Hostname: page-component-77c89778f8-m8s7h Total loading time: 0 Render date: 2024-07-16T12:23:52.576Z Has data issue: false hasContentIssue false
  • English
  • Français

A Method of Comparing Herbicides and Assessing Herbicide Mixtures at the Screening Level

Published online by Cambridge University Press:  12 June 2017

Donald P. Gowing
Donald P. Gowing*
Affiliation:
Pineapple Research Institute of Hawaii
Get access

Extract

A very useful technique in toxicological investigation is probit analysis. This method, which was developed by Bliss and other workers (notably Gaddum and Finney, but see reference 4, pp. 42–46) consists of plotting the log concentration of a toxicant against the percentage response on a probability scale, and fitting a weighted regression line to the data. Although the technique has found wide application in pharmacology, entomology, and plant pathology, it has been almost ignored by workers in herbicide research. It is the purpose of this paper to demonstrate that the concepts of probit analysis are applicable to herbicide research, and that the mere plotting of data on logarithmic probability paper may permit a very fruitful interpretation of experimental results. The technique is recommended at the screening level, for its results are very useful in the construction of field tests. It is in no sense a substitute for the carefully designed and executed field test, or for the analysis of test results by other statistical techniques.

Type
Research Article
Information
Weeds , Volume 7 , Issue 1 , January 1959 , pp. 66 - 76
Copyright
Copyright © 1959 Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Blackman, G. E. Studies in the principles of phytotoxicity. I. The assessment of relative toxicity. J. Exptl. Bot. 3:1–27. 1952.Google Scholar
2. Bliss, C. I. The calculation of the dosage-mortality curve. Ann. Appl. Biol. 22:134–167. 1935.Google Scholar
3. Bliss, C. I. The toxicity of poisons applied jointly. Ann. Appl. Biol. 26:585–615. 1939.Google Scholar
4. Finney, D. J. Probit Analysis. 2nd ed., pp. 1–318. Cambridge Univ. Press. 1952.Google Scholar
5. Horsfall, J. G. Principles of Fungicidal Action. pp. 1–279. Chronica Botanica, Waltham, Mass. 1956.Google Scholar
6. Litchfield, J. T. Jr., and Wilcoxon, F. A simplified method of evaluating dose-effect experiments. Jour. of Pharmacology and Exptl. Therapeutics 96:99–113. 1949.Google Scholar
7. McCallan, S. E. A. Mechanisms of toxicity with special reference to fungicides. Proc. Second Internat. Plant Protection Conference. pp. 77–95. Buttersworths Sci. Publ., London. 1956.Google Scholar
8. Sampford, M. R. Studies in the principles of phytotoxicity. II. Experimental designs and techniques of statistical analysis for the assessment of toxicity. J. Exptl. Bot. 3:28–46. 1952.Google Scholar
9. Simon, E. W., Roberts, H. A., and Blackman, G. E. Studies in the principles of phytotoxicity. III. The pH factor and the toxicity of 3,5–dinitro–o–cresol, a weak acid. J. Exptl. Bot. 3:99–109. 1952.Google Scholar
10. Simon, E. W., and Blackman, G. E. Studies in the principles of phytotoxicity. IV. The effects of degree of nitration on the toxicity of phenol and other substituted benzenes. J. Exptl. Bot. 4:235–250. 1953.Google Scholar
11. Turner, N., and Bliss, C. I. Tests of synergism between nicotine and the pyrethrins. Ann. Appl. Biol. 40:79–90. 1953.Google Scholar
12. Wilcoxon, F., and McCallan, S. E. A. Theoretical principles underlying laboratory toxicity tests of fungicides. Contr. Boyce Thompson Inst. 10:329–338. 1939.Google Scholar