Photoinhibition in <i>Vitis californica</i>

Gamon, John A.; Pearcy, Robert W.

doi:10.1104/pp.92.2.487

Cited by 62 publications

(8 citation statements)

References 17 publications

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“…1B). Leaf temperature increases cause increased susceptibility to photoinhibition (Gamon and Pearcy, 1990). Similarly, decreases in the F v /F m value in the 0% shade treatment were probably dependent on PPFD levels associated with high temperatures.…”

Section: Resultsmentioning

confidence: 85%

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Rhie¹,

Lee²,

Jung³

et al. 2014

HST

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Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net CO2 assimilation rates and Fv/Fm values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. Fv/Fm, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

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Section: Resultsmentioning

confidence: 85%

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Rhie¹,

Lee²,

Jung³

et al. 2014

HST

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“…High PFD (> 1000 /imol m~^ s~') had the opposite effect, enhancing the damage of PSII by heat (Fig. 8), These interactive effects of high temperatures and high PFD could well limit carbon gain in wild H. arbutifoUa plants, as was suggested for the California wild grape (Gamon & Pearcy 1990a),…”

Section: Thermal Tolerance Pfd and Water Regimementioning

confidence: 71%

Interactions between water stress, sun‐shade acclimation, heat tolerance and photoinhibition in the sclerophyll Heteromeles arbutifolia

Valladares¹,

Pearcy²

1997

Plant Cell & Environment

362

263

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Gas exchange and chlorophyll fluorescence techniques were used to evaluate the acclimation capacity of the schlerophyll shrub Heteromeles arbutifolia M. Roem. to the multiple co-occurring summer stresses of the California chaparral. We examined the influence of water, heat and high light stresses on the carhon gain and survival of sun and shade seedlings via a factorial experiment involving a slow drying cycle applied to plants grown outdoors during the summer. The photochemical efficiency of PSII exhibited a diurnal, transient decrease (AF/F^') and a chronic decrease or photoinhibition (FJFj^) in plants exposed to full sunlight. Water stress enhanced both transient decreases of AFIF^' and photoinhibition. Effects of decreased AF/F^^' and F,^/F^ on carbon gain were observed only in well-watered plants since in waterstressed plants they were overidden by stomatal closure. Reductions in photochemical efficiency and stomatal conductance were observed in all plants exposed to full sunlight, even in those that were well-watered. This suggested that H. arbutifolia sacrificed carbon gain for water conservation and photoprotection (both structurally via sboot architecture and physiologically via down-regulation) and that this response was triggered by a hot and dry atmosphere together with high PFD, before severe water, heat or high PFD stresses occur. We found fast adaptive adjustments of the thermal stability of PSII (diurnal changes) and a superimposed long-term acclimation (days to weeks) to high leaf temperatures. Water stress enhanced resistance of PSII to high temperatures both in the dark and over a wide range of PFD. Low PFD protected photochemical activity against inactivation by heat while high PFD exacerbated damage of PSII by heat. The greater interception of radiation by horizontally restrained leaves relative to the steep leaves of sun-acclimated plants caused photoinhibition and increased leaf temperature. When transpirational cooling was decreased by water stress, leaf temperature surpassed the limits of chloroplast thermostability. The remarkable acclimation of water-stressed Key-words: Heteromeles arbutifolia., heat stress; interaction between stresses; leaf angle; photoinhibition; photosynthesis; sclerophyll; sun-shade acclimation; thermal stability of photosystem II; transpiration cooling; water stress.Abbreviations: A, net CO2 assimilation rate; FJF^, photochemical efficiency of PSII (dark adapted leaves); AF/F^', photochemical efficiency of PSII in the light; g^, stomatal conductance to water vapour; PFD, photosynthetic photon flux density; PSII, photosystem II; T^., critical temperature for heat-induced fluorescence rise; Tp, temperature of heatinduced peak fluorescence; % water potential.

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“…The maximum photochemical efficiency of PSII is directly proportional to the ratio of Fv/Fm of dark-adapted tissue (8). Induction of fluorescence emission was measured in situ using a portable fluorescence meter (Plant Stress Meter; Biomonitor, Charleston, SC) on 10 leaves per cultivar per treatment over a 3-d period during the afternoon (1300-1600 h) 1 The concentration of methanol-extractable UV-B-absorbing compounds (primarily flavonoids) was determined at the time of harvest for each cultivar and treatment.…”

Section: Seedsmentioning

confidence: 99%

CO₂ Enhancement of Growth and Photosynthesis in Rice (Oryza sativa)

Ziska¹,

Teramura²

1992

Plant Physiol.

128

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Two cultivars of rice (Oryza sativa L.) IR-36 and Fujiyama-5 were grown at ambient (360 microbars) and elevated CO2 (660 microbars) from germination through reproduction in unshaded greenhouses at the Duke University Phytotron. Growth at elevated CO2 resulted in significant decreases in nighttime respiration and increases in photosynthesis, total biomass, and yield for both cultivars. However, in plants exposed to simultaneous increases in CO2 and ultraviolet-B (UV-B) radiation, CO2 enhancement effects on respiration, photosynthesis, and biomass were eliminated in IR-36 and significantly reduced in Fujiyama-5. UV-B radiation simulated a 25% depletion in stratospheric ozone at Durham, North Carolina. Analysis of the response of CO2 uptake to intemal CO2 concentration at light saturation suggested that, for IR-36, the predominant limitation to photosynthesis with increased UV-B radiation was the capacity for regeneration of ribulose bisphosphate (RuBP), whereas for Fujiyama-5 the primary photosynthetic decrease appeared to be related to a decline in apparent carboxylation efficiency. Changes in the RuBP regeneration limitation in IR-36 were consistent with damage to the photochemical efficiency of photosystem 11 as estimated from the ratio of variable to maximum chlorophyll fluorescence. Little change in RuBP regeneration and photochemistry was evident in cultivar Fujiyama-5, however. The degree of sensitivity of photochemical reactions with increased UV-B radiation appeared to be related to leaf production of UV-B-absorbing compounds. Fujiyama-5 had a higher concentration of these compounds than IR-36 in all environments, and the production of these compounds in Fujiyama-5 was stimulated by UV-B fluence. Results from this study suggest that in rice alterations in growth or photosynthesis as a result of enhanced CO2 may be eliminated or reduced if UV-B radiation continues to increase. ' (13).In addition to CO2, CFCs, CH4, and N20 are also increasing with industrialization. The increase of these trace gases is expected to deplete the stratospheric ozone column with a subsequent increase in the amount of solar UV-B radiation reaching the earth (4, 24). Although UV-B radiation represents only a small proportion of the total electromagnetic spectrum, UV-B radiation has a disproportionally large photobiological effect, primarily due to its absorption by proteins and nucleic acids (9). Given the long atmospheric lifetime of the chlorine species (approximately 100 years) and the continued use of CFCs in manufacturing by many countries, the extent of stratospheric ozone depletion is difficult to predict. Recent measurements from the National Aeronautics and Space Administration, in fact, indicate that stratospheric ozone depletion over temperate latitudes is increasing at twice the predicted rate (1). In contrast to CO2, increased UV-B radiation has been shown to reduce growth and photosynthesis in a number of cultivated and native plant species (24,27

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Photoinhibition in Vitis californica

Cited by 62 publications

References 17 publications

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Interactions between water stress, sun‐shade acclimation, heat tolerance and photoinhibition in the sclerophyll Heteromeles arbutifolia

CO₂ Enhancement of Growth and Photosynthesis in Rice (Oryza sativa)

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Photoinhibition in Vitis californica

Cited by 62 publications

References 17 publications

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

Interactions between water stress, sun‐shade acclimation, heat tolerance and photoinhibition in the sclerophyll Heteromeles arbutifolia

CO2 Enhancement of Growth and Photosynthesis in Rice (Oryza sativa)

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Product

Resources

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CO₂ Enhancement of Growth and Photosynthesis in Rice (Oryza sativa)