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Plant Viral Disease Detection: From Molecular Diagnosis to Optical Sensing Technology—A Multidisciplinary Review. REMOTE SENSING 2022. [DOI: 10.3390/rs14071542] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Plant viral diseases result in productivity and economic losses to agriculture, necessitating accurate detection for effective control. Lab-based molecular testing is the gold standard for providing reliable and accurate diagnostics; however, these tests are expensive, time-consuming, and labour-intensive, especially at the field-scale with a large number of samples. Recent advances in optical remote sensing offer tremendous potential for non-destructive diagnostics of plant viral diseases at large spatial scales. This review provides an overview of traditional diagnostic methods followed by a comprehensive description of optical sensing technology, including camera systems, platforms, and spectral data analysis to detect plant viral diseases. The paper is organized along six multidisciplinary sections: (1) Impact of plant viral disease on plant physiology and consequent phenotypic changes, (2) direct diagnostic methods, (3) traditional indirect detection methods, (4) optical sensing technologies, (5) data processing techniques and modelling for disease detection, and (6) comparison of the costs. Finally, the current challenges and novel ideas of optical sensing for detecting plant viruses are discussed.
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Pérez-Bueno ML, Pineda M, Barón M. Phenotyping Plant Responses to Biotic Stress by Chlorophyll Fluorescence Imaging. FRONTIERS IN PLANT SCIENCE 2019; 10:1135. [PMID: 31620158 PMCID: PMC6759674 DOI: 10.3389/fpls.2019.01135] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 08/16/2019] [Indexed: 05/20/2023]
Abstract
Photosynthesis is a pivotal process in plant physiology, and its regulation plays an important role in plant defense against biotic stress. Interactions with pathogens and pests often cause alterations in the metabolism of sugars and sink/source relationships. These changes can be part of the plant defense mechanisms to limit nutrient availability to the pathogens. In other cases, these alterations can be the result of pests manipulating the plant metabolism for their own benefit. The effects of biotic stress on plant physiology are typically heterogeneous, both spatially and temporarily. Chlorophyll fluorescence imaging is a powerful tool to mine the activity of photosynthesis at cellular, leaf, and whole-plant scale, allowing the phenotyping of plants. This review will recapitulate the responses of the photosynthetic machinery to biotic stress factors, from pathogens (viruses, bacteria, and fungi) to pests (herbivory) analyzed by chlorophyll fluorescence imaging both at the lab and field scale. Moreover, chlorophyll fluorescence imagers and alternative techniques to indirectly evaluate photosynthetic traits used at field scale are also revised.
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Affiliation(s)
- María Luisa Pérez-Bueno
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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Barón M, Pineda M, Pérez-Bueno ML. Picturing pathogen infection in plants. ACTA ACUST UNITED AC 2017; 71:355-368. [PMID: 27626766 DOI: 10.1515/znc-2016-0134] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 07/22/2016] [Indexed: 11/15/2022]
Abstract
Several imaging techniques have provided valuable tools to evaluate the impact of biotic stress on host plants. The use of these techniques enables the study of plant-pathogen interactions by analysing the spatial and temporal heterogeneity of foliar metabolism during pathogenesis. In this work we review the use of imaging techniques based on chlorophyll fluorescence, multicolour fluorescence and thermography for the study of virus, bacteria and fungi-infected plants. These studies have revealed the impact of pathogen challenge on photosynthetic performance, secondary metabolism, as well as leaf transpiration as a promising tool for field and greenhouse management of diseases. Images of standard chlorophyll fluorescence (Chl-F) parameters obtained during Chl-F induction kinetics related to photochemical processes and those involved in energy dissipation, could be good stress indicators to monitor pathogenesis. Changes on UV-induced blue (F440) and green fluorescence (F520) measured by multicolour fluorescence imaging in pathogen-challenged plants seem to be related with the up-regulation of the plant secondary metabolism and with an increase in phenolic compounds involved in plant defence, such as scopoletin, chlorogenic or ferulic acids. Thermal imaging visualizes the leaf transpiration map during pathogenesis and emphasizes the key role of stomata on innate plant immunity. Using several imaging techniques in parallel could allow obtaining disease signatures for a specific pathogen. These techniques have also turned out to be very useful for presymptomatic pathogen detection, and powerful non-destructive tools for precision agriculture. Their applicability at lab-scale, in the field by remote sensing, and in high-throughput plant phenotyping, makes them particularly useful. Thermal sensors are widely used in crop fields to detect early changes in leaf transpiration induced by both air-borne and soil-borne pathogens. The limitations of measuring photosynthesis by Chl-F at the canopy level are being solved, while the use of multispectral fluorescence imaging is very challenging due to the type of light excitation that is used.
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Montero R, Pérez-Bueno ML, Barón M, Florez-Sarasa I, Tohge T, Fernie AR, Ouad HEA, Flexas J, Bota J. Alterations in primary and secondary metabolism in Vitis vinifera 'Malvasía de Banyalbufar' upon infection with Grapevine leafroll-associated virus 3. PHYSIOLOGIA PLANTARUM 2016; 157:442-52. [PMID: 26926417 DOI: 10.1111/ppl.12440] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 01/28/2016] [Indexed: 05/18/2023]
Abstract
Plant defense mechanisms against pathogens result in differential regulation of various processes of primary and secondary metabolism. Imaging techniques, such as fluorescence imaging and thermography, are very valuable tools providing spatial and temporal information about these processes. In this study, effects of Grapevine leafroll-associated virus 3 (GLRaV-3) on grapevine physiology were analyzed in pot-grown asymptomatic plants of the white cultivar Malvasía de Banyalbufar. The virus triggered changes in the activity of photosynthesis and secondary metabolism. There was a decrease in the photorespiratory intermediates glycine and serine in infected plants, possibly as a defense response against the infection. The content of malate, which plays an important role in plant metabolism, also decreased. These results correlate with the increased non-photochemical quenching found in infected plants. On the other hand, the concentration of flavonols (represented by myricetin, kaempferol and quercetin derivatives) and hydroxycinnamic acids (which include derivatives of caffeic acid) increased following infection by the virus. These compounds could be responsible for the increase in multicolor fluorescence F440 (blue fluorescence) and F520 (green fluorescence) on the leaves, and changes in the fluorescence parameters F440/F680, F440/F740, F520/F680, F520/F740 and F680/F740. The combined analysis of chlorophyll fluorescence kinetics and blue-green fluorescence emitted by phenolics could constitute disease signatures allowing the discrimination between GLRaV-3 infected and non-infected plants at very early stage of infection, prior to the development of symptoms.
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Affiliation(s)
- Rafael Montero
- Institut de Recerca i Formació Agrària i Pesquera (IRFAP), Palma de Mallorca, 07009, Spain
| | - María Luisa Pérez-Bueno
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, Spanish Council of Scientific Research (CSIC), Granada, 18008, Spain
| | - Matilde Barón
- Department of Biochemistry and Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, Spanish Council of Scientific Research (CSIC), Granada, 18008, Spain
| | - Igor Florez-Sarasa
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
| | - Takayuki Tohge
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam, 14476, Germany
| | | | - Hanan El Aou Ouad
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterrànies, Departament de Biologia, Universitat de les Illes Balears, Palma de Mallorca, 07071, Spain
| | - Jaume Flexas
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterrànies, Departament de Biologia, Universitat de les Illes Balears, Palma de Mallorca, 07071, Spain
| | - Josefina Bota
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterrànies, Departament de Biologia, Universitat de les Illes Balears, Palma de Mallorca, 07071, Spain
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Moustaka J, Moustakas M. Photoprotective mechanism of the non-target organism Arabidopsis thaliana to paraquat exposure. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2014; 111:1-6. [PMID: 24861926 DOI: 10.1016/j.pestbp.2014.04.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 04/15/2014] [Accepted: 04/21/2014] [Indexed: 05/20/2023]
Abstract
The response of photosystem II (PSII), of the non-target organism Arabidopsis thaliana, to paraquat (Pq) exposure was studied by chlorophyll fluorescence imaging. Effects of 1mM Pq application by spray on A. thaliana leaves were monitored as soon as 20min after application at the deposit areas of the droplets. A decline in the effective quantum yield of photochemical energy conversion in PSII (ΦPSII) was accompanied by an increase in the quantum yield for dissipation by down regulation in PSII (ΦNPQ). The concomitant decrease in the quantum yield of non-regulated energy loss in PSII (ΦNO) pointed out a quick effective photoprotection mechanism to Pq exposure. Even 1h after Pq spray, when the maximum Pq effect was observed, the decrease of electron transport rate (ETR) and the increase in non-photochemical quenching (NPQ) resulted to maintain almost the same redox state of quinone A (QA) as control plants. Thus, maximal photoprotection was achieved since NPQ was regulated in such a way that PSII reaction centers remained open. Arabidopsis plants were protected from Pq exposure, by increasing NPQ that dissipates light energy and decreases the efficiency of photochemical reactions of photosynthesis (down regulation of PSII) via the "water-water cycle". PSII photochemistry began to recover 4h after Pq exposure, and this was evident from the increase of ΦPSII, the simultaneous decrease of ΦNPQ, and the concomitant decrease of ΦNO. Yet, ETR began to increase, as well as the fraction of open PSII reaction centers.
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Affiliation(s)
- Julietta Moustaka
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece
| | - Michael Moustakas
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece.
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Lawson T, Davey PA, Yates SA, Bechtold U, Baeshen M, Baeshen N, Mutwakil MZ, Sabir J, Baker NR, Mullineaux PM. C3 photosynthesis in the desert plant Rhazya stricta is fully functional at high temperatures and light intensities. THE NEW PHYTOLOGIST 2014; 201:862-873. [PMID: 24164092 DOI: 10.1111/nph.12559] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 09/23/2013] [Indexed: 05/10/2023]
Abstract
The C3 plant Rhazya stricta is native to arid desert environment zones, where it experiences daily extremes of heat, light intensity (PAR) and high vapour pressure deficit (VPD). We measured the photosynthetic parameters in R. stricta in its native environment to assess the mechanisms that permit it to survive in these extreme conditions. Infrared gas exchange analysis examined diel changes in assimilation (A), stomatal conductance (gs ) and transpiration (E) on mature leaves of R. stricta. A/ci analysis was used to determine the effect of temperature on carboxylation capacity (Vc,max ) and the light- and CO2 -saturated rate of photosynthesis (Amax ). Combined chlorophyll fluorescence and gas exchange light response curve analysis at ambient and low oxygen showed that both carboxylation and oxygenation of Rubisco acted as the major sinks for the end products of electron transport. Physiological analysis in conjunction with gene expression analysis suggested that there are two isoforms of Rubisco activase which may provide an explanation for the ability of R. stricta to maintain Rubisco function at high temperatures. The potential to exploit this ability to cope with extreme temperatures is discussed in the context of future crop improvement.
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Affiliation(s)
- Tracy Lawson
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Phillip A Davey
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Steven A Yates
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Ulrike Bechtold
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
| | - Mohammed Baeshen
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Nabih Baeshen
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Mohammed Z Mutwakil
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Jamal Sabir
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Neil R Baker
- School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
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Lüttge U. Whole-Plant Physiology: Synergistic Emergence Rather Than Modularity. PROGRESS IN BOTANY 2013. [DOI: 10.1007/978-3-642-30967-0_6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Fiorani F, Rascher U, Jahnke S, Schurr U. Imaging plants dynamics in heterogenic environments. Curr Opin Biotechnol 2012; 23:227-35. [PMID: 22257752 DOI: 10.1016/j.copbio.2011.12.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 10/19/2011] [Accepted: 12/14/2011] [Indexed: 11/18/2022]
Abstract
Noninvasive imaging sensors and computer vision approaches are key technologies to quantify plant structure, physiological status, and performance. Today, imaging sensors exploit a wide range of the electromagnetic spectrum, and they can be deployed to measure a growing number of traits, also in heterogenic environments. Recent advances include the possibility to acquire high-resolution spectra by imaging spectroscopy and classify signatures that might be informative of plant development, nutrition, health, and disease. Three-dimensional (3D) reconstruction of surfaces and volume is of particular interest, enabling functional and mechanistic analyses. While taking pictures is relatively easy, quantitative interpretation often remains challenging and requires integrating knowledge of sensor physics, image analysis, and complex traits characterizing plant phenotypes.
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Affiliation(s)
- Fabio Fiorani
- Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich, Leo-Brandt-Straße, 52425 Jülich, Germany
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Sperdouli I, Moustakas M. Spatio-temporal heterogeneity in Arabidopsis thaliana leaves under drought stress. PLANT BIOLOGY (STUTTGART, GERMANY) 2012; 14:118-28. [PMID: 21972900 DOI: 10.1111/j.1438-8677.2011.00473.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Using chlorophyll (chl) fluorescence imaging, we studied the effect of mild (MiDS), moderate (MoDS) and severe (SDS) drought stress on photosystem II (PSII) photochemistry of 4-week-old Arabidopsis thaliana. Spatio-temporal heterogeneity in all chl fluorescence parameters was maintained throughout water stress. After exposure to drought stress, maximum quantum yield of PSII photochemistry (F(v)/F(m)) and quantum efficiency of PSII photochemistry (Φ(PSΙΙ)) decreased less in the proximal (base) than in the distal (tip) leaf. The chl fluorescence parameter F(v) /F(m) decreased less after MoDS than MiDS. Under MoDS, the antioxidant mechanism of A. thaliana leaves seemed to be sufficient in scavenging reactive oxygen species, as evident by the decreased lipid peroxidation, the more excitation energy dissipated by non-photochemical quenching (NPQ) and decreased excitation pressure (1-q(p)). Arabidopsis leaves appear to function normally under MoDS, but do not seem to have particular metabolic tolerance mechanisms under MiDS and SDS, as revealed by the level of lipid peroxidation and decreased quantum yield for dissipation after down-regulation in PSII (Φ(NPQ)), indicating that energy dissipation by down-regulation did not function and electron transport (ETR) was depressed. The simultaneous increased quantum yield of non-regulated energy dissipation (Φ(NO)) indicated that both the photochemical energy conversion and protective regulatory mechanism were insufficient. The non-uniform photosynthetic pattern under drought stress may reflect different zones of leaf anatomy and mesophyll development. The data demonstrate that the effect of different degrees of drought stress on A. thaliana leaves show spatio-temporal heterogeneity, implying that common single time point or single point leaf analyses are inadequate.
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Affiliation(s)
- I Sperdouli
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Pineda M, Olejníčková J, Cséfalvay L, Barón M. Tracking viral movement in plants by means of chlorophyll fluorescence imaging. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:2035-40. [PMID: 21820756 DOI: 10.1016/j.jplph.2011.06.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 06/13/2011] [Accepted: 06/13/2011] [Indexed: 05/04/2023]
Abstract
Many techniques have been applied to understand viral cell-to-cell movement in host plants, but little progress has been made in understanding viral vascular transport mechanisms. We propose the use of chlorophyll fluorescence imaging techniques, not only to diagnose the viral infection, but also to follow the movement of the virus through the vascular system and its subsequent spread into the leaves. In Nicotiana benthamiana plants, imaging of chlorophyll fluorescence parameters such as Ф(PSII) and NPQ proved useful to follow infections with Pepper mild mottle virus. The results demonstrate a correlation between changes in the chlorophyll fluorescence parameters and the viral distribution analyzed by tissue printing.
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Affiliation(s)
- Mónica Pineda
- Department of Biochemistry, Molecular and Cell Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, C/ Profesor Albareda, n° 1, C.P. 18008, Granada, Spain
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Rolfe SA, Scholes JD. Chlorophyll fluorescence imaging of plant-pathogen interactions. PROTOPLASMA 2010; 247:163-75. [PMID: 20814703 DOI: 10.1007/s00709-010-0203-z] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 08/15/2010] [Indexed: 05/22/2023]
Abstract
Chlorophyll fluorescence imaging provides a noninvasive, non-destructive method with which to measure heterogenous changes in photosynthetic metabolism in plants infected by pathogens. The availability of commercial imaging fluorimeters has helped make this technique available to the wider scientific community, but considerable care is needed, both in experimental design and in the interpretation of results, to make the most of this powerful analytical tool. The origins of changes in chlorophyll fluorescence yield are discussed and the use of conventional and novel combinatorial imaging approaches explored, together with complementary techniques such as thermal imaging. This review examines the use of chlorophyll fluorescence imaging as a method for the early detection of viral, bacterial and fungal infection, before symptoms are visible by eye, and also as a means with which to probe underlying pathogen-induced changes in host physiology in both compatible and incompatible interactions. The use of chlorophyll fluorescence imaging to study host physiology is greatly enhanced when the atmosphere around the leaf is manipulated and simultaneous measurements of gas exchange made: The cost to the host plant of different resistance mechanisms can be calculated, the fate of the products of photosynthetic electron transport determined and localised alterations in the source-sink status of host tissue visualised.
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Chaerle L, Lenk S, Leinonen I, Jones HG, Van Der Straeten D, Buschmann C. Multi-sensor plant imaging: Towards the development of a stress-catalogue. Biotechnol J 2009; 4:1152-67. [PMID: 19557794 DOI: 10.1002/biot.200800242] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Agricultural production is limited by a wide range of abiotic (e.g. drought, waterlogging) and biotic (pests, diseases and weeds) stresses. The impact of these stresses can be minimized by appropriate management actions such as irrigation or chemical pesticide application. However, further optimization requires the ability to diagnose and quantify the different stresses at an early stage. Particularly valuable information of plant stress responses is provided by plant imaging, i.e. non-contact sensing with spatial resolving power: (i) thermal imaging, detecting changes in transpiration rate and (ii) fluorescence imaging monitoring alterations in photosynthesis and other physiological processes. These can be supplemented by conventional video imagery for study of growth. An efficient early warning system would need to discriminate between different stressors. Given the wide range of sensors, and the association of specific plant physiological responses with changes at particular wavelengths, this goal seems within reach. This is based on the organization of the individual sensor results in a matrix that identifies specific signatures for multiple stress types. In this report, we first review the diagnostic effectiveness of different individual imaging techniques and then extend this to the multi-sensor stress-identification approach.
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Jansen M, Gilmer F, Biskup B, Nagel KA, Rascher U, Fischbach A, Briem S, Dreissen G, Tittmann S, Braun S, De Jaeger I, Metzlaff M, Schurr U, Scharr H, Walter A. Simultaneous phenotyping of leaf growth and chlorophyll fluorescence via GROWSCREEN FLUORO allows detection of stress tolerance in Arabidopsis thaliana and other rosette plants. FUNCTIONAL PLANT BIOLOGY : FPB 2009; 36:902-914. [PMID: 32688701 DOI: 10.1071/fp09095] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 08/03/2009] [Indexed: 05/27/2023]
Abstract
Stress caused by environmental factors evokes dynamic changes in plant phenotypes. In this study, we deciphered simultaneously the reaction of plant growth and chlorophyll fluorescence related parameters using a novel approach which combines existing imaging technologies (GROWSCREEN FLUORO). Three different abiotic stress situations were investigated demonstrating the benefit of this approach to distinguish between effects related to (1) growth, (2) chlorophyll-fluorescence, or (3) both of these aspects of the phenotype. In a drought stress experiment with more than 500 plants, poly(ADP-ribose) polymerase (PARP) deficient lines of Arabidopsis thaliana (L.) Heynh showed increased relative growth rates (RGR) compared with C24 wild-type plants. In chilling stress, growth of PARP and C24 lines decreased rapidly, followed by a decrease in Fv/Fm. Here, PARP-plants showed a more pronounced decrease of Fv/Fm than C24, which can be interpreted as a more efficient strategy for survival in mild chilling stress. Finally, the reaction of Nicotiana tabacum L. to altered spectral composition of the intercepted light was monitored as an example of a moderate stress situation that affects chlorophyll-fluorescence related, but not growth-related parameters. The examples investigated in this study show the capacity for improved plant phenotyping based on an automated and simultaneous evaluation of growth and photosynthesis at high throughput.
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Affiliation(s)
- Marcus Jansen
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Frank Gilmer
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Bernhard Biskup
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Kerstin A Nagel
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Uwe Rascher
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Andreas Fischbach
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Sabine Briem
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Georg Dreissen
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Susanne Tittmann
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Silvia Braun
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Iris De Jaeger
- Bayer BioScience N.V., Technologiepark 38, 9052 Gent, Belgium
| | | | - Ulrich Schurr
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Hanno Scharr
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Achim Walter
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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Pineda M, Gáspár L, Morales F, Szigeti Z, Barón M. Multicolor fluorescence imaging of leaves--a useful tool for visualizing systemic viral infections in plants. Photochem Photobiol 2008; 84:1048-60. [PMID: 18435702 DOI: 10.1111/j.1751-1097.2008.00357.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Multicolor fluorescence induced by UV light is a sensitive and specific tool that may be used to provide information about the primary and secondary metabolism of plants by monitoring signals of the chlorophyll fluorescence (Chl-F) and blue-green fluorescence (BGF), respectively. We have followed the systemic infection of Nicotiana benthamiana plants with the Pepper mild mottle virus (PMMoV) by means of a multicolor fluorescence-imaging system, to detect differences between two strains of PMMoV during the infection process and to establish a correlation between the virulence and changes induced in the host plant. Changes in both BGF and Chl-F were monitored. BGF increased mainly in the abaxial side of the leaf during pathogenesis and the corresponding images showed a clear vein-associated pattern in leaves of infected plants. HPLC analysis of leaf extracts was carried out to identify compounds emitting BGF, and determined that chlorogenic acid was one of the main contributors. BGF imaging was able to detect viral-induced changes in asymptomatic (AS) leaves before detection of the virus itself. Chl-F images confirmed our previous results of alterations in the photosynthetic apparatus of AS leaves from infected plants that were detected with other imaging techniques. Fluorescence ratios F440/F690 and F440/F740, which increase during pathogenesis, were excellent indicators of biotic stress.
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Affiliation(s)
- Mónica Pineda
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, Spanish Council for Scientific Research (CSIC), Granada, Spain
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TAKAYAMA K, SAKAI Y, NISHINA H, OMASA K. Chlorophyll Fluorescence Imaging at 77K for Assessing the Heterogeneously Distributed Light Stress Over a Leaf Surface. ACTA ACUST UNITED AC 2007. [DOI: 10.2525/ecb.45.39] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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16
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Berger S, Sinha AK, Roitsch T. Plant physiology meets phytopathology: plant primary metabolism and plant-pathogen interactions. JOURNAL OF EXPERIMENTAL BOTANY 2007; 58:4019-4026. [PMID: 18182420 DOI: 10.1111/j.1399-3054.2004.00433.x] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Phytopathogen infection leads to changes in secondary metabolism based on the induction of defence programmes as well as to changes in primary metabolism which affect growth and development of the plant. Therefore, pathogen attack causes crop yield losses even in interactions which do not end up with disease or death of the plant. While the regulation of defence responses has been intensively studied for decades, less is known about the effects of pathogen infection on primary metabolism. Recently, interest in this research area has been growing, and aspects of photosynthesis, assimilate partitioning, and source-sink regulation in different types of plant-pathogen interactions have been investigated. Similarly, phytopathological studies take into consideration the physiological status of the infected tissues to elucidate the fine-tuned infection mechanisms. The aim of this review is to give a summary of recent advances in the mutual interrelation between primary metabolism and pathogen infection, as well as to indicate current developments in non-invasive techniques and important strategies of combining modern molecular and physiological techniques with phytopathology for future investigations.
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Affiliation(s)
- Susanne Berger
- Julius-von-Sachs-Institut fuer Biowissenschaften, Universitaet Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany.
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Pérez-Bueno ML, Ciscato M, VandeVen M, García-Luque I, Valcke R, Barón M. Imaging viral infection: studies on Nicotiana benthamiana plants infected with the pepper mild mottle tobamovirus. PHOTOSYNTHESIS RESEARCH 2006; 90:111-23. [PMID: 17203361 DOI: 10.1007/s11120-006-9098-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Accepted: 08/18/2006] [Indexed: 05/04/2023]
Abstract
We have studied by kinetic Chl-fluorescence imaging (Chl-FI) Nicotiana benthamiana plants infected with the Italian strain of the pepper mild mottle tobamovirus (PMMoV-I). We have mapped leaf photosynthesis at different points of the fluorescence induction curve as well as at different post-infection times. Images of different fluorescence parameters were obtained to investigate which one could discriminate control from infected leaves in the absence of symptoms. The non-photochemical quenching (NPQ) of excess energy in photosystem II (PSII) seems to be the most adequate chlorophyll fluorescence parameter to assess the effect of tobamoviral infection on the chloroplast. Non-symptomatic mature leaves from inoculated plants displayed a very characteristic time-varying NPQ pattern. In addition, a correlation between NPQ amplification and virus localization by tissue-print was found, suggesting that an increase in the local NPQ values is associated with the areas invaded by the pathogen. Changes in chloroplast ultrastructure in non-symptomatic leaf areas showing different NPQ levels were also investigated. A gradient of ultrastructural modifications was observed among the different areas.
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Affiliation(s)
- María Luisa Pérez-Bueno
- Plant Biology Department, Centro Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain
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Chaerle L, Pineda M, Romero-Aranda R, Van Der Straeten D, Barón M. Robotized thermal and chlorophyll fluorescence imaging of pepper mild mottle virus infection in Nicotiana benthamiana. PLANT & CELL PHYSIOLOGY 2006; 47:1323-36. [PMID: 16943218 DOI: 10.1093/pcp/pcj102] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
After infecting a susceptible host, pathogens spread throughout the plant. Depending on pathogen type and strain, the severity of symptoms varies greatly. In the case of pepper mild mottle virus (PMMoV) infection in Nicotiana benthamiana, newly developing leaves display visual symptoms (symptomatic leaves). In this study, two PMMoV strains were used, the Spanish strain (PMMoV-S) being more virulent than the Italian strain (PMMoV-I). Plants infected with PMMoV-I could recover from the virus-induced symptoms. Leaves that were fully developed at the start of PMMoV infection remained symptomless. In these asymptomatic leaves, an increase in temperature, initiating from the tissue adjacent to the main veins, was observed 7 d before the Chl fluorescence pattern changed. Virus immunolocalization on tissue prints matched well with the concomitant pattern of Chl fluorescence increase. The temperature increase, associated with the veins, was shown to be related to stomatal closure. Upon PMMoV-I infection, the appearance of thermal and Chl fluorescence symptoms as well as virus accumulation were delayed by 3 d compared with PMMoV-S-induced symptoms. The temperature increase of whole symptomatic leaves was also correlated with a decrease in stomatal aperture. In contrast to the persistent increase in symptomatic leaf temperature observed during PMMoV-S infection, the temperature of symptomatic leaves of PMMoV-I-infected plants decreased gradually during recovery. We propose that the earliest temperature increase is caused by a systemic plant response to the virus infection, involving the control of water loss. In conclusion, thermography has potential as an early reporter of an ongoing compatible infection process.
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Affiliation(s)
- Laury Chaerle
- Unit of Plant Hormone Signaling and Bioimaging, Ghent University, K. L. Ledeganckstraat 35, B-9000 Gent, Belgium
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19
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Aldea M, Hamilton JG, Resti JP, Zangerl AR, Berenbaum MR, Frank TD, Delucia EH. Comparison of photosynthetic damage from arthropod herbivory and pathogen infection in understory hardwood saplings. Oecologia 2006; 149:221-32. [PMID: 16758220 DOI: 10.1007/s00442-006-0444-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Accepted: 04/20/2006] [Indexed: 10/24/2022]
Abstract
Arthropods and pathogens damage leaves in natural ecosystems and may reduce photosynthesis at some distance away from directly injured tissue. We quantified the indirect effects of naturally occurring biotic damage on leaf-level photosystem II operating efficiency (Phi(PSII)) of 11 understory hardwood tree species using chlorophyll fluorescence and thermal imaging. Maps of fluorescence parameters and leaf temperature were stacked for each leaf and analyzed using a multivariate method adapted from the field of quantitative remote sensing. Two tree species, Quercus velutina and Cercis canadensis, grew in plots exposed to ambient and elevated atmospheric CO(2) and were infected with Phyllosticta fungus, providing a limited opportunity to examine the potential interaction of this element of global change and biotic damage on photosynthesis. Areas surrounding damage had depressed Phi(PSII )and increased down-regulation of PSII, and there was no evidence of compensation in the remaining tissue. The depression of Phi(PSII) caused by fungal infections and galls extended >2.5 times further from the visible damage and was approximately 40% more depressed than chewing damage. Areas of depressed Phi(PSII) around fungal infections on oaks growing in elevated CO(2) were more than 5 times larger than those grown in ambient conditions, suggesting that this element of global change may influence the indirect effects of biotic damage on photosynthesis. For a single Q. velutina sapling, the area of reduced Phi(PSII) was equal to the total area directly damaged by insects and fungi. Thus, estimates based only on the direct effect of biotic agents may greatly underestimate their actual impact on photosynthesis.
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Affiliation(s)
- Mihai Aldea
- Program in Ecology and Evolutionary Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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Swarbrick PJ, Schulze-Lefert P, Scholes JD. Metabolic consequences of susceptibility and resistance (race-specific and broad-spectrum) in barley leaves challenged with powdery mildew. PLANT, CELL & ENVIRONMENT 2006; 29:1061-76. [PMID: 17080933 DOI: 10.1111/j.1365-3040.2005.01472.x] [Citation(s) in RCA: 179] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In a compatible interaction biotrophic fungi often lower the yield of their hosts by reducing photosynthesis and altering the fluxes of carbon within the infected leaf. In contrast, comparatively little is known about the metabolic consequences of activating resistance responses. In this study we investigated the hypothesis that the activation of both race-specific (Mla12) and broad-spectrum (mlo) resistance pathways in barley leaves infected with Blumeria graminis represents a cost to the plant in terms of carbon production and utilization. We have shown, using quantitative imaging of chlorophyll fluorescence, that during a susceptible interaction, photosynthesis was progressively reduced both in cells directly below fungal colonies and in adjacent cells when compared with uninoculated leaves. The lower rate of photosynthesis was associated with an increase in invertase activity, an accumulation of hexoses and a down-regulation of photosynthetic gene expression. During both Mla12- and mlo-mediated resistance, photosynthesis was also reduced, most severely inhibited in cells directly associated with attempted penetration of the fungus but also in surrounding cells. These cells displayed intense autofluorescence under ultraviolet illumination indicative of the accumulation of phenolic compounds and/or callose deposition. The depression in photosynthesis was not due only to cell death but also to an alteration in source-sink relations and carbon utilization. Apoplastic (cell wall-bound) invertase activity increased more rapidly and to a much greater extent than in infected susceptible leaves and was accompanied by an accumulation of hexoses that was localized to areas of the leaf actively exhibiting resistance responses. The accumulation of hexoses was accompanied by a down-regulation in the expression of Rubisco (rbcS) and chlorophyll a/b binding protein (cab) genes (although to a lesser extent than in a compatible interaction) and with an up-regulation in the expression of the pathogenesis-related protein 1 (PR-1). These results are consistent with a role for invertase in the generation of hexoses, which may supply energy for defence reactions and/or act as signals inducing defence gene expression.
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Affiliation(s)
- Philip J Swarbrick
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
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Schurr U, Walter A, Rascher U. Functional dynamics of plant growth and photosynthesis--from steady-state to dynamics--from homogeneity to heterogeneity. PLANT, CELL & ENVIRONMENT 2006; 29:340-52. [PMID: 17080590 DOI: 10.1111/j.1365-3040.2005.01490.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Plants are much more dynamic than we usually expect them to be. This dynamic behaviour is of paramount importance for their performance under natural conditions, when resources are distributed heterogeneously in space and time. However, plants are not only the cue ball of their physical and chemical environment. Endogenous rhythms and networks controlling photosynthesis and growth buffer plant processes from external fluctuations. This review highlights recent evidence of the importance of dynamic temporal and spatial organization of photosynthesis and of growth in leaves and roots. These central processes for plant performance differ strongly in their dependence on environmental impact and endogenous properties, respectively. Growth involves a wealth of processes ranging from the supply of resources from external and internal sources to the growth processes themselves. In contrast, photosynthesis can only take place when light and CO2 are present and thus clearly requires 'input from the environment'. Nevertheless, growth and photosynthesis are connected to each other via mechanisms that are still not fully understood. Recent advances in imaging technology have provided new insights into the dynamics of plant-environment interactions. Such processes do not only play a crucial role in understanding stress response of plants under extreme environmental conditions. Dynamics of plants under modest growth conditions rise from endogenous mechanisms as well as exogenous impact too. It is thus an important task for future research to identify how dynamic external conditions interact with plant-internal signalling networks to optimize plant behaviour in real time and to understand how plants have adapted to characteristic spatial and temporal properties of the resources from their environment, on which they depend on.
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Affiliation(s)
- U Schurr
- ICG-III (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
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22
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Funayama-Noguchi S, Terashima I. Effects of Eupatorium yellow vein virus infection on photosynthetic rate, chlorophyll content and chloroplast structure in leaves of Eupatorium makinoi during leaf development. FUNCTIONAL PLANT BIOLOGY : FPB 2006; 33:165-175. [PMID: 32689223 DOI: 10.1071/fp05172] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 10/05/2005] [Indexed: 06/11/2023]
Abstract
Infection of Eupatorium yellow vein geminivirus (EpYVV, formerly called tobacco leaf curl virus, TLCV) causes variegation in Eupatorium makinoi Kawahara et Yahara leaves. We examined changes in photosynthesis during leaf development to clarify what is the primary event when photosynthesis is suppressed in virus-infected E. makinoi leaves. The gas-exchange rate, leaf absorptance, chlorophyll (Chl) and nitrogen contents, leaf anatomy and chloroplast ultrastructure were compared between virus-infected and uninfected E. makinoi leaves at various developmental stages. These photosynthetic properties did not differ between infected and uninfected leaves when they were young. However, when expanded, infected leaves showed lower maximum quantum yield of photosynthetic CO2 uptake in the incident photosynthetically active photon fluence rate (PPFR), which was attributed to their lower Chl contents. The Chla / b ratio was higher and the grana had fewer thylakoids in the infected leaves, which are features common to Chl b-deficient mutants that have defects in Chl synthesis. Our results suggested that, in E. makinoi leaves, EpYVV infection primarily impairs Chl biosynthesis. Possible mechanisms of the suppression of photosynthesis in E. makinoi leaves by virus infection are discussed.
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Affiliation(s)
- Sachiko Funayama-Noguchi
- Department of Biology, Graduate School of Science, Osaka University, Machikaneyama-cho 1-1, Toyonaka, Osaka 560-0043, Japan
| | - Ichiro Terashima
- Department of Biology, Graduate School of Science, Osaka University, Machikaneyama-cho 1-1, Toyonaka, Osaka 560-0043, Japan
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Walter A, Rascher U, Osmond B. Transitions in photosynthetic parameters of midvein and interveinal regions of leaves and their importance during leaf growth and development. PLANT BIOLOGY (STUTTGART, GERMANY) 2004; 6:184-91. [PMID: 15045670 DOI: 10.1055/s-2004-817828] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The areal development of photosynthetic efficiency and growth patterns in expanding leaves of two different dicotyledonous species - Coccoloba uvifera and Sanchezia nobilis - was investigated by imaging both processes repeatedly over 32 days. Measurements were performed using combined imaging systems for chlorophyll fluorescence and growth, with the same spatial resolution. Significant differences in potential quantum yield of photosynthesis (F (v)/F (m)), a parameter indicating the functional status of photosystem II, were found between midvein and interveinal tissue. Although base-tip gradients and spatial patchiness were observed in the distribution of relative growth rate, neither midvein nor interveinal tissue showed such patterns in F (v)/F (m). In young leaves, F (v)/F (m) of the midvein was higher than F (v)/F (m) of interveinal tissue. This difference declined gradually with time, and upon cessation of growth, F (v)/F (m) of interveinal regions exceeded those of midvein tissue. Images of chlorophyll fluorescence quenching showed that DeltaF/F (m)' in the different tissues correlated with F (v)/F (m), indicating that, in these uniformly illuminated leaves, transitions in photosynthetic electron transport activity follow those of predawn quantum efficiency. We explore the implications of these observations during leaf development, discuss effects of sucrose delivery from veins to interveinal areas on relative rates of photosynthetic development in these tissues, and propose that the initially higher photosynthetic activity in the midvein compared to the intervein tissues may supply carbohydrates and energy for leaf growth processes.
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Affiliation(s)
- A Walter
- Biosphere 2 Center, Columbia University, P.O. Box 689, Oracle, AZ 85623, USA.
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Omasa K, Takayama K. Simultaneous Measurement of Stomatal Conductance, Non-photochemical Quenching, and Photochemical Yield of Photosystem II in Intact Leaves by Thermal and Chlorophyll Fluorescence Imaging. ACTA ACUST UNITED AC 2003; 44:1290-300. [PMID: 14701924 DOI: 10.1093/pcp/pcg165] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A new imaging system capable of simultaneously measuring stomatal conductance and fluorescence parameters, non-photochemical quenching (NPQ) and photochemical yield of photosystem II (Phi(PSII)), in intact leaves under aerobic conditions by both thermal imaging and chlorophyll fluorescence imaging was developed. Changes in distributions of stomatal conductance and fluorescence parameters across Phaseolus vulgaris L. leaves induced by abscisic acid treatment were analyzed. A decrease in stomatal conductance expanded in all directions from the treatment site, then mainly spread along the lateral vein toward the leaf edge, depending on the ABA concentration gradient and the transpiration stream. The relationships between stomatal conductance and fluorescence parameters depended on the actinic light intensity, i.e. NPQ was greater and Phi(PSII) was lower at high light intensity. The fluorescence parameters did not change, regardless of stomatal closure levels at a photosynthetically active photon flux (PPF) of 270 micro mol m(-2) s(-1); however, they drastically changed at PPF values of 350 and 700 micro mol m(-2) s(-1), when the total stomatal conductance decreased to less than 80 and 200 mmol m(-2) s(-1), respectively. This study has, for the first time, quantitatively analyzed relationships between spatiotemporal variations in stomatal conductance and fluorescence parameters in intact leaves under aerobic conditions.
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Affiliation(s)
- Kenji Omasa
- Department of Biological and Environmental Engineering, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8675 Japan.
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West JS, Bravo C, Oberti R, Lemaire D, Moshou D, McCartney HA. The potential of optical canopy measurement for targeted control of field crop diseases. ANNUAL REVIEW OF PHYTOPATHOLOGY 2003; 41:593-614. [PMID: 12730386 DOI: 10.1146/annurev.phyto.41.121702.103726] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
There is increasing pressure to reduce the use of pesticides in modern crop production to decrease the environmental impact of current practice and to lower production costs. It is therefore imperative that sprays are only applied when and where needed. Since diseases in fields are frequently patchy, sprays may be applied unnecessarily to disease-free areas. Disease control could be more efficient if disease patches within fields could be identified and spray applied only to the infected areas. Recent developments in optical sensor technology have the potential to enable direct detection of foliar disease under field conditions. This review assesses recent developments in the use of optical methods for detecting foliar disease, evaluates the likely benefits of spatially selective disease control in field crops, and discusses practicalities and limitations of using optical disease detection systems for crop protection in precision pest management.
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Affiliation(s)
- Jonathan S West
- Plant Pathogen Interactions Division, Rothamsted Research, Harpenden, AL5 2JQ, United Kingdom.
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Beck F, Blasius B, Lüttge U, Neff R, Rascher U. Stochastic noise interferes coherently with a model biological clock and produces specific dynamic behaviour. Proc Biol Sci 2001; 268:1307-13. [PMID: 11410159 PMCID: PMC1088742 DOI: 10.1098/rspb.2001.1655] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The influence of noise is unavoidable in all living systems. Its impact on a model of a biological clock, normally running in regular oscillating modes, is examined. It is shown that in a specific system in which endogenous rhythmicity is produced by a beat oscillator acting on a feedback coupled metabolic pool system, noise can act coherently to produce unexpected dynamic behaviour, running from regular over pseudo-regular to irregular time-structures. If the biological system consists of a set of identical weakly coupled cells, stochasticity may lead to phase decoupling producing irregular spatio-temporal patterns. Synchronization via phase resetting can be achieved by external short-time temperature pulses. Explicit results are obtained for the well-studied circadian photosynthesis oscillations in plants performing crassulacean acid metabolism. Because of the generic structure of the underlying nonlinear dynamics they can, however, be regarded as a general property of the influence of noise on nonlinear excitable systems with fixed points occuring close to limit cycles.
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Affiliation(s)
- F Beck
- Institute of Nuclear Physics, Department of Physics, Darmstadt University of Technology, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany
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Almási A, Harsányi A, Gáborjányi R. Photosynthetic Alterations of Virus Infected Plants. ACTA ACUST UNITED AC 2001. [DOI: 10.1556/aphyt.36.2001.1-2.3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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28
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Chaerle L, Van Der Straeten D. Imaging techniques and the early detection of plant stress. TRENDS IN PLANT SCIENCE 2000; 5:495-501. [PMID: 11077259 DOI: 10.1016/s1360-1385(00)01781-7] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- L Chaerle
- Dept of Molecular Genetics, Ghent University, Belgium
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