scholarly journals Photosynthetic Parameters Show Specific Responses to Essential Mineral Deficiencies

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 996
Author(s):  
Miho Ohnishi ◽  
Riu Furutani ◽  
Takayuki Sohtome ◽  
Takeshi Suzuki ◽  
Shinya Wada ◽  
...  
Keyword(s):  
Electron Flux ◽  
Assimilation Efficiency ◽  
Primary Electron ◽  
Oxidation States ◽  
Photochemical Quenching ◽  
Photosynthetic Parameters ◽  
Mineral Deficiency ◽  
Primary Electron Acceptor ◽  
Relative Electron ◽  
Non Photochemical Quenching

In response to decreases in the assimilation efficiency of CO2, plants oxidize the reaction center chlorophyll (P700) of photosystem I (PSI) to suppress reactive oxygen species (ROS) production. In hydro-cultured sunflower leaves experiencing essential mineral deficiencies, we analyzed the following parameters that characterize PSI and PSII: (1) the reduction-oxidation states of P700 [Y(I), Y(NA), and Y(ND)]; (2) the relative electron flux in PSII [Y(II)]; (3) the reduction state of the primary electron acceptor in PSII, QA (1 − qL); and (4) the non-photochemical quenching of chlorophyll fluorescence (NPQ). Deficiency treatments for the minerals N, P, Mn, Mg, S, and Zn decreased Y(II) with an increase in the oxidized P700 [Y(ND)], while deficiencies for the minerals K, Fe, Ca, B, and Mo decreased Y(II) without an increase in Y(ND). During the induction of photosynthesis, the above parameters showed specific responses to each mineral. That is, we could diagnose the mineral deficiency and identify which mineral affected the photosynthesis parameters.

scholarly journals Relation of Photochemical Reflectance Indices Based on Different Wavelengths to the Parameters of Light Reactions in Photosystems I and II in Pea Plants

2020 ◽  
Vol 12 (8) ◽  
pp. 1312
Author(s):  
Ekaterina Sukhova ◽  
Vladimir Sukhov
Keyword(s):  
Remote Sensing ◽  
Pulse Amplitude ◽  
Ecological Monitoring ◽  
Photochemical Quenching ◽  
Photosynthetic Parameters ◽  
Pam Fluorometer ◽  
Physiological Processes ◽  
Non Photochemical Quenching ◽  
Induced Changes ◽  
Reflectance Indices

Measurement and analysis of the numerous reflectance indices of plants is an effective approach for the remote sensing of plant physiological processes in agriculture and ecological monitoring. A photochemical reflectance index (PRI) plays an important role in this kind of remote sensing because it can be related to early changes in photosynthetic processes under the action of stressors (excess light, changes in temperature, drought, etc.). In particular, we previously showed that light-induced changes in PRIs could be strongly related to the energy-dependent component of the non-photochemical quenching in photosystem II. The aim of the present work was to undertake comparative analysis of the efficiency of using light-induced changes in PRIs (ΔPRIs) based on different wavelengths for the estimation of the parameters of photosynthetic light reactions (including the parameters of photosystem I). Pea plants were used in the investigation; the photosynthetic parameters were measured using the pulse-amplitude-modulated (PAM) fluorometer Dual-PAM-100 and the intensities of the reflected light were measured using the spectrometer S100. The ΔPRIs were calculated as ΔPRI(band,570), where the band was 531 nm for the typical PRI and 515, 525, 535, 545, or 555 nm for modified PRIs; 570 nm was the reference wavelength for all PRIs. There were several important results: (1) ∆PRI(525,570), ∆PRI(531,570), ∆PRI(535,570), and ∆PRI(545,570) could be used for estimation of most of the photosynthetic parameters under light only or under dark only conditions. (2) The combination of dark and light conditions decreased the efficiency of ∆PRIs for the estimation of the photosynthetic parameters; ∆PRI(535,570) and ∆PRI(545,570) had maximal efficiency under these conditions. (3) ∆PRI(515,570) and ∆PRI(525,570) mainly included the slow-relaxing component of PRI; in contrast, ∆PRI(531,570), ∆PRI(535,570), ∆PRI(545,570), and ∆PRI(555,570) mainly included the fast-relaxing component of PRI. These components were probably caused by different mechanisms.

scholarly journals The role of coccoliths in protecting <i>Emiliania huxleyi</i> against stressful light and UV radiation

2016 ◽  
Vol 13 (16) ◽  
pp. 4637-4643 ◽  
Author(s):  
Juntian Xu ◽  
Lennart T. Bach ◽  
Kai G. Schulz ◽  
Wenyan Zhao ◽  
Kunshan Gao ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Uv Radiation ◽  
Growth Rates ◽  
Emiliania Huxleyi ◽  
Photochemical Quenching ◽  
Visible Radiation ◽  
Light Levels ◽  
Relative Electron ◽  
Non Photochemical Quenching

Abstract. Coccolithophores are a group of phytoplankton species which cover themselves with small scales (coccoliths) made of calcium carbonate (CaCO3). The reason why coccolithophores form these calcite platelets has been a matter of debate for decades but has remained elusive so far. One hypothesis is that they play a role in light or UV protection, especially in surface dwelling species like Emiliania huxleyi, which can tolerate exceptionally high levels of solar radiation. In this study, we tested this hypothesis by culturing a calcified and a naked strain under different light conditions with and without UV radiation. The coccoliths of E. huxleyi reduced the transmission of visible radiation (400–700 nm) by 7.5 %, that of UV-A (315–400 nm) by 14.1 % and that of UV-B (280–315 nm) by 18.4 %. Growth rates of the calcified strain (PML B92/11) were about 2 times higher than those of the naked strain (CCMP 2090) under indoor constant light levels in the absence of UV radiation. When exposed to outdoor conditions (fluctuating sunlight with UV radiation), growth rates of calcified cells were almost 3.5 times higher compared to naked cells. Furthermore, the relative electron transport rate was 114 % higher and non-photochemical quenching (NPQ) was 281 % higher in the calcified compared to the naked strain, implying higher energy transfer associated with higher NPQ in the presence of calcification. When exposed to natural solar radiation including UV radiation, the maximal quantum yield of photosystem II was only slightly reduced in the calcified strain but strongly reduced in the naked strain. Our results reveal an important role of coccoliths in mitigating light and UV stress in E. huxleyi.

scholarly journals Effects of Different Shading Rates on the Photosynthesis and Corm Weight of Konjac Plant

2019 ◽  
Vol 47 (3) ◽  
Author(s):  
Yaoguo QIN ◽  
Zesheng YAN ◽  
Honghui GU ◽  
Zhengxiang WANG ◽  
Xiong JIANG ◽  
...  
Keyword(s):  
Photosynthetic Efficiency ◽  
Daily Variation ◽  
Photochemical Efficiency ◽  
High Yield ◽  
Photochemical Quenching ◽  
Digital Object Identifier ◽  
Chlorophyll Fluorescence Parameters ◽  
Relative Electron ◽  
Comprehensive Comparison ◽  
Non Photochemical Quenching

To study the effects of shading level on the photosynthesis and corm weight of konjac plant, the chlorophyll fluorescence parameters, daily variation of relative electron transport rate (rETR), net photosynthetic rate (Pn), and corm weight of konjac plants under different treatments were measured and comparatively analyzed through covered cultivation of biennial seed corms with shade nets at different shading rates (0%, 50%, 70%, and 90%). The results showed that with the increase in shading rate, the maximum photochemical efficiency, potential activity, and non-photochemical quenching of photosystem Ⅱ (PSⅡ) of konjac leaves constantly increased, whereas the actual photosynthetic efficiency, rETR, and photochemical quenching of PSⅡ initially increased and then decreased. This result indicated that moderate shading could enhance the photosynthetic efficiency of konjac leaves. The daily variation of rETR in konjac plants under unshaded treatment showed a bimodal curve, whereas that under shaded treatment displayed a unimodal curve. The rETR of plants with 50% treatment and 70% treatment was gradually higher than that under unshaded treatment around noon. The moderate shading could increase the Pn of konjac leaves. The stomatal conductance and transpiration rate of the leaves under shaded treatment were significantly higher than those of the leaves under unshaded treatment. Shading could promote the growth of plants and increase corm weight. The comprehensive comparison shows that the konjac plants had strong photosynthetic capacity and high yield when the shading rate was 50%-70% for the area.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Influence of Low Light on the Growth and Development of Vallisneria natans Seedlings

2013 ◽  
Vol 295-298 ◽  
pp. 62-68 ◽  
Author(s):  
Qiang Li ◽  
Yun Cheng Xie
Keyword(s):  
Weight Ratio ◽  
Photochemical Quenching ◽  
Low Light ◽  
Vallisneria Natans ◽  
Relative Electron Transport Rate ◽  
Leaf Formation ◽  
Relative Electron ◽  
Macrophyte Growth ◽  
Non Photochemical Quenching ◽  
Photochemical Quantum Yield

To research influence of low light on macrophyte growth, seedlings of Vallisneria natans were transplanted into the waters with 5%, 1%, 0.5% and 0.1% full sunlights, respectively. The results show that germination rates are significantly inhibited with the experiment. In first 20 days leaf formation of new plants aren’t inhibited, and their leaf elongation are promoted. Since then, them of old plants and new plants are remarkably inhibited with the experiment. Though maximum photochemical quantum yield (Fv/Fm), relative electron transport rate (ETR) and non-photochemical quenching (NPQ) of old plants reduce significantly on low light conditions, but V. natans still hsa a certain degree of photoasynthetic capacity on the 80th day. Fresh weight ratio of roots and stems increase with decreasing light intensity. However, it exhibits an opposite trend for leaves. Thus, V. natans has a strong ability of low-light (≤1% full sunlight) tolerance.

scholarly journals EFFECT OF CHILLING STRESS ON THE PHOTOSYNTHETIC PERFORMANCE OF YOUNG PLANTS FROM TWO MAIZE (ZEA MAYS) HYBRIDS

2017 ◽  
Vol 5 ◽  
pp. 1118-1123 ◽  
Author(s):  
Rositsa Cholakova-Bimbalova ◽  
Andon Vassilev
Keyword(s):  
Lipid Peroxidation ◽  
Transition Period ◽  
Chilling Stress ◽  
Experimental Period ◽  
Photosynthetic Performance ◽  
Photochemical Quenching ◽  
Photosynthetic Parameters ◽  
Climate Conditions ◽  
Maize Plants ◽  
Non Photochemical Quenching

: In the climate conditions of Bulgaria, early stages of maize plants development often go under suboptimal temperatures. Chilling stress is known to cause different physiological disturbances in young maize plants during the transition period from heterotrophic to autotrophic nutrition. However, the effect of chilling may differ among maize hybrids. Photosynthetic performance could be a good indicator for the hybrid tolerance to chilling. The aim of our study was to evaluate the tolerance of young maize plants from two hybrids – the new Bulgarian hybrid - Kneza 307 and the hybrid P9528 using as criteria the changes in their photosynthetic performance.Plants at the third leaf stage were exposed for seven days to chilling stress. At the end of the experimental period, growth, leaf lipid peroxidation, and several photosynthetic parameters were measured. We found that chilling stress reduced the fresh mass accumulation, increased lipid peroxidation, diminished net photosynthetic rate and chlorophyll content, and enhanced non-photochemical quenching of chlorophyll fluorescence. Although the responses of both hybrids were similar, some specificity were observed and discussed.

scholarly journals Photosynthetic apparatus performance of tomato seedlings grown under various combinations of LED illumination

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249373
Author(s):  
Ahmed F. Yousef ◽  
Muhammad M. Ali ◽  
Hafiz M. Rizwan ◽  
Shehu Abubakar Tadda ◽  
Hazem M. Kalaji ◽  
...  
Keyword(s):  
Blue Light ◽  
Photosynthetic Apparatus ◽  
Photochemical Quenching ◽  
Future Research ◽  
Photosynthetic Parameters ◽  
Plant Responses ◽  
Light Sources ◽  
Fluorescence Measurement ◽  
Tomato Plants ◽  
Non Photochemical Quenching

It is already known that the process of photosynthesis depends on the quality and intensity of light. However, the influence of the new light sources recently used in horticulture, known as Light Emitting Diodes (LEDs), on this process is not yet fully understood. Chlorophyll a fluorescence measurement has been widely used as a rapid, reliable, and noninvasive tool to study the efficiency of the photosystem II (PSII) and to evaluate plant responses to various environmental factors, including light intensity and quality. In this work, we tested the responses of the tomato photosynthetic apparatus to different light spectral qualities. Our results showed that the best performance of the photosynthetic apparatus was observed under a mixture of red and blue light (R7:B3) or a mixture of red, green and blue light (R3:G2:B5). This was demonstrated by the increase in the effective photochemical quantum yield of PSII (Y[II]), photochemical quenching (qP) and electron transport rate (ETR). On the other hand, the mixture of red and blue light with a high proportion of blue light led to an increase in non-photochemical quenching (NPQ). Our results can be used to improve the production of tomato plants under artificial light conditions. However, since we found that the responses of the photosynthetic apparatus of tomato plants to a particular light regime were cultivar-dependent and there was a weak correlation between the growth and photosynthetic parameters tested in this work, special attention should be paid in future research.

scholarly journals Influence of Pulsed Electric Fields on Photosynthesis in Light/Dark-Acclimated Lettuce

Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 173
Author(s):  
Douyan Wang ◽  
Yu Hayashi ◽  
Takahiro Enoki ◽  
Kenta Nakahara ◽  
Tetsuya Arita ◽  
...  
Keyword(s):  
Electric Fields ◽  
Statistical Significance ◽  
Photochemical Quenching ◽  
Photosynthetic Parameters ◽  
Stress Reactions ◽  
Photosynthetic Response ◽  
Response Characteristics ◽  
Living Organisms ◽  
High Electric Fields ◽  
Non Photochemical Quenching

Recent years have seen numerous studies into how applying pulsed high electric fields (PEF) to living organisms induces various stress reactions. Plants produce glucose through photosynthesis and use this as a source of energy for living, yet there are few studies on the photosynthetic response characteristics when PEF is applied to growing plants. In this study, the photosynthetic response when electric fields of 10 to 100 V/mm were applied to light and dark-acclimated leaves of lettuce was measured by combined gas exchange and chlorophyll fluorescence, and the exposure time was kept constant at 500 s. The responses to PEF with regard to the photosynthetic parameters of electron transfer rate (ETR), non-photochemical quenching (NPQ), photosynthetic rate (A), and transpiration rate (E) were recorded during the experiment. Results showed that PEF can cause both the activation and deactivation of photosynthetic activity in lettuce, that there is an optimum value for activation, and that the application of excessive energy leads to inactivation. This study also found that stomata on both active and deactivated lettuce had been open to a greater extent than lettuce to which PEF had not been applied. All the results of statistical significance in this study were p < 0.05 and p < 0.01.

scholarly journals The role of coccoliths in protecting <i>Emiliania huxleyi</i> against stressful light and UV radiation

2016 ◽  
Author(s):  
Juntian Xu ◽  
Lennart T. Bach ◽  
Kai G. Schulz ◽  
Wenyan zhao ◽  
Kunshan Gao ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Uv Radiation ◽  
Growth Rates ◽  
Emiliania Huxleyi ◽  
Photochemical Quenching ◽  
Visible Radiation ◽  
Light Levels ◽  
Relative Electron ◽  
Non Photochemical Quenching

Abstract. Coccolithophores are a group of phytoplankton species which cover themselves with small scales (coccoliths) made of calcium carbonate (CaCO3). The reason why coccolithophores form these calcite platelets has been a matter of debate since decades but has remained elusive so far. One hypothesis is that they serve a role in light/UV protection, especially in surface dwelling species like Emiliania huxleyi which can tolerate exceptionally high levels of solar radiation. In this study, we tested this hypothesis by culturing a calcifying and a non-calcifying strain under different light conditions with and without UV radiation. The coccoliths of E. huxleyi reduced the transmission of visible radiation (400–700 nm) by 7.5 %, UV-A (315–400 nm) by 14.1 % and UVB (280–315 nm) by 18.4 %. Growth rates of the calcifying strain (PML B92/11) were about 2 times higher than those of the non-calcifying strain (CCMP 2090) under indoor constant light levels in the absence of UV radiation. When exposed to outdoor conditions (fluctuating sunlight with UV radiation), growth rates of calcified cells were almost 3.5 times higher compared to naked cells. Furthermore, relative electron transport rate was 114 % higher and non-photochemical quenching (NPQ) 281 % higher in the calcifying compared to the non-calcifying strain, implying higher energy transfer associated with higher NPQ in the presence of calcification. When exposed to natural solar radiation including UV radiation, maximal quantum yield of photosystem II was only slightly reduced in the calcifying but strongly reduced in the non-calcifying strain. Our results reveal an important role of coccoliths in mitigating light and UV stress in E. huxleyi.

Light Absorption and Partitioning in Response to Nitrogen in Apple Leaves

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 541a-541
Author(s):  
Lailiang Cheng ◽  
Leslie H. Fuchigami ◽  
Patrick J. Breen
Keyword(s):  
High Light ◽  
Thermal Dissipation ◽  
Photochemical Quenching ◽  
Light Conditions ◽  
Psii Efficiency ◽  
Fluorescence Measurements ◽  
Free Radical Formation ◽  
Highly Correlated ◽  
Non Photochemical Quenching ◽  
Leaf N

Bench-grafted Fuji/M26 apple trees were fertigated with different concentrations of nitrogen by using a modified Hoagland solution for 6 weeks, resulting in a range of leaf N from 1.0 to 4.3 g·m–2. Over this range, leaf absorptance increased curvilinearly from 75% to 92.5%. Under high light conditions (1500 (mol·m–2·s–1), the amount of absorbed light in excess of that required to saturate CO2 assimilation decreased with increasing leaf N. Chlorophyll fluorescence measurements revealed that the maximum photosystem II (PSII) efficiency of dark-adapted leaves was relatively constant over the leaf N range except for a slight drop at the lower end. As leaf N increased, non-photochemical quenching under high light declined and there was a corresponding increase in the efficiency with which the absorbed photons were delivered to open PSII centers. Photochemical quenching coefficient decreased significantly at the lower end of the leaf N range. Actual PSII efficiency increased curvilinearly with increasing leaf N, and was highly correlated with light-saturated CO2 assimilation. The fraction of absorbed light potentially used for free radical formation was estimated to be about 10% regardless of the leaf N status. It was concluded that increased thermal dissipation protected leaves from photo-oxidation as leaf N declined.

Sign in / Sign up

Export Citation Format

Share Document