Analysis of Chlorophyll Fluorescence: A Reliable Technique in Determination of Stress on Plants

2018 ◽  
pp. 63-88 ◽  
Author(s):  
M. K. Adak
Keyword(s):  
Chlorophyll Fluorescence ◽  
Reliable Technique

Comparison of Chlorophyll Fluorescence and Fresh Weight as Herbicide Bioassay Techniques

Weed Science ◽  
1985 ◽  
Vol 33 (1) ◽  
pp. 29-33 ◽  
Author(s):  
David R. Shaw ◽  
Thomas F. Peeper ◽  
D. L. Nofziger
Keyword(s):  
Chlorophyll Fluorescence ◽  
Avena Sativa ◽  
Inflection Point ◽  
Plant Size ◽  
Variable Fluorescence ◽  
Fresh Weight ◽  
Reliable Technique ◽  
Treated Soil ◽  
Fluorescence Maximum

The sensitivities of chlorophyll fluorescence and fresh weight as bioassay techniques for the determination of metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5 (4H)-one], diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], and atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] concentrations in soil were compared. The ratio of the initial inflection point (I) to the variable fluorescence maximum (P) of intact oat (Avena sativaL. ‘Chilocco’) leaves was determined for plants seeded directly into herbicide-treated soil and for those transplanted into treated soil after 14 days of growth in nutrient solution. Using the chlorophyll fluorescence of transplanted oats bioassay, 0-, 0.13-, 0.25-, and 0.50-ppm concentrations could be distinguished from one another within 8 h for metribuzin, within 24 h for diuron, and within 48 h for atrazine. These distinctions between rates could not be made 17 days after seeding into treated soil when using fresh weight as the bioassay indicator. Chlorophyll fluorescence of oats seeded directly into treated soil was also a reliable technique, but required much more time to attain sufficient plant size for convenient chlorophyll fluorescence determinations.

scholarly journals Determination of the influence of herbicides on dicotyledons plant transpiration using the sap flow method

2014 ◽  
Vol 60 (No. 12) ◽  
pp. 562-568 ◽  
Author(s):  
V. Brant ◽  
J. Pivec ◽  
K. Hamouzová ◽  
P. Zábranský ◽  
J. Satrapová ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Transpiration Rate ◽  
Sap Flow ◽  
Herbicide Application ◽  
Plant Transpiration ◽  
Flow Method ◽  
Infrared Gas Analyser ◽  
The Impact ◽  
Q Values

Physiological parameters are sensitive and provide information on the toxicity of herbicides in plants. The impact of herbicide application on plant transpiration was evaluated by the sap flow method during 2009&ndash;2011. The aim of this work was to verify the sap flow method for determining the effect of herbicides on the basis of continuous measurements of the transpiration flow. Helianthus annuus was used as a model plant species. The two different herbicides tested in this study differed by the effect of active ingredients bromoxynil and clopyralid. The water flow was measured using sap flow meter T4.2. The impact of herbicides was assessed by comparing measured transpiration rate (Q) after herbicide application with an extrapolation of transpiration rate of plants before herbicide treatment (Q<sub>calc</sub>). After treatment with bromoxynil the Q values decreased significantly compared to Q<sub>calc</sub>. For plants treated by clopyralid, the decline of actual transpiration (Q) compared with the modelled one (Q<sub>calc</sub>) was less substantial and the plants continued to transpire after the treatment. The effect of herbicides was also verified using infrared gas analyser and chlorophyll fluorescence meter.

Determination of Diphenylhydantoin in Human Serum by Spin Immunoassay

1975 ◽  
Vol 21 (2) ◽  
pp. 221-226 ◽  
Author(s):  
Mark R Montgomery ◽  
Jordan L Holtzman ◽  
Richard K Leute ◽  
John S Dewees ◽  
Gunner Bolz
Keyword(s):  
Human Serum ◽  
Cross Reactivity ◽  
Precise Estimate ◽  
Reliable Technique ◽  
Precise Method

Abstract A spin immunoassay for diphenylhydantoin is reported, which appears to give an accurate and precise estimate of serum diphenylhydantoin concentrations, as judged by the disappearance of [14C] diphenylhydantoin from the serum of a rabbIt. The assay also appears to be a reliable technique for routine diphenylhydantoin determinations, as judged from our experience with 28 patients. Serum diphenylhydantoin concentrations in the range of 1.0-50.0 mg/liter are easily determined on a 50-µl sample. Except for primidone, no significant cross reactivity was observed with eight drugs that are commonly used in conjunction with diphenylhydantoin therapy. This fast, simple, and precise method therefore appears to be readily applicable to routine determination of diphenylhydantoin.

The Percentage of Migration as Indicator of Femoral Head Position

1988 ◽  
Vol 29 (3) ◽  
pp. 363-366 ◽  
Author(s):  
O. Eklöf ◽  
H. Ringertz ◽  
L. Samuelsson
Keyword(s):  
Femoral Head ◽  
Head Position ◽  
Pediatric Age ◽  
Reliable Technique ◽  
Early Stages

In childhood subluxation of one or both hips may develop rather insidiously. For lack of generally accepted objective methods of assessment, ambiguous interpretations of findings in serial examinations are common. Many subluxations are overlooked during the early stages. In order to overcome such disadvantages, determination of the percentage of migration seems to be a reasonably easy and reliable technique facilitating evaluation of impending dislocation. This investigation was carried out in order to establish norms applicable to patients in the pediatric age interval. The 98th percentile of migration increases with age from 16 per cent in patients <4 years of age to 24 per cent in patients ≥12 years. Higher figures represent subluxation. If the migration exceeds 80 per cent a manifest luxation is present. A difference in migration between the two hips larger than 12 per cent indicates abnormality calling for clinical and radiologic follow-up.

scholarly journals Determination of human platelet antigen frequencies in the Dutch population by immunophenotyping and DNA (allele-specific restriction enzyme) analysis

Blood ◽  
1993 ◽  
Vol 81 (3) ◽  
pp. 835-840 ◽  
Author(s):  
S Simsek ◽  
NM Faber ◽  
PM Bleeker ◽  
AB Vlekke ◽  
E Huiskes ◽  
...  
Keyword(s):  
Internal Control ◽  
Human Platelet ◽  
Enzyme Analysis ◽  
Restriction Enzyme Analysis ◽  
Dutch Population ◽  
Reliable Technique ◽  
Platelet Antigen ◽  
Allele Specific ◽  
Specific Restriction

Abstract Platelets from 200 random Dutch blood donors were typed for the human platelet alloantigens HPA-1 to -5 recognized at present and for Naka. Naka is an epitope on glycoprotein IV, not expressed on the platelet of individuals with hereditary GP IV deficiency. Platelet immunofluorescence and monoclonal antibody-specific immobilization of platelet antigens (MAIPA) were applied for this purpose. The observed phenotype frequencies were 97.86% and 28.64% for HPA-1a and -1b, 100% and 13.15% for HPA-2a and -2b, 80.95% and 69.84% for HPA-3a and -3b, 100% and 0% for HPA-4a and -4b, 100% and 19.7% for HPA-5a and HPA-5b, respectively. Platelets from all donors reacted with the anti-Naka antibodies. To determine the gene frequencies for the HPA-1, HPA-2 and HPA-3 systems directly, DNA from 98 of these donors was isolated from peripheral blood mononuclear leucocytes and specific fragments were amplified by polymerase chain reaction (PCR). The fragments were analyzed using allele-specific restriction enzymes (ASRA). In all amplified PCR products an “internal control” for each assay, ie, a restriction site for the applied enzyme independent from the phenotype of the donor was present. In all donors tested, phenotypes, as determined by serological methods and genotypes, directly determined by the ASRA, were identical. Thus, the PCR-ASRA described in this report is a practical and reliable technique for the determination of alleles that code for platelet antigen allotypes, at least in the Dutch population.

Sign in / Sign up

Export Citation Format

Share Document