• 한국작물학회지
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• 제26권1호
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• pp.45-50
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• 1981

Diurnal changes in leaf stomatal resistances were measured on leaf positions and both surfaces to investigate the stomatal response to irradiance in wheat, var. Chokwang and barley, var. Dongbori 1. Stomatal frequency and size were also determined to explain the control mechanism of gas exchanges in two species. The leaf diffusive resistances of two species decreased, as the sun rose, to minimum at 10 to 11 o'clock a.m. and increased gradually in the afternoon, even faster at sunset. As the adaxial irradiance increased, stomatal resistances decreased sensitively in the range of 30uEm$^{-2}$ㆍsec$^{-1}$ to 150uEm$^{-2}$ㆍsec$^{-1}$ quantum flux density. The stomatal opening of the abaxial surface began at lower irradiance and was completed earlier than the adaxial surface. The adaxial irradiances decreased in order of leaf position, flag, the 2nd, the 3rd leaf, and the stomatal resistances increased in the same order. Even under the same irradiance, the stomatal resistance of lower leaves were higher than those of upper leaves. The stomatal frequencies of lower leaves were less, but the stomatal size was greater than those of upper leaves. Consequently, the relative leaf area occupied by stomatal pores were constant among leaf positions in two species.

• 한국환경과학회지
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• 제6권2호
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• pp.125-131
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• 1997

The mechanism of stomatal closing in response to $O_2$ was indirectly investigated by using $H_2O_2$ which is the intermediate product of $O_2$ metabolites. Stomata in epidermal strips close in response to $H_2O_2$. The effect of $H_2O_2$ on stomatal closing was dependent on the concentration of $H_2O_2$. 10 ppm $H_2O_2$ showed a clear effect on stomatal closing and 1000 ppm $H_2O_2$ induced complete stomatal closing after the treatment of 3 hours. Stomatal closing by $H_2O_2$ in intact leaf was also observed by measuring the diffusion resistance with porometer. It was found that the stomatal closing by $H_2O_2$ was not mediated by $Ca^{2+}$, and that was a different result observed in stomatal closing by water stress. Reversely, $Ca^{2+}$ showed a great inhibition on stomatal closing. The leakage of K+ in epidermal strips was doubled in response to $H_2O_2$ when it was campared to the control. 10 ppm $H_2O_2$ decreased photosynthetic activity. Fv/Fm representing the activity of Photosystem II was reduced about 4 % in 10 ppm $H_2O_2$ and 8 % in 100 ppm $H_2O_2$ In the treatment of 1.5 hour. However, stomatal closing by 10 ppm $H_2O_2$ was reduced about 56 %. According1y, it can be suggested that stomatal closing by $H_2O_2$ is related with the decrease of photosynthetic activity, but it was chiefly induced by the change of the membrane permeability. Key words Commelina communis, stomatal closing, $H_2O_2$, $Ca^{2+}$, photosynthesis.

• Animal cells and systems
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• 제4권4호
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• pp.337-340
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• 2000

The photosynthetic and stomatal responses of several woody plants (Powlonia coreana, Firmiana simplex, Quercus acutissima Q. variabilis and Q. serrata) to SO$_2$ were investigated in order to understand their ecophysiological tolerance to $SO_2$ Of the plants, P, coreana showed the largest reduction in its photosynthesis in response to exposure of 0.4 ppm $SO_2$ for 20 h. Fumigation of 0.7 ppm $SO_2$ for 20 h caused complete leaf necrosis of P. coreana and f simplex, which made them unavailable for the measurement of photosynthesis. Q. variabilis exhibited the smallest reduction in photosynthesis following exposure of 0.7 ppm $SO_2$ for 20 h. Both stomatal- and non-stomatal inhibition of the plants by $SO_2$ were determined according to equations by lkeda et at. (1992). When exposed to 0.4 ppm $SO_2$ for 20 h, F. simplex and P. coreana showed the lowest stomatal and non-stomatal inhibition, respectively, while Q. variabilis and Q. serrata exhibited the lowest stomatal and non-stomatal inhibition, respectively, in response to 0.7 ppm $SO_2$ for 20 h. The data are discussed with regard to resistance mechanisms of other plants to $SO_2$ exposure and implications for restoration of declined Korean forests.

• The Korean Journal of Ecology
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• 제20권2호
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• pp.83-94
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• 1997

Stomatal closing by ozone and water stress could reduce further ozone injury by inhibition of ozone influx to the tissue. Direct effect of ozone on stomata can be explained from two aspects which are a stimulation of stomatal closing and an inhibition of stomatal opening. An increase of $Ca^{2+}$ influx into cytoplasm by ozone could stimulate potassium efflux ion channel and inhibits inward potassium ion channels. By this mechanism ozone could induce stomatal closing. On the other hand, ozone could inhibit stomatal opening by affecting the activity of $H^{+}$ dependent ATPase of the membrane in guard cells. This would inhibit proton efflux which precede stomatal opening. It is also possible that ozone could reduce the activity of photosynthesis in guard cells which lead to affect the production of osmotically active sugars and energy. Indirect effect of ozone to stomata is through the effect of $CO_2$ elevation as a result of damage of the photozynthetic machinery. This indirect effect is slower than the direct effect.

• 한국작물학회지
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• 제29권4호
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• pp.307-314
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• 1984

소맥 품종들에 대한 기공수의 품종간 차이, 엽각부위의 기공분석 및 기공수와 출수기, 간장및 타 광합성 관련형질들과의 관계를 구명코져 조광외 100품종을 공시 조사하였던 바 그 결과는 다음과 같다. 1. 지엽표면의 기공수는 최저 51(/$ extrm{mm}^2$), 최고90, 이면의 최저는 35, 최고는 65개로서 표면은 이면비해 1.5배가 많았으며, 가장 빈도가 높은 것은 기공수가 표면은 61~75, 이면은 41~50개인 품종들이었다. 2. 기공의 크기는 표면은 38.5~46.6$\mu$, 이면은39.4$\mu$48.0$\mu$으로 이면의 기공이 다소컸으며 기공수와 기공의 크기 간에는 표면 -0.63＊＊, 이면 -0.48＊의 상관이 인정되었다. 3. 상위엽의 기공수는 하위엽보다 많고 각 분얼 동신엽의 기공수는 지엽은 고위분얼이 그 하위엽에서는 저위분얼에서 발생한 엽에서 많아지는 경향이었다. 4. 동일엽신내에서는 표면은 선단부나 중앙부가 많고 기부가 적은 반면 이면은 반대의 경향을 나타내었다. 5. 지엽 및 제2엽의 엽초에도 기공수는 상당히 존재하여 제3엽이나 제4엽이면의 기공수보다도 많았다. 6. 지엽표면의 기공수가 많은 품종은 타엽신이나 엽초에도 많았다. 7. 지엽표면의 기공수와 간장, 출수기와는 각각 0.53＊, 0.51＊의 상관이 있었고 엽면적당 건물중(SLW)과는 -0.48＊, 엽록소함량 0.53＊, 엽면적 -0.59＊＊, 기공개도와는 -0.53＊ 의 상관이 인정되었으며, 엽맥수와는 상관이 인정되지 않았다. 따라서 기공수가 많은 품종은 간장이 크고, 출수기는 늦어지는 경향이며, 엽유의 두께나 엽면적은 작고 엽록소함량은 높아지는 경향이었다.

• 한국환경과학회지
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• 제15권12호
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• pp.1109-1117
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• 2006

To investigate the influence of the mesophyll cells on stomatal opening in response to white light, the segments of isolated epidermis were transferred on partly exposed mesophyll cells of a leaf and stomatal apertures were measured. Transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused a marked increase on stomatal apertures while stomata in isolated epidermis incubated in MES buffer hardly opened. Mesophyll infiltration with photosynthetic inhibitors (DCMU, DCCD, $NaN_3$) was performed to elucidate the correlation between stomatal apertures and the degree of photosynthetic activity. It was found that transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused an increase of stomatal apertures depending on the degree of photosynthetic activities. In $NaN_3$ infiltrated leaf discs, transferring the fresh isolated epidermis on partly exposed mesophyll cells of a leaf showed no significant effect, but a slight increase on stomatal apertures. Isolated epidermis alone did not respond to the light properly, but if it was closely contacted with mesophyil cells, the stomata regained the ability of the light response. Therefore, it could be suggested that stomatai apertures were related with the degree of photosynthetic activity in the mesophyll cells.

• Journal of Plant Biology
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• 제30권1호
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• pp.21-30
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• 1987

The effects of abscisic acid(ABA) spraying for 12 weeks on the stomatal types and frequencies of O. malacophyllus leaves were summarized as follows. ABA inhibited the growth of O. malacophyllus. The prominent effect of ABA on the epidermal structure was the promotion of senescence such as thickness of cell walls, smooth sinuosity of cell walls, and large size of epidermal cells. The stomatal frequency was decreased to 23% by 10$\mu\textrm{g}$ ml-1 ABA and to 48% by 100$\mu\textrm{g}$ml-1, and also the stomatal size was more or less smaller than that of control. The developing secondary stomatal mother cell was not found in both 10 and 100$\mu\textrm{g}$ml-1ABA, but the arrested secondary stomatal mother cell was rarely found in 10$\mu\textrm{g}$ ml-1 ABA. The formation of normal stomatal types such as helico-eumesogenous and aniso-eumesogenous was found in both 10 and 100 $\mu\textrm{g}$ ml-1 ABA asin well as control. Also nine abnormal stomatal types were found, and the frequencies were promoted to 6% by 10 $\mu\textrm{g}$ ml-1 ABA and to 17% by 100 $\mu\textrm{g}$ ml-1 ABA. Among these abnomal stomata, four types such as aborted stomata, single-aborted guard cells, arrested stomata, and modified stomatal complexes were found in control as well as in 10 and 100 $\mu\textrm{g}$ ml-1 ABA, but five types such as wrenched stomata, unequal stomata, wavy guard cells, guard cells overlapped by guard cells, and dissolved cell wall stomata were found in both 10 and 100 $\mu\textrm{g}$ ml-1ABA. The modified stomata complexes were abnormal stomatal types which were newly found and also were varied in types.

• 한국작물학회지
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• 제40권2호
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• pp.125-132
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• 1995

유형이 다른 품종들간에 기공밀도와 기체확산저항의 차이와 광합성 속도에 미치는 영향 등을 비교 검토한 바 일반적으로 Indica 품종의 기공밀도가 Japonica 품종보다 컸으나 기체확산은 작았다. Indica 품종과 Japonica 품종간의 교잡을 통하여 육성한 품종들의 기공밀도와 기체확산 저항은 중간가를 나타냈다. 기공밀도와 기체확산저항 광합성 속도 간에는 현저한 정의 상관을 보였지만 특수엽중과는 현저한 질의 상관을 보였고, 단엽면적과의 상관관계는 현저하지 않았다. Indica 품종과 Japonica품종간의 교잡을 통하여 Indica 품종의 기공밀도가 크고 기체확산저항이 낮은 특성과 Japonica 품종의 특수 엽중이 큰 특성을 결합할 수 있다면 광합성 속도를 더욱 높일 수 있으리라 추측된다.

• 한국약용작물학회지
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• 제10권2호
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• pp.82-87
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• 2002

차광 및 광 강도별 맥문동의 광합성속도, 기공전도도 및 증산작용과 그 관련형질간의 상호연관성을 구명하였던 바는 다음과 같다. 맥문동의 광합성속도는 광 강도가 증가함에 따라 증가하였고 PAR $700-1000{\mu}mol/m^2/s$에서 최고치를 나타내었으며 차광에 의해 증가되는 경향이었다. 기공전도도는 광 강도가 증가함에 따라 증가되었고, 광합성속도, 증산작용 및 기공전도도의 일변화는 비슷한 경향의 양상을 띄었다. 광합성속도와 기공전도도와의 관계는 1차직선회귀관계로 고도의 정(正)의 상관이 인정되었으나 대조구와 차광구가 각각 다른 1차회귀직선을 보여 동일한 기공전도도에서 차광구의 광합성속도가 대조구보다 높은 경향으로 나타났다. 증산작용과 기공전도도 및 광합성속도와 증산작용의 관계는 양자간에 모두 1차회귀식의 정(正)의 상관관계가 인정되었다.

• 아시안잔디학회지
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• 제11권1호
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• pp.23-31
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• 1997

The K+ and Na+ contents in the guard cells of Agave which had a characteristic of CAM plant were measured by using "Rolling technique". That results were correspond with the change of the stomatal aperture width. That is to say, stomatal movement of Agave is due to the change of K+and Na+ concentration in the guard cells. As Agave which was used in this experiment showed two peaks of which one was at 3 hour and the other was at 24 hour in stomatal aperture width, it was seemed that Agave had both characteristics of CAM and $C_3$pattern.