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1. Plant density modifies root system architecture in spring barley (Hordeum vulgare L.) through a change in nodal root number

Author:
Rascher, U.,   et al.   ; Hecht, V. L.; Temperton, V. M.; Nagel, K. A.; Pude, R.; Postma, Johannes A.;     Show all 6 Authors
Source:
Plant and soil 2019 v.439 no.1-2 pp. 179-200
ISSN:
0032-079X
Subject:
Hordeum vulgare; branching; cultivars; field experimentation; fine roots; ideotypes; plant density; root crown; root growth; root systems; sowing; spring barley; topsoil
Abstract:
... AIM: Previously, we showed that sowing density influences root length density (RLD), specific root length (SRL) especially in the topsoil, and shallowness of fine roots of field grown spring barley (Hordeum vulagre L.). Here, we ask which trait components may explain these observed changes. METHOD: We grew two spring barley cultivars at contrasting sowing densities in both field trials and rhizotr ...
DOI:
10.1007/s11104-018-3764-9

2. Phenological analysis of unmanned aerial vehicle based time series of barley imagery with high temporal resolution

Author:
Rascher, U.,   et al.   ; Burkart, A.; Hecht, V.L.; Kraska, T.;     Show all 4 Authors
Source:
Precision agriculture 2018 v.19 no.1 pp. 134-146
ISSN:
1385-2256
Subject:
aerial photography; barley; case studies; corn; crop management; cultivars; developmental stages; experimental design; field experimentation; flight; germination; harvesting; phenology; phenotype; precision agriculture; ripening; seasonal development; soil; sowing; time series analysis; unmanned aerial vehicles; vegetative growth
Abstract:
... Emerging strategies and technologies in agriculture, such as precision farming and phenotyping depend on detailed data on all stages of crop development. Unmanned aerial vehicles promise to deliver such time series as they allow very frequent measurements. In this study, we analyse a field trial with two barley cultivars and two contrasting sowing densities in a random plot design over 2 consecuti ...
DOI:
10.1007/s11119-017-9504-y

3. Linking photosynthesis and sun-induced fluorescence at sub-daily to seasonal scales

Author:
Rascher, U.,   et al.   ; Wieneke, S.; Burkart, A.; Cendrero-Mateo, M.P.; Julitta, T.; Rossini, M.; Schickling, A.; Schmidt, M.;     Show all 8 Authors
Source:
Remote sensing of environment 2018 v.219 pp. 247-258
ISSN:
0034-4257
Subject:
canopy; carbon dioxide; chlorophyll; drought; eddy covariance; environmental factors; fluorescence; gross primary productivity; growing season; photochemistry; photosynthesis; radiation use efficiency; reflectance; remote sensing; seasonal variation; spectrometers; sugar beet; time series analysis; variance; vegetation index; water stress
Abstract:
... Due to its close link to the photosynthetic process, sun-induced chlorophyll fluorescence (F) opens new possibilities to study dynamics of photosynthetic light reactions and to quantify CO2 assimilation rates. Although recent studies show that F is linearly related to gross primary production (GPP) on coarse spatial and temporal scales, it is argued that this relationship may be mainly driven by s ...
DOI:
10.1016/j.rse.2018.10.019

4. Remote sensing of plant-water relations: An overview and future perspectives

Author:
Rascher, U.,   et al.   ; Damm, A.; Paul-Limoges, E.; Haghighi, E.; Simmer, C.; Morsdorf, F.; Schneider, F.D.; van der Tol, C.; Migliavacca, M.;     Show all 9 Authors
Source:
Journal of plant physiology 2018 v.227 pp. 3-19
ISSN:
0176-1617
Subject:
carbon cycle; energy balance; hydrologic cycle; mechanistic models; monitoring; photosynthesis; prediction; radiative transfer; remote sensing; simulation models; soil; transpiration; vegetation
Abstract:
... Vegetation is a highly dynamic component of the Earth surface and substantially alters the water cycle. Particularly the process of oxygenic plant photosynthesis determines vegetation connecting the water and carbon cycle and causing various interactions and feedbacks across Earth spheres. While vegetation impacts the water cycle, it reacts to changing water availability via functional, biochemica ...
DOI:
10.1016/j.jplph.2018.04.012

5. Unsupervised domain adaptation for early detection of drought stress in hyperspectral images

Author:
Rascher, U.,   et al.   ; Schmitter, P.; Steinrücken, J.; Römer, C.; Ballvora, A.; Léon, J.; Plümer, L.;     Show all 7 Authors
Source:
ISPRS journal of photogrammetry and remote sensing 2017 v.131 pp. 65-76
ISSN:
0924-2716
Subject:
biomass; data collection; environmental factors; genotype; hyperspectral imagery; lighting; models; plant diseases and disorders; support vector machines; water stress
Abstract:
... Hyperspectral images can be used to uncover physiological processes in plants if interpreted properly. Machine Learning methods such as Support Vector Machines (SVM) and Random Forests have been applied to estimate development of biomass and detect and predict plant diseases and drought stress. One basic requirement of machine learning implies, that training and testing is done in the same domain ...
DOI:
10.1016/j.isprsjprs.2017.07.003

6. Airborne based spectroscopy of red and far-red sun-induced chlorophyll fluorescence: Implications for improved estimates of gross primary productivity

Author:
Rascher, U.,   et al.   ; Wieneke, S.; Ahrends, H.; Damm, A.; Pinto, F.; Stadler, A.; Rossini, M.;     Show all 7 Authors
Source:
Remote sensing of environment 2016 v.184 pp. 654-667
ISSN:
0034-4257
Subject:
chlorophyll; fluorescence; image analysis; models; photosynthesis; plant adaptation; plant stress; primary productivity; reflectance; remote sensing; spectrometers; spectroscopy; vegetation; vegetation index; water shortages
Abstract:
... Remote sensing (RS) approaches commonly applied to constrain estimates of gross primary production (GPP) employ greenness-based vegetation indices derived from surface reflectance data. Such approaches cannot capture dynamic changes of photosynthesis rates as caused by environmental stress. Further, applied vegetation indices are often affected by background reflectance or saturation effects. Sun. ...
DOI:
10.1016/j.rse.2016.07.025

7. Continuous and long-term measurements of reflectance and sun-induced chlorophyll fluorescence by using novel automated field spectroscopy systems

Author:
Rascher, U.,   et al.   ; Cogliati, S.; Rossini, M.; Julitta, T.; Meroni, M.; Schickling, A.; Burkart, A.; Pinto, F.; Colombo, R.;     Show all 9 Authors
Source:
Remote sensing of environment 2015 v.164 pp. 270-281
ISSN:
0034-4257
Subject:
canopy; chlorophyll; crops; data collection; ecosystems; fluorescence; monitoring; plant growth; reflectance; remote sensing; reproduction; spectral analysis; spectrometers; spectroscopy; superoxide anion; vegetation; vegetation index
Abstract:
... In this paper we present novel automated field spectroscopy systems for collecting unattended, continuous and long-term measurements of plant canopies and, more in general, of Earth's ecosystems. These systems simultaneously collect high and ultra-high resolution spectra in the visible to near-infrared (VNIR) domain employing two spectrometers: i) the first covers the spectral range 400–1000nm wit ...
DOI:
10.1016/j.rse.2015.03.027

8. FLD-based retrieval of sun-induced chlorophyll fluorescence from medium spectral resolution airborne spectroscopy data

Author:
Rascher, U.,   et al.   ; Damm, A.; Guanter, L.; Laurent, V.C.E.; Schaepman, M.E.; Schickling, A.;     Show all 6 Authors
Source:
Remote sensing of environment 2014 v.147 pp. 256-266
ISSN:
0034-4257
Subject:
absorption; aircraft; altitude; chlorophyll; flight; fluorescence; guidelines; oxygen; photosynthesis; remote sensing; spectral analysis; spectrometers; spectroscopy; superoxide anion
Abstract:
... Sun-induced chlorophyll fluorescence (Fs) is the radiation flux emitted from chlorophyll molecules and can be used as a remote sensing (RS) observable to be linked to plant photosynthesis. Recently, significant progress has been made to quantify Fs from RS data, but both retrieval and interpretation of Fs remain challenging. In the case of airborne sensors with a medium spectral resolution (<2–4nm ...
DOI:
10.1016/j.rse.2014.03.009

9. Dynamics of photosynthesis in fluctuating light

Author:
Rascher, U.,   et al.   ; Nedbal, L.;     Show all 2 Author
Source:
Current opinion in plant biology 2006 v.9 no.6 pp. 671-678
ISSN:
1369-5266
Subject:
temporal variation; photosynthesis; plant physiology; light intensity
DOI:
10.1016/j.pbi.2006.09.012
PubMed:
17011815

10. Vertical gradient in soil temperature stimulates development and increases biomass accumulation in barley

Author:
RASCHER, U.,   et al.   ; FÜLLNER, K.; TEMPERTON, V. M.; JAHNKE, S.; RIST, R.; SCHURR, U.; KUHN, A. J.;     Show all 7 Authors
Source:
Plant, cell and environment 2012 v.35 no.5 pp. 884-892
ISSN:
0140-7791
Subject:
barley; biomass production; greenhouse experimentation; nitrogen content; root systems; roots; seedlings; shoots; soil temperature; temperature profiles
Abstract:
... We have detailed knowledge from controlled environment studies on the influence of root temperature on plant performance, growth and morphology. However, in all studies root temperature was kept spatially uniform, which motivated us to test whether a vertical gradient in soil temperature affected development and biomass production. Roots of barley seedlings were exposed to three uniform temperatur ...
DOI:
10.1111/j.1365-3040.2011.02460.x
PubMed:
22070728

11. Functional dynamics of plant growth and photosynthesis - from steady-state to dynamics - from homogeneity to heterogeneity

Author:
Rascher, U.,   et al.   ; Schurr, U.; Walter, A.;     Show all 3 Authors
Source:
Plant, cell and environment 2006 v.29 no.3 pp. 340-352
ISSN:
0140-7791
Subject:
carbon dioxide; environmental factors; environmental impact; leaves; photosynthesis; plant growth; roots; space and time; stress response
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 pro ...
DOI:
10.1111/j.1365-3040.2005.01490.x
PubMed:
17080590

12. Sun‐induced fluorescence – a new probe of photosynthesis: First maps from the imaging spectrometer HyPlant

Author:
Rascher, U.,   et al.   ; Alonso, L.; Burkart, A.; Cilia, C.; Cogliati, S.; Colombo, R.; Damm, A.; Drusch, M.; Guanter, L.; Hanus, J.; Hyvärinen, T.; Julitta, T.; Jussila, J.; Kataja, K.; Kokkalis, P.; Kraft, S.; Kraska, T.; Matveeva, M.; Moreno, J.; Muller, O.; Panigada, C.; Pikl, M.; Pinto, F.; Prey, L.; Pude, R.; Rossini, M.; Schickling, A.; Schurr, U.; Schüttemeyer, D.; Verrelst, J.; Zemek, F.;     Show all 31 Authors
Source:
Global change biology 2015 v.21 no.12 pp. 4673-4684
ISSN:
1354-1013
Subject:
absorption; carbon dioxide; chlorophyll; field experimentation; fluorescence; functional status; image analysis; monitoring; photosynthesis; photosynthetically active radiation; plant stress; prediction; reflectance; remote sensing; seasonal variation; spectral analysis; spectrometers; spectroscopy; uncertainty; vegetation types
Abstract:
... Variations in photosynthesis still cause substantial uncertainties in predicting photosynthetic CO₂ uptake rates and monitoring plant stress. Changes in actual photosynthesis that are not related to greenness of vegetation are difficult to measure by reflectance based optical remote sensing techniques. Several activities are underway to evaluate the sun‐induced fluorescence signal on the ground an ...
DOI:
10.1111/gcb.13017

13. Assessing photosynthetic efficiency in an experimental mangrove canopy using remote sensing and chlorophyll fluorescence

Author:
Rascher, U.,   et al.   ; Nichol, C.J.; Matsubara, S.; Osmond, B.;     Show all 4 Authors
Source:
Trees 2006 v.20 no.1 pp. 9-15
ISSN:
0931-1890
Subject:
photosynthesis; mangrove forests; chlorophyll; fluorescence; xanthophylls; photochemistry; Rhizophora mangle; Avicennia germinans; overstory; canopy; reflectance; equations; diurnal variation; tree physiology; monitoring; nondestructive methods
Abstract:
... This study examined the ability of the photochemical reflectance index (PRI) to track changes in effective quantum yield (Δ F/F m '), non-photochemical quenching (NPQ), and the xanthophyll cycle de-epoxidation (DPS) in an experimental mangrove canopy. PRI was correlated with (Δ F/F m ') and NPQ over the 4-week measurement period and over the diurnal cycle. The normalised difference vegetation inde ...
DOI:
10.1007/s00468-005-0005-7

14. Nitrogen input by cyanobacterial biofilms of an inselberg into a tropical rainforest in French Guiana

Author:
Rascher, U.,   et al.   ; Dojani, S.; Lakatos, M.; Wanek, W.; Luttge, U.; Budel, B.;     Show all 6 Authors
Source:
Flora 2007 v.202 no.7 pp. 521-529
ISSN:
0367-2530
Subject:
tropical rain forests; rocks; biofilm; Cyanobacteria; nitrogen; biogeochemical cycles; soil fertility; habitats; stable isotopes; losses from soil; soil chemistry; French Guiana
Abstract:
... Inselbergs are isolated rock outcrops displaying high heterogeneity in both soil formation and microclimatic condition with high variation in plant biodiversity. Vegetation patterns on inselbergs in the humid tropics range from rocks covered with dense biofilms predominated by cyanobacteria to high forest on deep soils. Along a similar transect, we investigated N supply to the vegetation using ele ...
DOI:
10.1016/j.flora.2006.12.001

15. Evaluation of instant light-response curves of chlorophyll fluorescence parameters obtained with a portable chlorophyll fluorometer on site in the field

Author:
Rascher, U.,   et al.   ; Liebig, M.; Luttge, U.;     Show all 3 Authors
Source:
Plant, cell and environment 2000 v.23 no.12 pp. 1397-1405
ISSN:
0140-7791
Subject:
equipment; calibration; fluorescence; Rubus plicatus; light intensity; photosystem II; leaves; field experimentation; measurement; chlorophyll; Germany
DOI:
10.1046/j.1365-3040.2000.00650.x

16. Remote sensing of heterogeneity in photosynthetic efficiency, electron transport and dissipation of excess light in Populus deltoides stands under ambient and elevated CO2 concentrations, and in a tropical forest canopy, using a new laser-induced fluorescence transient device

Author:
Rascher, U.,   et al.   ; Anayev, G.; Kolber, Z.S.; Klimov, D.; Falkowski, P.G.; Berry, J.A.; Martin, R.; Osmond, B.;     Show all 8 Authors
Source:
Global change biology 2005 v.11 no.8 pp. 1195-1206
ISSN:
1354-1013
Subject:
carbon dioxide; forest trees; lasers; Inga (Fabaceae); fluorescence; Populus deltoides; electron transfer; photosystem II; Pterocarpus; elevated atmospheric gases; remote sensing; chlorophyll; leaves; greenhouses
DOI:
10.1111/j.1365-2486.2005.00988.x

17. The effect of elevated CO2 on diel leaf growth cycle, leaf carbohydrate content and canopy growth performance of Populus deltoides

Author:
Rascher, U.,   et al.   ; Walter, A.; Christ, M.M.; Barron-Gafford, G.A.; Grieve, K.A.; Murthy, R.;     Show all 6 Authors
Source:
Global change biology 2005 v.11 no.8 pp. 1207-1219
ISSN:
1354-1013
Subject:
tree growth; carbon dioxide; carbohydrate metabolism; canopy; glucose; carbohydrate content; Populus deltoides; starch; leaf area; elevated atmospheric gases; diurnal variation; leaf development; greenhouses
DOI:
10.1111/j.1365-2486.2005.00990.x

18. Ecophysiology of niche occupation by two giant rosette plants, Lobelia gibberoa Hemsl and Solanecio gigas (Vatke) C. Jeffrey, in an afromontane forest valley

Author:
Rascher, U.,   et al.   ; Luttge, U.; Fetene, M.; Liebig, M.; Beck, E.;     Show all 5 Authors
Source:
Annals of botany 2001 v.88 no.2 pp. 267-278
ISSN:
0305-7364
Subject:
chlorophyll; montane forests; spatial distribution; fluorescence; leaf area index; plant characteristics; microhabitats; height; Lobelia; plant density; photosynthesis; plant vascular system; plant morphology; leaf conductance; Ethiopia
Abstract:
... The niche occupation of two giant rosette plants, Lobelia gibberoa Hemsl and Solanecio gigas (Vatke) C. Jeffrey, was investigated in a small mountain valley in an afromontane forest, central Ethiopia. Plant distribution, density, life-form, morphology and microsite conditions were related to transpiration, chlorophyll a fluorescence and delta13C analysis to explain how ecophysiological traits and ...
DOI:
10.1006/anbo.2001.1450

19. Responses to different external light rhythms by the circadian rhythm of Crassulacean acid metabolism in Kalanchoe daigremontiana

Author:
Rascher, U.,   et al.   ; Bohn, A.; Geist, A.; Luttge, U.;     Show all 4 Authors
Source:
Plant, cell and environment 2001 v.24 no.8 pp. 811-820
ISSN:
0140-7791
Subject:
carbon dioxide; stomatal conductance; oscillation; gas exchange; Kalanchoe daigremontiana; Crassulacean acid metabolism; light intensity; diurnal variation; stomata; circadian rhythm; water vapor; leaf conductance
Abstract:
... Time series of net CO2 exchange (J(CO2)) and leaf conductivity for water vapour (g(H2O)) were measured and subsequently analysed mathematically in the Crassulacean acid metabolism (CAM) plant Kalanchoe daigremontiana (Hamet et Perrier de la Bathie) under constant environmental conditions and under imposed external rhythms of lower and higher light intensity. The time series were analysed by Fourie ...
DOI:
10.1046/j.0016-8025.2001.00732.x

20. Spatiotemporal variation of metabolism in a plant circadian rhythm: the biological clock as an assembly of coupled individual oscillators

Author:
Rascher, U.,   et al.   ; Hutt, M.T.; Siebke, K.; Osmond, B.; Beck, F.; Luttge, U.;     Show all 6 Authors
Source:
Proceedings of the National Academy of Sciences of the United States of America 2001 v.98 no.20 pp. 11801-11805
ISSN:
0027-8424
Subject:
temporal variation; carbon dioxide; fluorescence; Kalanchoe daigremontiana; gas exchange; Crassulacean acid metabolism; spatial variation; circadian rhythm; chlorophyll
Abstract:
... The complex dynamic properties of biological timing in organisms remain a central enigma in biology despite the increasingly precise genetic characterization of oscillating units and their components. Although attempts to obtain the time constants from oscillations of gene activity and biochemical units have led to substantial progress, we are still far from a full molecular understanding of endog ...
DOI:
10.1073/pnas.191169598
PubMed:
11573013
PubMed Central:
PMC58811