Physiological and Transcriptomic Analysis of Tree Peony (Paeonia section Moutan DC.) in Response to Drought Stress

Tree peony (Paeonia section Moutan DC.) is a famous ornamental plant, and P. ostii has been used for seed oil production in China because it is rich in α-linolenic acid. P. ostii has some resistance to drought, but lack of water can severely hinder its growth and development in arid areas. In order to clarify drought stress induced physiological and molecular changes of P. ostia, its physiological and transcriptomic analyses were performed under drought stress, and we found that P. ostii leaves drooped significantly 12 days after treatment and observed a significant increase in all detected physiological indices in response to drought treatment except leaf water content, chlorophyll, and carotenoid content. Meanwhile, the activity of three antioxidant enzymes basically increased under drought treatment. Moreover, drought treatment significantly reduced photosynthetic and chlorophyll fluorescence parameters except non-photochemical quenching (qN), and maintained more intact mesophyll cell structures. Additionally, many differentially expressed genes (DEGs) were found by transcriptome sequencing, which play an important role in P. ostia drought tolerance by controlling a variety of biological processes, including the reactive oxygen species (ROS) system, chlorophyll degradation and photosynthetic competency, fatty acid metabolism, proline metabolism, biosynthesis of secondary metabolism, and plant hormone metabolism. These results provide a better understanding of P. ostii responses to drought stress.

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Comparative Proteomics of Root Apex and Root Elongation Zones Provides Insights into Molecular Mechanisms for Drought Stress and Recovery Adjustment in Switchgrass

Proteomes ◽

10.3390/proteomes8010003 ◽

2020 ◽

Vol 8 (1) ◽

pp. 3 ◽

Cited By ~ 2

Author(s):

Zhujia Ye ◽

Sasikiran Reddy Sangireddy ◽

Chih-Li Yu ◽

Dafeng Hui ◽

Kevin Howe ◽

...

Keyword(s):

Mass Spectrometry ◽

Drought Stress ◽

Molecular Mechanisms ◽

Root Zone ◽

Root Apex ◽

Root Tip ◽

Leaf Water Content ◽

Severe Drought ◽

Proteomics Data ◽

Drought Treatment

Switchgrass plants were grown in a Sandwich tube system to induce gradual drought stress by withholding watering. After 29 days, the leaf photosynthetic rate decreased significantly, compared to the control plants which were watered regularly. The drought-treated plants recovered to the same leaf water content after three days of re-watering. The root tip (1cm basal fragment, designated as RT1 hereafter) and the elongation/maturation zone (the next upper 1 cm tissue, designated as RT2 hereafter) tissues were collected at the 29th day of drought stress treatment, (named SDT for severe drought treated), after one (D1W) and three days (D3W) of re-watering. The tandem mass tags mass spectrometry-based quantitative proteomics analysis was performed to identify the proteomes, and drought-induced differentially accumulated proteins (DAPs). From RT1 tissues, 6156, 7687, and 7699 proteins were quantified, and 296, 535, and 384 DAPs were identified in the SDT, D1W, and D3W samples, respectively. From RT2 tissues, 7382, 7255, and 6883 proteins were quantified, and 393, 587, and 321 proteins DAPs were identified in the SDT, D1W, and D3W samples. Between RT1 and RT2 tissues, very few DAPs overlapped at SDT, but the number of such proteins increased during the recovery phase. A large number of hydrophilic proteins and stress-responsive proteins were induced during SDT and remained at a higher level during the recovery stages. A large number of DAPs in RT1 tissues maintained the same expression pattern throughout drought treatment and the recovery phases. The DAPs in RT1 tissues were classified in cell proliferation, mitotic cell division, and chromatin modification, and those in RT2 were placed in cell wall remodeling and cell expansion processes. This study provided information pertaining to root zone-specific proteome changes during drought and recover phases, which will allow us to select proteins (genes) as better defined targets for developing drought tolerant plants. The mass spectrometry proteomics data are available via ProteomeXchange with identifier PXD017441.

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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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Chlorophyll fluorescence response of wheat to exogenous application of growth regulators under terminal drought stress

Annales Universitatis Mariae Curie-Sklodowska sectio C – Biologia ◽

10.17951/c.2015.70.1.13 ◽

2015 ◽

Vol 70 (1) ◽

pp. 13

Author(s):

Hamid Mohammadi ◽

Mohsen Janmohammadi ◽

Naser Sabaghnia

Keyword(s):

Chlorophyll Fluorescence ◽

Drought Stress ◽

Electron Transport ◽

Quantum Yield ◽

Photochemical Quenching ◽

Chlorophyll Fluorescence Parameters ◽

Fluorescence Parameters ◽

Exogenous Application ◽

Terminal Drought ◽

Terminal Drought Stress

Drought stress negatively affects plant photosynthesis and disturbs the electron transport activity. Evaluation of the chlorophyll fluorescence parameters might reflect influence of the environmental stress on plants and can be applied as an indicator of the primary photochemistry of photosynthesis. In current study the effect of foliar application of benzylaminopurine (BAP, a synthetic cytokinin) and abscisic acid (ABA) on chlorophyll fluorescence parameters of relatively drought tolerant (Pishtaz) and susceptible (Karaj3) bread wheat genotypes under well watered and terminal water deficit condition have been evaluated. Terminal drought was induced by withholding water at anthesis stage (Zadoks scale 65). Results showed that coefficient of non-photochemical quenching of variable fluorescence (qN), quantum yield of PS II photochemistry (ΦPSII) and photochemical quenching (qP) were affected by hormone spray treatments. So that evaluation of parameters at 7 day after foliar treatments revealed that ABA significantly increased electron transport rate (ETR) and qN while considerably decreased ΦPSII, gs and maximum quantum yield of photosystem II (Fv/Fm). However exogenous application of cytokinin could increase gs, Fv/Fm and ΦPSII and the highest value of these parameters was recorded in cytokinin treated plants of Pishtaze cv. under well watered condition. Nevertheless, evaluation of the parameters in different periods after spraying showed that with approaching the maturity stage some traits like as gs, Fv/Fm and ETR significantly decreased in both genotypes. Evaluation of gs and Chlorophyll fluorescence parameters of genotypes between different irrigation levels showed that although cv. Pishtaz showed higher performance of PSII under well watered condition, it failed to maintain its superiority under stress condition. This finding suggests that some more responsive parameter like gs, Fv/Fm and ΦPSII can be considered as reliable indicator for understanding the biochemical and physiological effects of exogenous application of phytohormones under terminal drought stress.

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Effect of Drought Stress on Chlorophyll Fluorescence Parameters, Phytochemical Contents, and Antioxidant Activities in Lettuce Seedlings

Horticulturae ◽

10.3390/horticulturae7080238 ◽

2021 ◽

Vol 7 (8) ◽

pp. 238

Author(s):

Yu Kyeong Shin ◽

Shiva Ram Bhandari ◽

Jung Su Jo ◽

Jae Woo Song ◽

Jun Gu Lee

Keyword(s):

Ascorbic Acid ◽

Chlorophyll Fluorescence ◽

Drought Stress ◽

Quantum Yield ◽

Antioxidant Activities ◽

Growth Parameters ◽

Photochemical Quenching ◽

Total Phenol Content ◽

Effective Quantum Yield ◽

Chlorophyll Fluorescence Parameters

This study monitored changes in chlorophyll fluorescence (CF), growth parameters, soil moisture content, phytochemical content (proline, ascorbic acid, chlorophyll, total phenol content (TPC), and total flavonoid content (TFC)), and antioxidant activities in 12-day-old lettuce (Lactuca sativa L.) seedlings grown under drought stress (no irrigation) and control (well irrigated) treatments in controlled conditions for eight days. Measurements occurred at two-day intervals. Among ten CF parameters studied, effective quantum yield of photochemical energy conversion in PSII (Y(PSII)), coefficient of photochemical quenching (qP), and coefficient of photochemical quenching of variable fluorescence based on the lake model of PSII (qL) significantly decreased in drought-stressed seedlings from day 6 of treatment compared to control. In contrast, maximum quantum yield (Fv/Fm), ratio of fluorescence (Rfd), and quantum yield of non-regulated energy dissipation in PSII (Y(NO)) were significantly affected only at the end. All growth parameters decreased in drought-stressed seedlings compared to control. Proline started increasing from day 4 and showed ~660-fold elevation on day 8 compared to control. Chlorophyll, ascorbic acid, TPC, TFC, and antioxidant activities decreased in drought-stressed seedlings. Results showed major changes in all parameters in seedlings under prolonged drought stress. These findings clarify effects of drought stress in lettuce seedlings during progressive drought exposure and will be useful in the seedling industry.

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Comparative research of photosynthetic processes in selected poikilohydric organisms from Mediterranean and Central-European alpine habitats

Czech Polar Reports ◽

10.5817/cpr2018-2-24 ◽

2018 ◽

Vol 8 (2) ◽

pp. 286-298

Author(s):

Gabriella Nora Maria Giudici ◽

Josef Hájek ◽

Miloš Barták ◽

Svatava Kubešová

Keyword(s):

Czech Republic ◽

Chlorophyll Fluorescence ◽

Photochemical Quenching ◽

Marchantia Polymorpha ◽

Effective Quantum Yield ◽

Response Curves ◽

Chlorophyll Fluorescence Parameters ◽

Fluorescence Parameters ◽

Mediterranean Habitats ◽

Non Photochemical Quenching

Dehydration-induced decrease in photosynthetic activity was investigated in five poikilohydric autotrophs using chlorophyll fluorescence parameters recorded during controlled desiccation. For the study, two representatives of mosses from alpine zone (Rhizomnium punctatum, Rhytidiadelphus squarrosus) of the Jeseníky Mts. (Czech Republic) were used. Other two experimental species were mediterranean habitats liverwort (Pellia endiviifolia) and moss (Palustriella commutata), collected from under Woodwardia radicans canopy in the Nature Reserve Valle delle Ferriere (Italy). The last species was a liverwort (Marchantia polymorpha) collected from lowland site (Brno, Moravia, Czech Republic). We investigated the relationship between relative water content (RWC) and several chlorophyll fluorescence parameters evaluating primary photochemical processes of photosynthesis, such as effective quantum yield of photosynthetic processes in photosystem II (ΦPSII), and non-photochemical quenching (qN). With desiccation from fully wet (RWC = 100%) to dry state (RWC = 0%), ΦPSII exhibited a rapid (R. punctatum) and slow decline of ΦPSII (R. squarrosus, P. endiviifolia, M. polymorpha, and P. commutata). Shapes of dehydration-response curves were species-specific. RWC0.5, i.e. the RWC at which the sample showed half of maximum ΦPSII, reflected the species-specificity. It reached 65% in desiccation sensitive (R. punctatum), 53% and 43% in semi-tolerant (P. commutata and R. squarrosus), 24% and 18% in desiccation-tolerant species (P. endiviifolia and M. polymorpha). In all experimental species, non-photochemical quenching (qN) of absorbed light energy showed high values at RWC = 100% and a slight increase with desiccation. Steady state chlorophyll fluorescence (FS) remained high during desiccation and was not correlated with ΦPSII.

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The soil hydrogel improved photosynthetic performance of beech seedlings treated under drought

Plant Soil and Environment ◽

10.17221/170/2013-pse ◽

2013 ◽

Vol 59 (No. 10) ◽

pp. 446-451 ◽

Cited By ~ 5

Author(s):

G. Jamnická ◽

Ľ. Ditmarová ◽

D. Kurjak ◽

J. Kmeť ◽

E. Pšidová ◽

...

Keyword(s):

Quantum Efficiency ◽

Photosynthetic Performance ◽

Photochemical Quenching ◽

Severe Drought ◽

Drought Treatment ◽

Fast Kinetics ◽

Thermal Energy Dissipation ◽

Fagus Sylvatica L ◽

Common Substrate ◽

Non Photochemical Quenching

The effect of soil amendment with the STOCKOSORB®500 MICRO hydrophilic polymer on the photosynthetic traits in beech seedlings (Fagus sylvatica L.) during 50 days of dehydration was investigated. Dehydration was detected through osmotic potential (Ψs) in the assimilatory organs of beech seedlings. The addition of Stockosorb positively affected the CO2 assimilation rate (A) and instantaneous water use efficiency (A/T), for severely drought-treated seedlings. In comparison with irrigated plants, the values of A of non-irrigated plants with Stockosorb substrate decreased by 50%, and in non-irrigated plants with common substrate by 88%. The fast kinetics of chlorophyll a fluorescence indicated chronic photoinhibition under drought treatment without Stockosorb, while no significant changes in maximal quantum efficiency (Fv/Fm) were recorded under drought treatment with Stockosorb. The actual quantum efficiency of PSII (ΦPSII) markedly decreased in both treatments – with and without Stockosorb, though significant differences were found only between control treatments and drought treatment without Stockosorb. Moreover, the thermal energy dissipation (NPQ) was strongly limited under severe drought stress. The capacity to down regulate PSII functionality through non-photochemical quenching was maintained under drought treatment with Stockosorb. The results indicate that an amendment with soil conditioner significantly improved the photosynthetic performance of drought-stressed beech seedlings.

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Cold-induced photoinhibition and foliar pigment dynamics of Eucalyptus nitens seedlings during establishment

Functional Plant Biology ◽

10.1071/pp01039 ◽

2001 ◽

Vol 28 (11) ◽

pp. 1133 ◽

Cited By ~ 1

Author(s):

Dugald C. Close ◽

Chris L. Beadle ◽

Mark J. Hovenden

Keyword(s):

Chlorophyll Fluorescence ◽

Protein Complexes ◽

Photochemical Quenching ◽

Eucalyptus Nitens ◽

Light Conditions ◽

National Academy Of Sciences ◽

Experimental Site ◽

Chlorophyll Fluorescence Parameters ◽

Non Photochemical Quenching ◽

Academy Of Sciences

The effects of cold-induced photoinhibition on chlorophyll and carotenoid dynamics and xanthophyll cycling in Eucalyptus nitens (Deane and Maiden) Maiden were assessed between planting and 32 weeks after planting. The seedlings were fertilised or nutrient-deprived (non-fertilised) before planting and shaded or not shaded after planting. The experimental site was 700 m a.s.l., which is considered marginal for establishment of E. nitens plantations in Tasmania due to low mean annual minimum temperatures. Low temperature–high light conditions caused a reduction in variable to maximal chlorophyll fluorescence ratio (F v /F m ), which was more pronounced in non-fertilised than in fertilised seedlings. Shadecloth shelters alleviated this depression. Except in shaded fertilised seedlings, F v /F m did not recover to the level before planting until after 20 weeks. Total chlorophyll content was initially reduced in shaded treatments but subsequently increased with increasing temperatures and F v /F m. Total xanthophyll content and xanthophylls per unit chlorophyll remained relatively constant in fertilised seedlings but decreased in non-fertilised seedlings within 2 weeks after planting. Total xanthophyll and xanthophylls per unit chlorophyll subsequently recovered in non-shaded, non-fertilised seedlings with increasing temperatures and F v /F m. Diurnal [yield and non-photochemical quenching (NPQ) and seasonal (F v /F m) variation in chlorophyll fluorescence parameters were not reflected in xanthophyll cycling during the period of most severe photoinhibition. This result may indicate that chlorophyll–xanthophylls protein complexes form in winter-acclimated E. nitens foliage as have been demonstrated to occur in Eucalyptus pauciflora Sieb. ex Spreng. (Gilmore and Ball 2000, Proceedings of the National Academy of Sciences USA 97, 11098–11101).

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Photoinhibition of photosynthesis in Antarctic lichen Usnea antarctica. II. Analysis of non-photochemical quenching mechanisms activated by low to medium light doses

Czech Polar Reports ◽

10.5817/cpr2014-1-10 ◽

2014 ◽

Vol 4 (1) ◽

pp. 90-99 ◽

Cited By ~ 4

Author(s):

Petra Očenášová ◽

Miloš Barták ◽

Josef Hájek

Keyword(s):

High Light ◽

Photochemical Quenching ◽

Ps Ii ◽

Chlorophyll Fluorescence Parameters ◽

Main Emphasis ◽

James Ross Island ◽

Quenching Mechanisms ◽

Non Photochemical Quenching ◽

Short Time ◽

Energy Dependent

The paper focus sensitivity of an Antarctic lichen Usnea antarctica to photoinhibition studied under controlled laboratory conditions. Main emphasis was given to the analysis of quenching mechanisms, i.e. deexcitation pathways of absorbed light energy exploited in non-photochemical processes. Thalli of U. antarctica were collected at the James Ross Island, Antarctica (57°52´57´´ W, 63°48´02´´ S) and transferred in dry state to the Czech Republic. After rewetting in a laboratory, they were exposed to medium light intensities (300, 600 and 1000 mmol m-2 s-1 of photosynthetically active radiation) for 6 h. Before and during photoinhibitory treatments, chlorophyll fluorescence parameters, photoinhibitory (qI), state 1-2 transition (qT), and energy-dependent quenching (qE) in particular were measured to evaluate dose- and time-dependent changes in these parameters. The results showed that among the components forming non-photochemical quenching (qN), qI contributes to the largest extent to qN, while qE and qT contribute less. This finding differs from our earlier studies made in a short term-, and high light-treated U. antarctica that found qE together with qI is the most important part of non-photochemical quenching. Possible explanation is that photoinhibition in PS II in U. ant-arctica, when induced by low to medium light, activates qE to only limited extend and for a relatively short time (tens of minutes). With prolonged high light treatment lasting several hours, qE tends to be reduced to the values close to zero and qI then forms a major part of qN.

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Comparative Study of Drought Stress Effects on Traditional and Modern Apple Cultivars

Plants ◽

10.3390/plants10030561 ◽

2021 ◽

Vol 10 (3) ◽

pp. 561

Author(s):

Ines Mihaljević ◽

Marija Viljevac Vuletić ◽

Domagoj Šimić ◽

Vesna Tomaš ◽

Daniela Horvat ◽

...

Keyword(s):

Lipid Peroxidation ◽

Drought Stress ◽

Water Content ◽

Leaf Water ◽

Carotenoid Content ◽

Chlorophyll Fluorescence Induction ◽

Leaf Water Content ◽

Commercial Cultivar ◽

Golden Delicious ◽

Apple Cultivars

Genotype-dependent responses of apples to drought stress were evaluated between commercial and traditional apple cultivars. The results indicate different mechanisms of tolerance to investigated drought stress conditions. Chlorophyll fluorescence induction (OJIP) parameters, chlorophyll and carotenoid content, malondialdehyde (MDA), hydrogen peroxide (H2O2), proline, phenols and leaf water content (WC) were measured. The traditional cultivar “Crvenka” confirmed the best tolerance to a drought stress condition, presenting higher photosynthetic efficiency, higher leaf water content, higher levels of chlorophyll content and lower lipid peroxidation with greater membrane stability. The commercial cultivar “Golden Delicious Reinders” showed decreased water content in leaves, increased lipid peroxidation levels and photoinhibition. Considering all results, the commercial cultivar “Golden Delicious Reinders” was adversely affected by drought, while traditional cultivars exhibited better tolerance to drought stress.

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Transcriptome and physiological analysis of increase in drought stress tolerance by melatonin in tomato

10.21203/rs.3.rs-853632/v1 ◽

2021 ◽

Author(s):

Lu Yang ◽

Sijia Bu ◽

Shengxue Zhao ◽

Ning Wang ◽

Jiaxin Xiao ◽

...

Keyword(s):

Drought Stress ◽

Molecular Mechanisms ◽

Maximum Efficiency ◽

Photochemical Quenching ◽

Physiological Parameter ◽

Effective Quantum Yield ◽

Melatonin Treatment ◽

Tomato Cultivar ◽

Chlorophyll Fluorescence Parameters ◽

Psii Photochemistry

Abstract Drought stress seriously affects tomato growth, yield and quality. Previous reports have pointed out that melatonin (MT) can alleviate drought stress damage to tomato. To better understand the possible physiological and molecular mechanisms, chlorophyll fluorescence parameters and leaf transcriptome profiles were analyzed in the “Micro Tom” tomato cultivar with or without melatonin irrigation under normal and drought conditions. Polyethylene glycol 6000 (PEG6000) simulated continuous drought treatment reduced plant height, but melatonin treatment improved plant growth rate. Physiological parameter measurements revealed that the drought-induced decreases in maximum efficiency of photosystem II (PSII) photochemistry, the effective quantum yield of PSII, electron transfer rate, and photochemical quenching value caused by PEG6000 treatment were alleviated by melatonin treatment, which suggests a protective effect of melatonin on PSII. Comparative transcriptome analysis identified 447, 3982, 4526 and 3258 differentially expressed genes (DEGs) in the comparative groups plus-melatonin vs. minus-melatonin (no drought), drought vs. no drought (minus-melatonin), drought vs. no drought (melatonin) and plus-melatonin vs. minus-melatonin (drought), respectively. Furthermore, 101 DEGs were common to these four comparative groups. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed that DEGs in the four comparative groups were involved in multiple metabolic processes and closely related to hormone signal transduction and transcription factors. These results provide new insights into a probable mechanism of the melatonin-induced protection of photosynthesis and enhancement of drought tolerance in tomato plants.

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