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1872. Multi-colour fluorescence imaging of photosynthetic activity and plant stress

Creator:
Lichtenthaler, H. K.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
fluorescence, Kautsky effect, chlorophyll fluorescence decrease ratio, chlorophyll fluorescence induction kinetics, fluorescence ratio images, 2, and 581
Language:
Multiple languages
Description:
a1_Imaging the four fluorescence bands of leaves, the red (F690) and far-red (F740) chlorophyll (Chl) fluorescence as well as the blue (F440) and green (F520) fluorescence of leaves and the corresponding fluorescence ratios is a fast and excellent nondestructive technique to detect the photosynthetic activity and capacity of leaves, of gradients over the leaf area as well as the effect of various strain and stress parameters on plants. This review primarily deals with the first and pioneering multi-colour fluorescence imaging results obtained since the mid-1990s in a cooperation with French colleagues in Strasbourg and in my laboratory in Karlsruhe. Together we introduced not only the joint imaging of the red and far-red Chl fluorescence but also of the blue and green fluorescence of leaves. The two instrumental setups composed for this purpose were (1) the Karlsruhe-Strasbourg UV-Laser Fluorescence Imaging System (Laser-FIS) and (2) the Karlsruhe Flash-Light Fluorescence Imaging System (FL-FIS). Essential results obtained with these instruments are summarized as well as the basic principles and characteristics of multi-colour fluorescence imaging. The great advantage of fluorescence imaging is that the fluorescence yield in the four fluorescence bands is sensed of several thousand up to 200,000 pixels per leaf area in one image. The multi-colour FIS technique allows to sense many physiological parameters and stress effects in plants at an early stage before a damage of leaves is visually detectable. Various examples of plant stress detection by the multi-colour FIS technique are given. Via imaging the Chl fluorescence ratio F690/F740 it is even possible to determine the Chl content of leaves. The FIS technique also allows to follow the successive uptake of diuron and loss of photosynthetic function and to screen the ripening of apples during storage., a2_Particularly meaningful and of high statistical relevance are the fluorescence ratio images red/far-red (F690/F740), blue/red (F440/F690), and blue/green (F440/F520) as well as images of the fluorescence decrease ratio RFd, which is an indicator of the net CO2 assimilation rates of leaves., H. K. Lichtenthaler., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1873. Multi-objective environment chamber system for studying plant responses to climate change

Creator:
Zhou, X., Ge, Z. M., Kellomäki, S., Wang, K. Y., Peltola, H., Martikainen, P. J., Lemettinen, M., Hassinen, A., and Ikonen, R.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, autocontrolled environment chamber, boreal grass, chamber effect, climate change, 2, and 58
Language:
Multiple languages
Description:
This paper describes the technical information and performance of a new multi-objective chamber system enabling the control of environmental variables (e.g., temperature, CO2, air humidity, wind speed, and UV-B radiation) for understanding plant responses to climate change. Over a whole growing season, four different climate scenarios were evenly programmed into the system’s 16 chambers as ambient environment (AMB), elevated temperature (ET), elevated CO2 concentration (EC) and elevated temperature and CO2 concentration (ETC). Simultaneously, the chamber effects were assessed regarding the physiological responses and growth of a boreal perennial grass (reed canary grass, Phalaris arundinacea L.). During the growing season, the chamber system provided a wide variety of climatic conditions for air temperature (T a), relative humidity (RH) and CO2 concentration (C a) in the AMB chambers following outside conditions. The target temperature (+3.5°C) was achieved to a good degree in the ET and ETC chambers, being on average 3.3°C and 3.7°C higher than ambient conditions, respectively. The target concentration of CO2 (700 ppm) was also well achieved in the EC and ETC chambers, being on average 704 ppm and 703 ppm, respectively. The stable airflow condition inside all of the chambers provided a homogeneous distribution of gases and temperature. The decreases in RH and increases in vapour pressure deficit (VPD) in the elevated temperature chambers were also maintained at a low level. Chamber effects were observed, with some physiological and growth parameters of plants being significantly lower in the AMB chambers, compared to outside conditions. The plant growth was negatively affected by the reduced radiation inside the chambers., X. Zhou ... [et al.]., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1874. Multi-phasic kinetics of P700+ dark re-reduction in Nicotiana tabacum

Creator:
Jin, Ming-Xian, Yao, Zheng-Ju, and Mi, Hualing
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
far-red radiation, photosystem 1, and tobacco
Language:
Multiple languages
Description:
Reduction kinetics of P700+ after far-red radiation (FR)-induced oxidation in intact tobacco leaves was examined by analysing the post-irradiation relaxation of 810-830 nm absorbance difference. The reduction curve could be de-convoluted distinctively into two or three exponential decaying components, depending on the FR irradiance, the treating and measuring temperatures, and the extent of dark adaptation. The multi-phasic kinetics of P700+ re-reduction upon the turning off of FR irradiation is related to the heterogeneity of electron transport around photosystem 1 in thylakoid membranes. and Ming-Xian Jin, Zheng-Ju Yao, Hualing Mi.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1875. Multicolour fluorescence imaging of sugar beet leaves with different nitrogen status by flash lamp UV-excitation

Creator:
Langsdorf, G., Buschmann, C., Sowinska, M., Babani, F., Mokry, M., Timmermann, F., and Lichtenthaler, H. K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Beta vulgaris L., blue-green fluorescence, chlorophyll fluorescence, fluorescence ratios, nitrogen nutrition, photosynthetic activity, protein, sugars, and yield
Language:
Multiple languages
Description:
Fluorescence images of leaves of sugar beet plants (Beta vulgaris L. cv. Patricia) grown on an experimental field with different fertilisation doses of nitrogen [0, 3, 6, 9, 12, 15 g(N) m-2] were taken, applying a new multicolour flash-lamp fluorescence imaging system (FL-FIS). Fluorescence was excited by the UV-range (280-400 nm, λmax = 340 nm) of a pulsed Xenon lamp. The images were acquired successively in the four fluorescence bands of leaves near 440, 520, 690, and 740 nm (F440, F520, F690, F740) by means of a CCD-camera. Parallel measurements were performed to characterise the physiological state of the leaves (nitrogen content, invert-sugars, chlorophylls and carotenoids as well as chlorophyll fluorescence induction kinetics and beet yield). The fluorescence images indicated a differential local patchiness across the leaf blade for the four fluorescence bands. The blue (F440) and green fluorescence (F520) were high in the leaf veins, whereas the red (F690) and far-red (F740) chlorophyll (Chl) fluorescences were more pronounced in the intercostal leaf areas. Sugar beet plants with high N supply could be distinguished from beet plants with low N supply by lower values of F440/F690 and F440/F740. Both the blue-green fluorescence and the Chl fluorescence rose at a higher N application. This increase was more pronounced for the Chl fluorescence than for the blue-green one. The results demonstrate that fluorescence ratio imaging of leaves can be applied for a non-destructive monitoring of differences in nitrogen supply. The FL-FIS is a valuable diagnostic tool for screening site-specific differences in N-availability which is required for precision farming. and G. Langsdorf ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1879. Mutation mechanism of chlorophyll-less barley mutant NYB

Creator:
Liu, Z.-L., Yuan, S., Liu, W.-J., Du, J.-B., Tian, W.-J., Luo, M.-H., and Lin, H.-H.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll, fluorescence emission spectra, light-harvesting complex 2, Nanchong yellow barley (NYB), nucleotide sequences, photosystem 2, proteins, and protochlorophyllide oxidoreductase (POR)
Language:
Multiple languages
Description:
NYB is chlorophyll-less barley mutant, which is controlled by a recessive nuclear gene. The mutation mechanism is revealed. The activities of enzymes transforming 5-aminolevulinic acid into protochlorophyllide were the same in both NYB and the wild type (WT), but the activity of the protochlorophyllide oxidoreductase (POR) in WT was much higher than that of NYB. Most of the photosystem 2 apoproteins were present in both WT and NYB, suggesting that the capability of protein synthesis was probably fully preserved in the mutant. Thus chlorophyll (Chl) biosynthesis in NYB was hampered at conversion form protochlorophyllide (Pchlide) into chlorophyllide. The open reading frame of porB gene in NYB was inserted with a 95 bp fragment, which included a stop codon. The NYB mutant is a very useful material for studies of Chl biosynthesis, chloroplast signalling, and structure of light-harvesting POR-Pchlide complex (LHPP). and Z.-L. Liu ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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