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  • Title/Summary/Keyword: stomatal

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Responses of Quercus spp. to SO2 (SO2에 대한 참나무속 식물의 반응)

  • 이창석;배정오
    • Journal of Korean Society for Atmospheric Environment
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    • v.7 no.3
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    • pp.219-226
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    • 1991
  • Results from study on physiological responses to SO2 of Quercus spp. selected for restoration of vegetation damaged by air pollution in the field study were as follows. Tolerance of Quercus aliena, Q. acutissima and Q. mongolica used in this study to SO2 was higher in that order and tolerance of these plants to SO2 was high comparatively among trees composing of major forest vegetation of Korea including natural forests and plantations. Stomatal resistance of these plants was increased after exposure to SO2 and range of increase was different among species. From discrepancy between order of tolerance to SO2 and range of increase in stomatal resistance, we were estimated that resistance mechanisms of Quercus spp. were different among species as mechanism originated in avoidance and resistance, respectively. Water potential of plant leaves reduced after exposure to SO2, degree of reduction accorded with order of tolerance to SO2. Reduction of water potential of plants after exposure to SO2 was initiated before appearance of visible damage in plant leaves and water potential of plants exposed to SO2 of low concentration, in which plants were not showed viaible damage was also reduced.

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Effects of Ozone on Crops and Protective Effects of Ethylenediurea as an Anti-Oxidant

  • Yun, Myoung-Hui;Lee, Woong-Sang
    • The Korean Journal of Ecology
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    • v.22 no.2
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    • pp.79-83
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    • 1999
  • Phytotoxic effects of ozone and ethylenediurea (EDU) on soybean (Glycine max) and spinach (Spinacia oleracea) were observed by using open-top field chamber system (OTC). Gas exchange rates (photosynthesis. stomatal conductance and transpiration rates) of soybean plants were decreased by 20% to 30% by ambient ozone and resulted in 30% reduction of seed yields. In OTC. ambient ozone and 0.12 μl/l O3 decreased gas exchange rates of spinach by 25% to 40% and by 50%. respectively. The protective effect of EDU against ozone induced injury was obtained at 100 mg/l on soybean. and at 250 mg/l on spinach, respectively. The excessive application of EDU. however. inhibited photosynthesis. transpiration. and stomatal conductance without any specific visible damage.

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Effect of photoperiod and light intensity on in vitro propagation of Alocasia amazonica

  • Jo, Eun-A.;Tewari, Rajesh Kumar;Hahn, Eun-Joo;Paek, Kee-Yoeup
    • Plant Biotechnology Reports
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    • v.2 no.3
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    • pp.207-212
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    • 2008
  • Plantlets of Alocasia amazonica regenerated under a photon flux density (PFD) of 15 or 30μmolm2s1 showed better growth and development than those grown under higher PFDs. While chlorophyll a and chlorophyll b decreased, the number of stomata increased with increasing PFD. Photoperiods also affected plantlet growth and stomatal development. Highest growth was observed for the short photoperiod (8/16 h) and for equinoctial (12/12 h) light and dark periods. Very few stomata developed in the leaves of plantlets grown under a short photoperiod (8/16 h) and the number of stomata increased with increasing light period. In conclusion, both light intensity and photoperiod independently affect growth of A. amazonica and development of stomata, depending on the intensity and duration of light treatment.

Ozone-environmental Effects on Gas Exchange and Growth of Hybrid Poplar (Populus trichocarpa × P. deltoides) Seedlings (오존 환경에 대한 잡종 포플러 묘목의 가스 교환과 생장에 관한 연구)

  • 우수영
    • The Korean Journal of Ecology
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    • v.20 no.4
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    • pp.239-244
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    • 1997
  • Hybrid poplar (Populus trichocarpa × P. deltoides) clones were fumigated with ozone. Fumigation was applied for 6 to 8 hours each day for approximately 3 months at ozone concentrations of 0.090 to 0.115 ppm using by open-top chambers. Growth and biomass of hybrid poplar seedlings were reduced by ozone exposure. Mean percentage of falling leaves in ozone-treated plant was 6 times higher than that of charcoal-filtered plant. Among physiological responses, rate of photosynthesis, stomatal conductance, transpiration and initial Rubisco activity were significantly lower in seedlings grown in ozone environment compared seedlings grown in charcoal-filtered air. All these physiological results supported that biochemical process to be a key feature to understand reduction in photosynthesis.

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Cuticle Micromorphology of Korean Gymnosperms I. Cycadaceae, Ginkgoaceae, Taxaceae and Cephalotaxaceae

  • Sung Soo Whang
    • Journal of Plant Biology
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    • v.38 no.2
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    • pp.181-193
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    • 1995
  • Cuticle micromorphology of four families of Korean gymnosperms, Cycadaceae, Ginkgoaceae, Taxaceae, and Cephalotaxaceae, were studied with scanning electron microscopy. The outer and inner features of abaxial and adaxial cuticles were described in details; the absent or present of Florin ring, orifice, trichome, and plug and their shape, the shape and periclinal and anticlinal wall sculpture of epidermal cells, the shape of cuticular flange of epidermal cell, guard cell, and subsidiary cell, the number of stomatal bands and rows, and stomatal apparatus including the shape of polar extension, number of subsidiary cells, the sculpture of guard cell and subsidiary cell. Most of these features have not been sufficiently substantiated by the previous reprots. Furthermore, all the species investigated showed distinctive cuticle morphology with morphological and taxonomical informations.

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Changes of Characteristics Related to Photosynthesis in Soybean Leaves Infected with Pseudomonas syringae pv. glycinea (세균성 점무늬병에 감염된 콩의 광합성 관련 특성 변화)

  • Ryu, Kyung-Yul;Heu, Hoon
    • Korean Journal Plant Pathology
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    • v.11 no.1
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    • pp.61-65
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    • 1995
  • Photosynthetic characteristics of soybean leaves infected with Pseudomonas syringae pv. glycinea were investigated for 8 days. The difference in photosynthesis rate between healthy and diseased soybean leaves decreased for 2 to 4 days after inoculation and then increased. In respiration rate, healthy and diseased leaves showed the same tendency as photosynthetic rate. The stomatal resistance increased following Pseudomonas syringae pv. glycinea infection. The total chlorophyll content of the infected leaf was less than that of the uninfected. Pseudomonas syringae pv. glycinea infection induced the malformation of stacked grana in chloroplast. Dry matter production declined after infection.

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Effects of Antioxidants on the Photosynsthesis and Carbohydrates/Saponin Contents in Panax ginseng Leaves (인삼잎의 광합성과 탄수화물.사포닌 함량에 미치는 항산화제의 효과)

  • 양덕조;김용해
    • Journal of Ginseng Research
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    • v.18 no.3
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    • pp.175-181
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    • 1994
  • We studied the folilar wiping effects of antioxidants (ascorbate, glutathione and sodium azide), which effectively inhibited the chlorophyll bleaching or completely recorved the early stage of photosynthesis of Panax ginseng C.A. Meyer, on photosynthesis, stomatal resistance, free sugar, starch, and total saponin contents of ginseng under the excess light intensity (45 kLux) during 6 days. Ascorbate and glutathione, endogenous antioxidant, recovered photosynehtsis and stomatal resistance, and reduced the photoinhibition by the excess light intensity (45 kLux) on free sugar, starch and total saponin contents. But sodium azide, exogenous 1O2 quencher, showed negative effect. Therefore, we assumed that carbohydrates and saponin metabolisms of ginseng by antioxidants (ascorbate, glutathione) were normal. For the reduction of inhibition by excess light in ginseng a program for the higher activation of antioxidants and antioxidative enzymes in ginseng leaf will be desirable. Key words Antioxidants, ascorbate, glutathione, Photoinhibition, ginseng.

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Characteristics of Photosynthesis with Growing Stages by different Shading Materials in Panax Ginseng C. A. Meyer (차광재료에 따른 생육시기별 인삼의 광합성작용의 특성)

  • Lee, Chung-Yeol
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.4
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    • pp.276-284
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    • 2007
  • To investigate the influence of shading materials with growing stages in Panax Ginseng C. A. Meyer, the diurnal change of photosynthesis, stomatal conductance, transpiration and its any correlation were measured. The net photosynthetic rate and stomatal conductance of ginseng were higher in the morning than in the broad day. The net photosynthetic rate was increased as the PAR (Photosynthetically Action Radiation) was increased and it was reached the maximum at the 200μmol/m2/s of PAR in overall leaves. Transpiration rate was increased in the afternoon compared to in the morning. The transpiration rate was higher in rain shelter shading plate than in polyethylene net. A linear equation was obtained between net photosynthetic rate and stomatal conductance in the morning. SPAD was higher in rain shelter shading plate than in polyethylene net through all growth stages. It may result from the decrease of growth progress. From investigating photosynthetic characteristics, we concluded that shading plate of rain shelter was more an efficient material to ginseng growth.

Physiological Responses of Calystegia soldanella under Drought Stress

  • Bae, Chae-Youn;Hwang, Jeong-Sook;Bae, Jeong-Jin;Choi, Sung-Chul;Lim, Sung-Hwan;Choi, Deok-Gyun;Kim, Jong-Guk;Choo, Yeon-Sik
    • Journal of Ecology and Environment
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    • v.36 no.4
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    • pp.255-265
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    • 2013
  • This study was conducted to determine the extent of drought resistance based on physiological responses of Calystegia soldanella under water deficit. In order to investigate the changes of plant growth, stomatal density, photosynthesis, chlorophyll fluorescence, the contents of chlorophyll and carotenoid, osmolality, total ion contents, the contents of carbohydrate and proline, C. soldanella was grown under well watered and drought stressed conditions for 12 days. In this study, water-deficit resulted in remarkable growth inhibition of C. soldanella. The effect of water-deficit on plant growth was associated with low osmotic potential of soil. On day 12 after drought treatment, dry weight, relative water contents, number and area of leaves and stem length were lower than those of control. The stomatal conductance and net photosynthetic rate were significantly reduced in water stressed plant to regulate inner water contents and CO2 exchange through the stomatal pore. Chlorophyll fluorescence and chlorophyll contents were not different in comparison with the control, indicating that the efficiency of photosystem II was not affected by drought stress. This results could be explained that water-deficit in C. soldanella limits the photosynthetic rate and reduces the plant's ability to convert energy to biomass. A significant increase in total ion contents and osmolality was observed on day 7 and day 12. Accumulation of proline in leaves is associated with the osmotic adjustment in C. soldanella to soil water-deficit. Consequently, this increase in osmolality in water stressed plant can be a result in the increase of ion contents and proline.

The Distribution of Cd2+ and its Physiological Toxicity in Commelina communis L. (닭의장풀 내 Cd2+의 분포와 생리적 독성)

  • 이준상
    • Korean Journal of Environmental Biology
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    • v.18 no.1
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    • pp.63-67
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    • 2000
  • The effect of Cd2+ on chlorophyll content, water potentials, ion transport, photosynthesis, stomatal apertures and Cd2+ accumulation of organs in Commelina communis was investigated. 3-weeks old Commelina. communis was transferred to and grown in Hoagland solution in the presence or absence of 5 mM Cd2+ for 4 days. Cd2+ was accumulated in all parts of the organs including leaves, roots and stem. The proximity from the root and the age of leaf were significant factors responsible for the distribution of cadmium. Most of Cd2+ was accumulated in the first leaf which was the nearest from the root. Cd2+) accumulation in the leaves led to significant reductions in a series of physiological metabolism. Cd2+ reduced total chlorophyll content up to 70%, and changed chlorophyll a/b ratio to 2. Cd2+ also reduced about 20% of water potential. The treatment of Cd2+ showed about 60% inhibition of photosynthetic activity when measured at various light intensity (100-1,000 μmol Em2s1). Similar effect was found in terms of stomatal conductance. Therefore, it could be concluded that the treatment of Cd2+ decrease or block various physiological activities. [Cadmium, Photosynthesis, Stomatal conductance].

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