scholarly journals Effects of the red:far-red light ratio on photosynthetic characteristics of greenhouse cut Chrysanthemum – Short communication

2013 ◽  
Vol 40 (No. 1) ◽  
pp. 40-43 ◽  
Author(s):  
Z.Q. Yang ◽  
Y.X Li ◽  
J.B. Zhang ◽  
J. Zhang ◽  
J. Zhu ◽  
...  
Keyword(s):  
Photosynthetic Rate ◽  
Red Light ◽  
Photochemical Efficiency ◽  
Photosynthetic Characteristics ◽  
Photochemical Quenching ◽  
Light Sources ◽  
Chlorophyll Fluorescence Parameters ◽  
Spad Value ◽  
Red Led ◽  
R:Fr Ratio

For the use of LED as a light source to regulate the photosynthesis of chrysanthemum leaves under greenhouse conditions, the effects of different red (660 &plusmn; 30 nm) to far-red (730 &plusmn; 30 nm) radiation ratios (R:FR) on the photosynthetic characteristics and chlorophyll fluorescence parameters of chrysanthemum leaves were studied. Red and far-red LED light sources were combined in different proportions to produce four R:FR ratio treatments: 0.5, 2.5, 4.5 and 6.5. The chlorophyll a content, SPAD value, net photosynthetic rate, light-saturated maximum photosynthetic rate, CO<sub>2</sub>-saturated carboxylation rate, apparent quantum efficiency and carboxylation efficiency were all the highest under the R:FR ratio of 2.5, followed by the R:FR ratio of 4.5. Potential photochemical efficiency of photosystem II, photochemical quenching and electron transport rate for the R:FR ratios of 2.5 and 4.5 were markedly higher than those for 0.5 and 6.5, however, those parameters did not differ significantly between the R:FR ratios of 2.5 and 4.5.

scholarly journals Photosynthesis, Chlorophyll Fluorescence, and Yield of Peanut in Response to Biochar Application

2021 ◽  
Vol 12 ◽  
Author(s):  
Shujun Wang ◽  
Junlin Zheng ◽  
Yujia Wang ◽  
Qingfeng Yang ◽  
Taotao Chen ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Leaf Gas Exchange ◽  
Photochemical Efficiency ◽  
Photochemical Quenching ◽  
Nitrogen Accumulation ◽  
Leaf Nitrogen Content ◽  
Chlorophyll Fluorescence Parameters ◽  
Plant Nitrogen

The effect of biochar application on photosynthetic traits and yield in peanut (Arachis hypogaea L.) is not well understood. A 2-year field experiment was conducted in Northwest Liaoning, China to evaluate the effect of biochar application [0, 10, 20, and 40 t ha−1 (B0, B10, B20, and B40)] on leaf gas exchange parameters, chlorophyll fluorescence parameters, and yield of peanut. B10 improved photochemical quenching at flowering and pod set and reduced non-photochemical quenching at pod set, relative to B0. B10 and B20 increased actual photochemical efficiency and decreased regulated energy dissipated at pod set, relative to B0. B10 significantly increased net photosynthetic rate, transpiration rate, stomatal conductance, and water use efficiency at flowering and pod set, relative to B0. Compared with B0, B10 significantly improved peanut yield (14.6 and 13.7%) and kernel yield (20.2 and 14.4%). Biochar application increased leaf nitrogen content. B10 and B20 significantly increased plant nitrogen accumulation, as compared to B0. The net photosynthetic rate of peanut leaves had a linear correlation with plant nitrogen accumulation and peanut yield. The application of 10 t ha−1 biochar produced the highest peanut yield by enhancing leaf photosynthetic capacity, and is thus a promising strategy for peanut production in Northwest Liaoning, China.

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. *********

Promoting pepper (Capsicum annuum) photosynthesis via chloroplast ultrastructure and enzyme activities by optimising the ammonium to nitrate ratio

2020 ◽  
Vol 47 (4) ◽  
pp. 303
Author(s):  
Jing Zhang ◽  
Jianming Xie ◽  
Yantai Gan ◽  
Jeffrey A. Coulter ◽  
Mohammed Mujitaba Dawuda ◽  
...  
Keyword(s):  
Plant Growth ◽  
Capsicum Annuum ◽  
Photosynthetic Rate ◽  
Large Subunit ◽  
Photochemical Efficiency ◽  
Chloroplast Ultrastructure ◽  
Photochemical Quenching ◽  
Gas Exchange Parameters ◽  
Chilli Pepper ◽  
N Assimilation

Optimal plant growth in many species is achieved when the two major forms of N are supplied at a particular ratio. In this pot experiment, the effects of five different ammonium:nitrate ratios (ANRs) (0:100, 12.5:87.5, 25:75, 37.5:62.5, and 50:50) on photosynthesis efficiency in chilli pepper (Capsicum annuum L.) plants were evaluated. The results showed that an ANR of 25:75 increased the contents of chl a, leaf area and dry matter, whereas chl b content was not affected by the ANRs. Regarding chlorophyll fluorescence, an ANR of 25:75 also enhanced the actual photochemical efficiency, photochemical quenching and maximum photosynthetic rate. However, the 0:100 and 50:50 ANRs resulted in higher values for nonphotochemical quenching. An inhibition of maximal photochemical efficiency was found when 50% NH4+ was supplied at the later stage of plant growth. The addition of 25% or 37.5% NH4+ was beneficial for gas exchange parameters and the 25% NH4+ optimised the thylakoid of chloroplasts. Compared with nitrate alone, 12.5–50% NH4+ upregulated glutamate dehydrogenase (GDH), the large subunit and the small subunit of Rubisco. It can be concluded that the 25:75 ANR accelerated N assimilation through active GDH, which provides a material basis for chloroplast and Rubisco formation, resulting in the increased photosynthetic rate and enhanced growth in chilli pepper.

scholarly journals Salinity reduced growth PS2 photochemistry and chlorophyll content in radish

2007 ◽  
Vol 64 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Muhammad Jamil ◽  
Shafiq ur Rehman ◽  
Kui Jae Lee ◽  
Jeong Man Kim ◽  
Hyun-Soon Kim ◽  
...  
Keyword(s):  
Leaf Area ◽  
Chlorophyll Content ◽  
Salt Concentration ◽  
Germination Rate ◽  
Photochemical Efficiency ◽  
Germination Percentage ◽  
Photochemical Quenching ◽  
Leaf Water Content ◽  
Spad Value ◽  
Salt Level

When plants are grown under saline conditions, photosynthetic activity decreases leading to reduced plant growth, leaf area, chlorophyll content and chlorophyll fluorescence. Seeds and seedlings of radish (Raphanus sativus L.) were grown in NaCl solutions under controlled greenhouse conditions. The NaCl concentrations in complete nutrient solutions were 0 (control), 4.7, 9.4 and 14.1 dS m-1. The salinity reduced germination percentage and also delayed the germination rate as the salt level increased. Lengths and fresh weights of root and shoot decreased with the increasing salt concentration. Furthermore, photochemical efficiency of PS2 (Fv/Fm), photochemical quenching coefficient (qP), non photochemical quenching coefficient (qN), leaf area and chlorophyll content (SPAD value) were also reduced (P < 0.001) by salt stress. In contrast, the Fo/Fm ratio increased with increasing salt concentration while salinity showed no effect on the efficiency of excitation captured by open PS2 (Fv'/Fm'), electron transport rate (ETR), and leaf water content. Linear regression shows that the photochemical efficiency of PS2 (Fv/Fm) had a positive relationship with the photochemical quenching coefficient (qP), leaf area and chlorophyll content but had no relation with Fv'/Fm', Fo/Fm, and qN.

PHOTOTHERAPY FOR MILD TO MODERATE ACNE VULGARIS WITH PORTABLE BLUE AND RED LED

2011 ◽  
Vol 04 (01) ◽  
pp. 45-52 ◽  
Author(s):  
GUANGDA LIU ◽  
CHANGE PAN ◽  
KAI LI ◽  
YUAN TAN ◽  
XUNBIN WEI
Keyword(s):  
Side Effects ◽  
Light Emitting Diode ◽  
Acne Vulgaris ◽  
Red Light ◽  
Light Sources ◽  
Light Emitting ◽  
Led Light ◽  
Led Phototherapy ◽  
Red Led ◽  
Complete Treatment

In this paper, we studied portable blue and red light-emitting-diode (LED) light sources in phototherapy for mild to moderate acne vulgaris to evaluate the efficacy and tolerance of patients. Patients, randomly divided into blue and red groups, received either blue or red LED phototherapy twice a week for four weeks. After complete treatment, the number of lesions reduced by 71.4% in the blue group, in contrast to 19.5% in the red group. No obvious side effects were observed during and one month after the treatment, except for some mild dryness mentioned by several patients.

scholarly journals Effects of Smoke-water on Photosynthetic Characteristics of Isatis indigotica Seedlings

2012 ◽  
Vol 2 (2) ◽  
pp. 24 ◽  
Author(s):  
Jie Zhou ◽  
Lei Fang ◽  
Xiao Wang ◽  
Lanping Guo ◽  
Luqi Huang
Keyword(s):  
Water Treatment ◽  
Stomatal Conductance ◽  
Plant Growth ◽  
Photochemical Efficiency ◽  
Photosynthetic Characteristics ◽  
Photochemical Quenching ◽  
Isatis Indigotica ◽  
Photochemical Efficiency Of Psii ◽  
Non Photochemical Quenching ◽  
Smoke Water

<p>Smoke-water (SW) had been reported to improve the growth of <em>Isatis indigotica</em>, a Chinese medicinal plant. However, there were very few reports on the mechanism of smoke-water improving plant growth. In this study the effects of smoke-water on the photosynthetic characteristics of <em>I.</em><em> indigotica</em> seedlings were investigated for the purpose of understanding the mechanism behind this improved plant growth. The results showed that net photosynthetic rate (<em>P<sub>n</sub></em>) was increased by smoke-water, reaching a maximum on 15, 5 and 15 d after treatment with smoke-water at dilutions of 1:500, 1:1000 and 1:2000 respectively. Transpiration rate (<em>T<sub>r</sub></em>) and stomatal conductance (<em>G<sub>s</sub></em>) both showed similar trends to<sub> </sub><em>P<sub>n</sub></em>, however, intercellular CO<sub>2</sub> concentration<em> </em>(<em>C<sub>i</sub></em>) was decreased with smoke-water treatment. The F<sub>v</sub>/F<sub>m</sub> was not significantly influenced by smoke-water treatment. The ?PSII was markedly promoted with the application of smoke-water (1:1000) compared with the control and the coefficient of photochemical quenching (qP) showed a similar trend to ?PSII. However the coefficient of non-photochemical quenching of chlorophyll (NPQ) was decreased with treatment of smoke-water. These findings indicate that smoke-water treatment induce an increase in photosynthesis and suggest the main factors leading to this might be the improved stomatal conductance and the enhanced level of the photochemical efficiency of PSII in leaves.</p>

Corrigendum to: Promoting pepper (Capsicum annuum) photosynthesis via chloroplast ultrastructure and enzyme activities by optimising the ammonium to nitrate ratio

2020 ◽  
Vol 47 (5) ◽  
pp. 473
Author(s):  
Jing Zhang ◽  
Jianming Xie ◽  
Yantai Gan ◽  
Jeffrey A. Coulter ◽  
Mohammed Mujitaba Dawuda ◽  
...  
Keyword(s):  
Plant Growth ◽  
Capsicum Annuum ◽  
Photosynthetic Rate ◽  
Large Subunit ◽  
Photochemical Efficiency ◽  
Chloroplast Ultrastructure ◽  
Photochemical Quenching ◽  
Gas Exchange Parameters ◽  
Chilli Pepper ◽  
N Assimilation

Optimal plant growth in many species is achieved when the two major forms of N are supplied at a particular ratio. In this pot experiment, the effects of five different ammonium:nitrate ratios (ANRs) (0:100, 12.5:87.5, 25:75, 37.5:62.5, and 50:50) on photosynthesis efficiency in chilli pepper (Capsicum annuum L.) plants were evaluated. The results showed that an ANR of 25:75 increased the contents of chl a, leaf area and dry matter, whereas chl b content was not affected by the ANRs. Regarding chlorophyll fluorescence, an ANR of 25:75 also enhanced the actual photochemical efficiency, photochemical quenching and maximum photosynthetic rate. However, the 0:100 and 50:50 ANRs resulted in higher values for nonphotochemical quenching. An inhibition of maximal photochemical efficiency was found when 50% NH4+ was supplied at the later stage of plant growth. The addition of 25% or 37.5% NH4+ was beneficial for gas exchange parameters and the 25% NH4+ optimised the thylakoid of chloroplasts. Compared with nitrate alone, 12.5–50% NH4+ upregulated glutamate dehydrogenase (GDH), the large subunit and the small subunit of Rubisco. It can be concluded that the 25:75 ANR accelerated N assimilation through active GDH, which provides a material basis for chloroplast and Rubisco formation, resulting in the increased photosynthetic rate and enhanced growth in chilli pepper.

scholarly journals Waterlogging tolerance and recovery capability screening in peanut: a comparative analysis of waterlogging effects on physiological traits and yield

PeerJ ◽  
2022 ◽  
Vol 10 ◽  
pp. e12741
Author(s):  
Ruier Zeng ◽  
Jing Cao ◽  
Xi Li ◽  
Xinyue Wang ◽  
Ying Wang ◽  
...  
Keyword(s):  
Photochemical Efficiency ◽  
Significant Negative Correlation ◽  
Photochemical Quenching ◽  
Waterlogging Tolerance ◽  
Sod Activity ◽  
Ps Ii ◽  
Spad Value ◽  
Mda Content ◽  
Non Photochemical Quenching ◽  
Maximum Photochemical Efficiency

Fifteen peanut varieties at the pod filling stage were exposed to waterlogging stress for 7 days, the enzyme activities and fluorescence parameters were measured after 7 days of waterlogging and drainage. The waterlogging tolerance and recovery capability of varieties were identified. After waterlogging, waterlogging tolerance coefficient (WTC) of relative electrolyte linkage (REL), malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and catalase (CAT) activity, non-photochemical quenching (NPQ) and photochemical quenching (qL) of leaves of most peanut varieties were increased, while the WTC of the soil and plant analysis development (SPAD) value, PS II actual quantum yield (ΦPS II), maximum photochemical efficiency (Fv/Fm) were decreased. After drainage, the WTC of REL, MDA content, SOD and CAT activity of leaves were decreased compared with that of after waterlogging, but these indicators of a few cultivars were increased. ΦPS II, Fv/Fm and qL can be used as important indexes to identify waterlogging recovery capability. There was a significant negative correlation between recovery capability and the proportion of reduction in yield, while no significant correlation was found between waterlogging tolerance and the proportion of reduction in yield. Therefore, it is recommended to select varieties with high recovery capability and less pod number reduction under waterlogging in peanut breeding and cultivation.

scholarly journals Effects of Cold Stress on the Photosynthesis and Antioxidant System of Rhododendron chrysanthum Pall.

2017 ◽  
Author(s):  
Xiaofu Zhou ◽  
Silin Chen ◽  
Hui Wu ◽  
Hongwei Xu
Keyword(s):  
Cold Stress ◽  
Antioxidant System ◽  
Molecular Mechanisms ◽  
Cold Resistance ◽  
Large Subunit ◽  
Photochemical Efficiency ◽  
Resistance Mechanisms ◽  
Photochemical Quenching ◽  
Control Group ◽  
Chlorophyll Fluorescence Parameters

Rhododendron chrysanthum Pall., live in Changbai Mountain being exposed to chilling temperature, high light intensities and water scarcity condition. To adapt to the harsh environment, the cold resistance mechanisms of R. chrysanthum have been successfully evolved in the long-term adaptive process. In our present work, the methods of proteomics combined with physiological and biochemical analyses were used to investigate the effects of cold stress on the photosynthesis and antioxidant system of Rhododendron chrysanthum Pall. and the molecular mechanisms involved in cold resistance of plants. A total of 153 photosynthesis related proteins were identified in present work, of which 7 proteins including Rubisco large subunit (rbcL) were up-regulated in experiment group (EG) compared with control group (CG). Simultaneously, four chlorophyll fluorescence parameters were measured in present study. The results showed that the maximum photochemical efficiency of photosystem II (Fv/Fm), actual quantum yield of PSII (Y(II)) and photochemical quenching (qP) were significantly higher in EG, whereas the non-photochemical quenching (NPQ) was notably decreased. Cold stress could lead to a significant reduction in electron transport rate (ETR) accompanied with an increase in excitation pressure (1-qP). The abundance of PetE which involved in the plants photosynthetic electron transfer was also significantly influenced by cold stress. Moreover, the up-regulated expressions and higher levels of enzymatic activities of Glutathione peroxidase (GPX) and Ascorbate peroxidases (APXs) were detected in EG. All these changes which can help plants to survive in low temperature are considered as the crucial parts of cold tolerance mechanisms. These results revealed that photosynthesis and redox adjustment play significant roles in the defense of cold-induced damage.

scholarly journals Evaluation of Photosynthetic Characters and Regulation Pattern of Photosynthesis Associated Gene in Two Mulberry Varieties

2021 ◽  
Vol 25 (04) ◽  
pp. 863-872
Author(s):  
Yong Li
Keyword(s):  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Metabolic Pathways ◽  
Carbon Fixation ◽  
Expression Patterns ◽  
Photochemical Efficiency ◽  
High Yield ◽  
Photochemical Quenching ◽  
Chlorophyll Metabolism ◽  
Photosynthetic Organisms

Photosynthetic characteristics and expression patterns of the photosynthesis-related genes in the high-yield mulberry variety E’Sang 1 (E1) and normal mulberry variety Husang 32 (H32) were investigated in this study. The observation of daily variation of photosynthesis in E1 and H32 indicated that the peak of net photosynthetic rate(Pn)inE1 variety was significantly higher than that inH32 (P <0.05). Meanwhile, the Pn-PAR and Pn-Ci responses of E1 and H32 were evaluated, and the results showed that the carboxylation efficiency and compensation saturation point were much higher in E1 rather thanH32. Importantly, the photosystem II actual photochemical efficiency and photochemical quenching coefficient in the leaves of E1 were significantly higher than those in H32 (P<0.05). Also, the activity of RuBP in E1 was higher than that in H32 (P >0.05). Based on the RNA-seq data, a total of 3,356 differentially expressed genes (DEGs) were detected among different time points between E1 and H32. Of these, 1,136 DEGs were involved in the metabolic pathways, including three main photosynthesis-related metabolic pathways (i.e., carbon fixation in photosynthetic organisms, carbon metabolism, and porphyrin and chlorophyll metabolism). Meanwhile, 10 novel DEGs related to photosynthesis were detected, and four potential key genes of them could account for the differences in net photosynthetic rate and yield betweenH32 and E1.This study could provide important insights into the molecular breeding of mulberry varieties with high photosynthetic efficiency and contribute to understanding the genetic mechanism of photosynthesis.© 2021 Friends Science Publishers

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