Abstract:
:A new device for the measurement of complete laser induced fluorescence emission spectra (maxima near 690 and 735 nm) of leaves during the induction of the chlorophyll fluorescence is described. In this the excitation light (cw He/Ne laser, 632.8 nm) is switched on by a fast electro-mechanical shutter which provides an opening time of 1 ms. The emitted fluorescence is imaged onto the entrance slit of a multichannel spectrograph through a red cut-off filter (greater than 645 nm). A charge coupled device (CCD) sensor with 2048 elements simultaneously detects the complete chlorophyll fluorescence emission spectrum in the 650-800 nm wavelength range. Scanning is accomplished electronically and the integration time for a complete fluorescence emission spectrum can be selected from 10 ms up to 260 ms. Shutter, detector system and data acquisition are controlled by an IBM-PC/AT compatible computer. A maximum of 32 spectra can be measured at selected times during the fluorescence induction kinetics with the shortest time resolution of 10 ms. The instrument permits the determination of various fluorescence parameters: a) the rise-time of the fluorescence to the maximum level fm, b) the changes in the shape of the fluorescence emission spectra during the induction kinetics, c) the induction kinetics in the fluorescence ratio F690/F735 as well as d) the fluorescence decrease ratio Rfd at any wavelength between 650 to 800 nm. These fluorescence parameters provide information about the functioning of photosynthesis. The ratio F690/F735 allows the non-destructive determination of the chlorophyll content of leaves. The application of this instrument in ecophysiological research and stress physiology of plants is outlined.
journal_name
Radiat Environ Biophysjournal_title
Radiation and environmental biophysicsauthors
Szabó K,Lichtenthaler HK,Kocsányi L,Richter Pdoi
10.1007/BF01211213keywords:
subject
Has Abstractpub_date
1992-01-01 00:00:00pages
153-60issue
2eissn
0301-634Xissn
1432-2099journal_volume
31pub_type
杂志文章abstract::With a model system of pBR322 plasmid DNA solution in vitro, the dose effects of radiation-induced single- and double-strand breaks (SSB and DSB) were measured and DSB was distinguished into alpha- and beta-types. Under the condition of low scavenging capacity existing in the irradiated DNA solution, SSB and alpha DSB...
journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/s004110000054
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/s00411-015-0623-4
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pub_type: 杂志文章
doi:10.1007/s00411-006-0058-z
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01210525
更新日期:1990-01-01 00:00:00
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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更新日期:1978-08-10 00:00:00
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01323421
更新日期:1975-12-04 00:00:00
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pub_type: 杂志文章
doi:10.1007/s00411-002-0153-8
更新日期:2002-06-01 00:00:00
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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更新日期:1994-01-01 00:00:00
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章,评审
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01324267
更新日期:1980-01-01 00:00:00
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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更新日期:1986-01-01 00:00:00
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journal_title:Radiation and environmental biophysics
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01323619
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
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更新日期:2017-03-01 00:00:00
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/s004110050088
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章,meta分析
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更新日期:2007-11-01 00:00:00
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01324271
更新日期:1980-01-01 00:00:00
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journal_title:Radiation and environmental biophysics
pub_type: 杂志文章
doi:10.1007/BF01213732
更新日期:1984-01-01 00:00:00