1.33 MPa in stipe tissues. Our results show that osmotic potentials in L. edodes tissues are exponentially proportional to tissue water contents, that strains differ in osmotic potential related to water, and that stipe tissues can still have nutritional value when they mature.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.80-84
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• 2005

Many important properties in colloidal systems are usually determined by surface charge ($\zeta$-potential) of the contacted solid surface. In this study, $\zeta$-potential of glass $\mu$-channel was evaluated from the electro-osmotic velocity distribution. The electro-osmotic velocity inside a glass $\mu$-channel was measured using a micro-PIV velocity field measurement technique. This evaluation method is more simple and easy to approach, compared with the traditional streaming potential technique. The $\zeta$-potential in the glass $\mu$-channel was measured for two different mole NaCl solutions. The effect of an anion surfactant, sodium dodecyl sulphate (SDS), on the electro-osmotic velocity and $\zeta$-potential in the glass surface was also studied. In the range of $0\∼6$mM, the surfactant SDS was added to NaCl solution in four different mole concentrations. As a result, the addition of SDS increases $\zeta$-potential in the surface of the glass $\mu$-channel. The measured $\zeta$-potential was found to vary from-260 to-70mV. When negatively charged particles were used, the flow direction was opposite compared with that of neutral particles. The $\zeta$-potential has a positive sign for the negative particles.

• 대한기계학회논문집B
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• 제30권10호
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• pp.935-941
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• 2006

Many important properties in colloidal systems are usually determined by surface charge $({\zeta}-potential)$ of the contacted solid surface. In this study, ${\zeta}-potential$ of glass ${\mu}-channel$ was evaluated from the electro-osmotic velocity distribution. The electro-osmotic velocity inside a glass f-channel was measured using a micro-PIV velocity field measurement technique. This evaluation method is more simple and easy to approach, compared with the traditional streaming potential technique. The ${\zeta}-potential$ in the glass ${\mu}-channel$ was measured fur two different mole NaCl solutions. The effect of an anion surfactant, sodium dodecyl sulphate (SDS), on the electro-osmotic velocity and f-potential in the glass surface was also studied. In the range of $0{\sim}6mM$, the surfactant SDS was added to NaCl solution in few different mole concentrations. As a result, the addition of SDS increases ${\zeta}-potential$ in the surface of the glass ${\mu}-channel$. The measured $\zeta-potential$ was found to vary from -260 to -70mV. When negatively charged particles were used, the flow direction was opposite compared with that of neutral particles. The ${\zeta}-potential$ has a positive sign for the negative particles.

• 한국초지조사료학회지
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• 제20권2호
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• pp.77-84
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• 2000

Eight-week old perennial ryegrass (Lolium perenne L. cv. Reveille) plants were exposed to different NO3-concentrations or osmotic stress with NaCI. Previously labeled "N was chased during 14 days of non-labeled'NO3 feeding in order to investigate NO3 metabolism in relation to osmoregulation. The short termmeasurement of osmotic potential showed that the extemal concentration of Nos- had not great effect on theosmotic potential, but that osmotic adjustment was observed in NaCl-treated plants. Total uptake of NO 3 - waslargely increased by increasing supply level of NO3 while it was depressed by exposing to osmotic stress.Nitrate reduction increased to more than 29% by increasing extemal NO,- concentration from 1 mM to 10mM. When osmotically stressed with NaCI, nitrate reduction was depressed to about 37% as compared to thecontrol. The decrease in translocation of reduced N into leaves was also observed in NaCl exposed plants. Inthe medium exposed to 10 mM NO,., osmotic contribution of nitrate to cumulative osmotic potential wasdecreased, and it was osmotically compensated with soluble carbohydrate. When osmotically stressed withNaC1, the contribution of chloride was much higher than that of nitrate. The present data indicate that N03-in plant tissues, factually affected by the assimilation of this ion, plays an active role in osmotic regulation incorrelation with other osmotica such carbohydrate and chloride.(Key words : Nitrate metabolism, Osmotic stress, Nitrate supply level, Osmoregulation)ate supply level, Osmoregulation)

• 한국작물학회지
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• 제50권1호
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• pp.28-31
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• 2005

To identify salt-tolerance characteristics of corn seedling was treated in solution of 0, 50 and 100 mM NaCl of hydroponic cultivation. In photosynthesis of corn seedling, there was no large difference between 50mM and 0 mM NaCl solution, however, in 100 mM NaCl solution, the tolerance gradually decreased to $76\%,\;49\%,\;and\;31\%$ after one day, four days, and seven days, respectively, in comparison to 0 mM NaCl solution. Osmotic potential of corn in seedling period was significantly decreased with increasing saline level, however, free proline content in the plant on the ground was significantly increased with increasing saline level and with the lapse of time. In terms of correlation among major characteristics, there was a highly significant positive difference between osmotic pressure potential and photosynthesis, However, highly negative correlation was found between osmotic pressure potential and free proline content. In addition, it was expected that young seedling of corn with saline tolerance may be utilized in the transplantation in salt-accumulated land. Based on above-shown result, in terms of saline tolerance of Chalok-2 variety, growth suppression was serious with 100mM NaCl solution. However, growth was expected that seedling growth would be favorable under 50 mM NaCl solution.

• The Korean Journal of Ecology
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• 제24권4호
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• pp.223-226
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• 2001

The leaf water relations and photosynthetic rate during acute soil drying were compared in potgrown grapevine cultivars, Vitis vinifera cv. Chardonnay and V. vinifera cv. Riesling. Leaf water potential in Riesling decreased significantly from day 2 after water had been withheld, while in Chardonnay leaf water potential for the water-stressed plants was almost identical with that in well watered plants during the first 4 days. Higher stomatal conductance and photosynthetic rate in Chardonnay than Riesling were observed until day 3 after withholding water. Photosynthetic rate in water-stressed Chardonnay was not different from that in control plants until day 3 after withholding water, while that in water-stressed Riesling was reduced markedly from day 2. In Riesling, osmotic potential at turgor loss point was not changed irrespective of watering conditions. However, in Chardonnay osmotic potential at turgor loss point decreased more in the water stressed conditions than in well watered conditions. The osmotic adjustment in Chardonnay under water stress conditions must contribute to the maintenance of higher stomatal conductance and photosynthetic rate than those in Riesling for a significant period of the drying process. Though difference in stomatal conductance between the two cultivars was shown in the process of soil drying, stomatal conductance of both cultivars responded to vapor pressure difference between leaf and ambient air, rather than soil water status and leaf water potential.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.214-214
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• 2017

Seeds of Tomato (Lycopersicon esculentum Mill.) have demanded high quality because of their high cost of seed. The optimization of the seed priming techniques that have positive effect on fast and uniform germination becomes important at the commercial level. Several factors such as solution composition, osmotic potential, and treatment duration affect seed priming response. In this study, osmotic potentials of priming solution and germination characteristics of primed seed were investigated to clarify the effects different inorganic salt types and the duration. Tomato seeds were primed in osmotic solutions that were osmotic potential ranged -1.54 to -0.45 MPa in an aerated solution of PEG 8000 (17%, 22%, 27%), and inorganic salt solution of $KNO_3$, $Na_2SO_4$, and $K_2SO_4$ (100, 200, 300mM). The seeds were treated at $20^{\circ}C$ for 2, 4, and 6 days. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$. Four replications of 25 seeds per each treatments were placed in 10-cm petri dishes containing two filter papers and 3 ml of $dH_2O$ and incubated at $20^{\circ}C/30^{\circ}C$ and $15^{\circ}C$ and seedlings evaluated for abnormality after 14 days of incubation. Seed water potential (${\psi}$) was correlated with water potential of priming solution ($r^2=0.86$). Seeds primed in 100mM $KNO_3$ resulted the highest germination rate (GR, $63.9 %{\cdot}day^{-1}$) and lowest mean germination time (MGT, 2.0 days) comparing to untreated control ($23.9%{\cdot}day^{-1}$ of germination rate and 4.1 days of MGT) at $20/30^{\circ}C$, even though 96% of germination percentage were not different. Seeds primed in 100mM $KNO_3$ (${\psi}=-0.45MPa$) for 4 days showed ${\psi}=-0.38MPa$. Priming in $Na_2SO_4$, $K_2SO_4$, and PEG solution for 6 days improved MGT and GR, but not significantly than 4 days of treatment. Additionally, stepwise osmotic solution treatment with 100mM and 300mM concentration for 6 day did not showed differences with single treatment. In relation to osmotic potentials, identical osmotic potential in different inorganic salt solution showed different effect on germination characteristics.

• 한국작물학회지
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• 제26권2호
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• pp.157-166
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• 1981

본 시험은 대두 종자의 수분흡수 및 삼투압이 발아에 미치는 영향을 구명코저 수행되었다. Essex, Pickett, Bonus와 Wayne 4개품종이 공시되었고, 이들 품종들의 종자를 각각 소입 및 대입으로 분류하여 수분흡수를 측정하였다. 그 결과를 요약하면 다음과 같다. 1. 모든 수분조건에서 대두 종자의 수분흡수 능력은 종자의 크기 및 품종간의 유의적인 차를 보였다. Essex와 Pickett은 Bonus와 Wayne에 비해, 동일품종내에서 소입은 대입에 비해 수분흡수 능력이 우월하였다. 2. $25^{\circ}C$의 온도에서 대두 종자의 발아기간은 적당한 수분조건 및 -6bars의 토양수분 상태에서 2일, -15bars의 토양수분 조건에서는 5일로 지연되있고, Essex나 Pickett은 Wayne이나 Bonus에 비해, 그리고 소입종은 대입종에 비해 발아기간이 단축되었다. 3. 적당한 수분조건에서 발아초기에 대두 종자의 수분함량은 60.8%이였으며, 발아에 필요한 최소 종자의 수분함량은 -6bars에서 50.2%, -15bars에서 50.9% 이었다. 4. 발아기에 있어서 대두 종자의삼투압품종 및 침종시기에 따라 유의적인 변이를 보였으며, 4시간과 8시간 침종사이에서 급수한 증가를 보였다. 평균 삼투압은 4시간에 침종에서 -32.0bars, 발아초기에서 11.2bars의 범위를 나타냈다. 5. 초기 침종으로부터 발아초기 동안의 품종별 전체평균 삼투압을 보면 Bonus가 -19.4bars, Wayne이 -18.3bars, Essex가 -15.1bars, 그러고 pickett이 -13.2 bars 이었다. 6. 침종시간에 따른 초장의 길이와 삼투압간의 상관계수는 유의성이 없었으며, 이 결과는 대두 종자의 삼투압은 초기초장의 생장과 직접적인 관련이 없는 것으로 추정된다. 그러나 수분흡수와 삼투압간의 상관계수는 고도의 정의 유의성을 보였다(r=.98). Bonus나 Wayne에 비해 Pickett과 Essex는 높은삼투압을 보였으며, 이것은 수분흡수 시험결과와 일치하고 있다. 따라서 대두 종자의 삼투압은 건조상태에서 발아능력을 추정하는 하나의 지표가 되리라 생각한다.

• Macromolecular Research
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• 제17권10호
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• pp.763-769
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• 2009

A chromatographic method is used to measure interactions between dissimilar proteins in aqueous electrolyte solutions as a function of ionic strength, salt type, and pH. One protein is immobilized on the surface of the stationary phase, and the other is dissolved in electrolyte solution conditions flowing over that surface. The relative retention of proteins reflects the mean interactions between immobile and mobile proteins. The osmotic cross second virial coefficient calculated by assuming a proposed potential function shows that the interactions of unfavorable proteins depend on solution conditions, and the proposed model shows good agreement with the experimental data of the given systems.

• 한국환경과학회지
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• 제10권1호
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• pp.79-84
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• 2001

To assess resistance of transgenic tobacco plants which overexpress superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts to water stress, changes in leaf water potential, turgor potential, stomatal conductance and transpiration rate were measured. Leaf water potential in all plants remained high up to day 4 after withholding water but thereafter decreased markedly. In spite of a remarkable decrease in leaf water potential, some of transgenic plants maintained higher turgor potential compared with control plant on day 12. In particular, the transgenic plant expressing MnSOD showed an outstanding maintenance in turgor pressure by osmotic adjustment throughout the experiment, resulting in high stomatal conductance and transpiration rate. However, among transgenic plants, osmotic potential was reduced more effectively in multiple transformants such as the double transformant expressing both MnSOD and APX, and the triple transformant expressing CuznSOD, MnSOD and APX than single transformants. Consequently, further research is needed to get general agreement on the tolerance of transgenic plants to water stress at different growth stages for each transgenic plant.