Effects of shading on leaf physiology and morphology in the ‘Yinhong’ grape plants

Abstract Shading is a practical measure to reduce the heat stress to grape trees in the summer. However, inappropriate shading will cause the reduction in leaf photosynthesis and consequently the retardation of growth for the plants or the loss of fruit yield and quality for the mature grape trees. In this study we have used 1-year-old ‘YinHong’ grape plants growing under different levels of shading, ranging from full sunlight 0% to 80% reduction, to investigate their growth, physiological and biochemical responses. The results show that shading rate =45% did not significantly affect grape growth. Shading over 45% reduction of the full sunlight, the growth of the grape plants were started to be inhibited. In addition, soluble protein content, the activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), PSII photochemical efficiency (Fv/Fm), PSII potential activity1(Fv/Fo) and photochemical quenching (qP) were decreased, whereas free proline, malondialdehyde (MDA) content, the non-photochemical quenching coefficient (qN) and the ratio of the palisade/spongy tissue were gradually increased. In particular, significant changes in plant growth, photosynthetic and the other physiological and biochemical characteristics were observed under a strong shading.

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

PeerJ ◽

10.7717/peerj.12741 ◽

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.

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Determining Freezing Injury from Changes in Chlorophyll Fluorescence in Potted Oleander Plants

HortScience ◽

10.21273/hortsci.46.6.895 ◽

2011 ◽

Vol 46 (6) ◽

pp. 895-900 ◽

Cited By ~ 4

Author(s):

Julián Miralles-Crespo ◽

Juan Antonio Martínez-López ◽

José Antonio Franco-Leemhuis ◽

Sebastián Bañón-Arias

Keyword(s):

Chlorophyll Fluorescence ◽

Chilling Stress ◽

Photochemical Efficiency ◽

Freezing Injury ◽

Photochemical Quenching ◽

Biochemical Indicators ◽

Freezing Temperatures ◽

Non Photochemical Quenching ◽

Maximum Photochemical Efficiency ◽

Physiological And Biochemical

Physiological and biochemical indicators that reflect the responses of plants to chilling stress could be useful for identifying plant damage caused by freezing or other stresses. The objective of this study was to determine any relationship between changes in chlorophyll fluorescence and the appearance of visual symptoms resulting from freezing temperatures in two cultivars of oleander. In the least frost-sensitive cultivar (yellow oleander), freezing temperatures (–4 °C for 3 h) did not produce changes in the photochemical parameters. In the more frost-sensitive cultivar (pink oleander), non-photochemical quenching (NPQ) and the maximum photochemical efficiency of photosystem II (Fv/Fm) decreased after the same freezing treatment. The first of these potential indicators remained low, whereas the second steadily recovered during the 4 months after freezing simulation. The results suggest that measuring chlorophyll fluorescence may provide a rapid method for assessing freezing injury in oleander.

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

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha47311437 ◽

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. *********

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Differential responses between mature and young leaves of sunflower plants to oxidative stress caused by water deficit

Ciência Rural ◽

10.1590/s0103-84782010000600008 ◽

2010 ◽

Vol 40 (6) ◽

pp. 1290-1294 ◽

Cited By ~ 11

Author(s):

Inês Cechin ◽

Natália Corniani ◽

Terezinha de Fátima Fumis ◽

Ana Catarina Cataneo

Keyword(s):

Water Stress ◽

Gas Exchange ◽

Leaf Gas Exchange ◽

Intercellular Co2 Concentration ◽

Leaf Age ◽

Co2 Concentration ◽

Mature Leaves ◽

Young Leaves ◽

Mda Content ◽

Gas Exchange Characteristics

The effects of water stress and rehydration on leaf gas exchange characteristics along with changes in lipid peroxidation and pirogalol peroxidase (PG-POD) were studied in mature and in young leaves of sunflower (Helianthus annuus L.), which were grown in a greenhouse. Water stress reduced photosynthesis (Pn), stomatal conductance (g s), and transpiration (E) in both young and mature leaves. However, the amplitude of the reduction was dependent on leaf age. The intercellular CO2 concentration (Ci) was increased in mature leaves but it was not altered in young leaves. Instantaneous water use efficiency (WUE) in mature stressed leaves was reduced when compared to control leaves while in young stressed leaves it was maintained to the same level as the control. After 24h of rehydration, most of the parameters related to gas exchange recovered to the same level as the unstressed plants except gs and E in mature leaves. Water stress did not activated PG-POD independently of leaf age. However, after rehydration the enzyme activity was increased in mature leaves and remained to the same as the control in young leaves. Malondialdehyde (MDA) content was increased by water stress in both mature and young leaves. The results suggest that young leaves are more susceptible to water stress in terms of gas exchange characteristics than mature leaves although both went through oxidative estresse.

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Low induction of non-photochemical quenching and high photochemical efficiency in the annual desert plantAnastatica hierochuntica

Physiologia Plantarum ◽

10.1111/ppl.12146 ◽

2014 ◽

Vol 151 (4) ◽

pp. 544-558 ◽

Cited By ~ 8

Author(s):

Amir Eppel ◽

Ruth Shaked ◽

Gil Eshel ◽

Simon Barak ◽

Shimon Rachmilevitch

Keyword(s):

Photochemical Efficiency ◽

Photochemical Quenching ◽

Non Photochemical Quenching

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Effects of lead on growth, osmotic adjustment, antioxidant activity and photosynthetic responses in Phoebe chekiangensis seedlings

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha48311933 ◽

2020 ◽

Vol 48 (3) ◽

pp. 1637-1648

Author(s):

Yujie YANG ◽

Wenjie LI ◽

Xinru HE ◽

Die HU ◽

Yongjun FEI

Keyword(s):

Intercellular Co2 Concentration ◽

Co2 Concentration ◽

Root Surface ◽

Root Surface Area ◽

Photosynthetic Parameters ◽

Root Volume ◽

Root Shoot Ratio ◽

Mda Content ◽

Photosynthetic Responses ◽

Intercellular Co2

Experiments were conducted on 1-year Phoebe chekiangensis seedlings treated by different concentration (0, 300, 600, 900, 1200 mg/L) of Pb (NO3)2. Sixty days later, determination was implemented on seedling growth, physiological and photosynthetic parameters. The results showed that the lower concentration treated could promote the growth of the seedlings. But with the increase of concentration of lead, P. chekiangensis seedling height increment, ground diameter growth, whole biomass, total root surface area, root volume, total root length and root activity decreased, while root-shoot ratio present a rising trend. With the increase of concentration of Pb(NO3)2 solution, the membrane permeability and MDA content of P. chekiangensis seedlings showed a trend of rise after the first reduce; the protein content and chlorophyll content presented a trend of decrease after the first increase; while the POD, SOD and CAT activity increased firstly but decreased afterwards; the net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate were all increase at first then decrease, which indicated that protection enzyme activity and membrane was damaged thus the growth of P. chekiangensis seedlings was inhibited.

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Antioxidant Protection of Photosynthesis in Two Cashew Progenies Under Salt Stress

Journal of Agricultural Science ◽

10.5539/jas.v10n10p388 ◽

2018 ◽

Vol 10 (10) ◽

pp. 388

Author(s):

Anselmo F. da Silva ◽

Valéria F. de O. Sousa ◽

Gisele L. dos Santos ◽

Eugênio S. Araújo Júnior ◽

Sérgio L. F. da Silva ◽

...

Keyword(s):

Salt Stress ◽

Quantum Efficiency ◽

Salinity Stress ◽

Intercellular Co2 Concentration ◽

Co2 Concentration ◽

Co2 Assimilation ◽

Photochemical Activity ◽

Photochemical Quenching ◽

Tree Seedlings ◽

Cashew Tree

The present work evaluated the indicators of photosynthetic efficiency and antioxidative protection in cashew tree seedlings subjected to salinity stress. The study was conducted with seedlings of two advanced dwarf cashew clones (CCP09 and CCP76) subjected to salt stress with increasing doses of NaCl (0, control; 25; 50; 75; 100 mM) in the nutrient solution for 30 days under greenhouse conditions. The variables of gas exchange, CO2 assimilation (PN), stomatal conductance (gS), transpiration (E), intercellular CO2 concentration (CI), photochemical activity, potential quantum efficiency (Fv/Fm), effective quantum efficiency (ΔF/Fm’) of photosystem II (PSII), photochemical quenching (qP), non-photochemical quenching (NPQ) electron transport rate (ETR) as well as the indicators of damage and oxidative protection were measured. Under these conditions, there was an intense accumulation Na+ associated with a reduction in the K+/Na+ ratio in the leaves of both clones in response to salt, with higher values for this ratio in clone CCP09 than in CCP76 the highest concentration of NaCl (100 mM). Salinity reduced PN, gS and E in the two clones evaluated, with lower reductions in CCP09 than in CCP76 at the highest salt dose. Instantaneous carboxylation (PN/CI) and water use (PN/E) efficiencies were strongly restricted by salinity but were less affected in CCP09 than in CCP76. Salinity stress also increased hydrogen peroxide (H2O2) levels in CCP09, whereas lipid peroxidation decreased in both progenies. The clones presented specific antioxidant responses due to greater enzymatic and non-enzymatic activity in CCP76, in addition to the activity of phenol peroxidase (POX) in CCP09.

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Characteristics of Mango Leaf Photosynthetic Inhibition by Enhanced UV-B Radiation

Horticulturae ◽

10.3390/horticulturae7120557 ◽

2021 ◽

Vol 7 (12) ◽

pp. 557

Author(s):

Hong Wang ◽

Yujian Guo ◽

Jianjun Zhu ◽

Kun Yue ◽

Kaibing Zhou

Keyword(s):

Chlorophyll A ◽

Mangifera Indica ◽

Soluble Sugar ◽

Intercellular Co2 Concentration ◽

Carbon Assimilation ◽

Co2 Concentration ◽

Photochemical Reactions ◽

Photochemical Quenching ◽

Hill Reaction ◽

Photosynthetic Inhibition

To investigate the photosynthetic change characteristics of mango leaves under enhanced UV-B radiation, adult ‘Tainong No. 1′ mango (Mangifera indica) trees were treated (N = nine individuals) with simulated enhanced UV-B radiation [24 and 96 kJ/(m2·d)] in the field, and the photochemical reactions, activities of key enzymes in carbon assimilation, and the expression of genes were observed. The results showed that compared with the control, there was a decrease in tree yield, soluble sugar, sugar–acid ratio, and vitamin C of the fruits under the 96 kJ/(m2·d) treatment, while no significant changes were observed under 24 kJ/(m2·d). After 20 or 40 days, the leaves’ net photosynthetic rate (Pn), stomatal conductance (Sc), transpiration rate (Tr), intercellular CO2 concentration (Ci), and chlorophyll a/b under exposure to 96 kJ/(m2·d) of UV-B were significantly lower than in the control, whereas chlorophyll a, chlorophyll b, carotenoids, Hill reaction activity, photochemical quenching coefficient (qP), and Rubisco activities were significantly higher. In contrast, the Hill activity and Rubisco activity under 24 kJ/(m2·d) were significantly higher than the control, and increased by 350% and 30.8%, respectively, while Pn, Sc, Tr, Ci, and the content of photosynthetic pigments were similar to the control. The expression of gene coding the Rubisco big subunit (rbcL) was inhibited by the 96 kJ/(m2·d) treatment. We conclude that stomatal limitation was directly induced by 96 kJ/(m2·d), resulting in the inhibition of photosynthesis and the reduction in yield and deterioration of the quality of mango.

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Acclimatization of photosynthetic apparatus and antioxidant metabolism to excess soil cadmium in Buddleja spp.

Scientific Reports ◽

10.1038/s41598-020-78593-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Weichang Gong ◽

Bruce L. Dunn ◽

Yaqing Chen ◽

Yunmei Shen

Keyword(s):

Quantum Yield ◽

Photosynthetic Apparatus ◽

Photochemical Quenching ◽

Effective Quantum Yield ◽

Antioxidant Metabolism ◽

Cellular Reactive Oxygen Species ◽

Soil Cadmium ◽

Non Photochemical Quenching ◽

Cd Translocation ◽

Physiological And Biochemical

AbstractHeavy metal (HM) pollutants can cause serious phytotoxicity or oxidative stress in plants. Buddleja L., commonly known as “butterfly bushes”, are frequently found growing on HM-contaminated land. However, to date, few studies have focused on the physiological and biochemical responses of Buddleja species to HM stress. In this study, potted seedlings of B. asiatica Lour. and B. macrostachya Wall. ex Benth. were subjected to various cadmium (Cd) concentrations (0, 25, 50, 100, and 200 mg kg−1) for 90 days. Both studied Buddleja species showed restricted Cd translocation capacity. Exposure to Cd, non-significant differences (p > 0.05) were observed, including quantum yield of photosystem II (PSII), effective quantum yield of PSII, photochemical quenching and non-photochemical quenching in both species between all studied Cd concentrations. Moreover, levels of cellular reactive oxygen species (ROS) significantly declined (p < 0.05) with low malondialdehyde concentrations. In B. asiatica, high superoxide dismutase and significantly enhanced (p < 0.05) peroxidase (POD) activity contributed greatly to the detoxification of excess ROS, while markedly enhanced POD activity was observed in B. macrostachya. Additionally, B. macrostachya showed higher membership function values than did B. asiatica. These results suggested that both Buddleja species exhibited high Cd resistance and acclimatization.

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High night temperature decreases leaf photosynthesis and pollen function in grain sorghum

Functional Plant Biology ◽

10.1071/fp11035 ◽

2011 ◽

Vol 38 (12) ◽

pp. 993 ◽

Cited By ~ 70

Author(s):

P. V. Vara Prasad ◽

Maduraimuthu Djanaguiraman

Keyword(s):

Climate Models ◽

Seed Set ◽

Membrane Damage ◽

Photochemical Efficiency ◽

Pollen Grains ◽

High Temperature Stress ◽

Photochemical Quenching ◽

Night Temperature ◽

Non Photochemical Quenching ◽

Quantum Yield Of Psii

High temperature stress is an important abiotic stress limiting sorghum (Sorghum bicolor (L.) Moench) yield in arid and semiarid regions. Climate models project greater increases in the magnitude of night temperature compared with day temperature. We hypothesise that high night temperature (HNT) during flowering will cause oxidative damage in leaves and pollen grains, leading to decreased photosynthesis and seed-set, respectively. The objectives of this research were to determine effects of HNT on (1) photochemical efficiency and photosynthesis of leaves, and (2) pollen functions and seed-set. Sorghum plants (hybrid DK-28E) were exposed to optimum night temperature (ONT; 32 : 22°C, day maximum : night minimum) or HNT (32 : 28°C, day maximum : night minimum) for 10 days after complete panicle emergence. Exposure to HNT increased thylakoid membrane damage and non-photochemical quenching. However, HNT decreased chlorophyll content, quantum yield of PSII, photochemical quenching, electron transport rate and photosynthesis of leaves as compared with ONT. Exposure to HNT increased the reactive oxygen species (ROS) level of leaves and pollen grains. Lipid molecular species analyses in pollen grains showed that HNT decreased phospholipid saturation levels and altered various phospholipid levels compared with ONT. These changes in phospholipids and greater ROS in pollen grains may be responsible for decreased pollen function, leading to lower seed-set.

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