Hostname: page-component-76fb5796d-zzh7m Total loading time: 0 Render date: 2024-04-30T03:36:09.541Z Has data issue: false hasContentIssue false
  • English
  • Français

Influence of Ammonium Thiocyanate on Scorching and Control of Bracken (Pteridium aquilinum) by Amitrole

Published online by Cambridge University Press:  12 June 2017

G. T. Cook ,
N. H. Stephen  and
H. J. Duncan
G. T. Cook
Affiliation:
Agric. Chem. Dep., Univ. of Glasgow, Glasgow G12 8QQ, Scotland
N. H. Stephen
Affiliation:
Agric. Chem. Dep., Univ. of Glasgow, Glasgow G12 8QQ, Scotland
H. J. Duncan
Affiliation:
Agric. Chem. Dep., Univ. of Glasgow, Glasgow G12 8QQ, Scotland
Get access Rights & Permissions [Opens in a new window]

Abstract

The field performance of amitrole (3-amino-s-triazole) formulations containing a number of additives was tested on bracken [Pteridium aquilinum (L.) Kuhn var. aquilinum]. All formulations that did not contain thiocyanate produced severe foliar scorching within 72 h of spraying. The following season, control was relatively poor (63 to 77% reductions in frond density). The formulation of amitrole with sodium iodide produced particularly severe scorching followed by a nonsignificant reduction in frond density (2%) the following season. Formulations containing ammonium thiocyanate (molar ratios of 1:0.5, 1:0.75, 1:1, and 1:1.25 amitrole:ammonium thiocyanate) greatly reduced this foliar scorching, and control the following season was of the order of 94 to 97% in all cases. Translocation was proposed as being the limiting factor in control, ammonium thiocyanate increasing translocation by preventing scorching and hence decreasing decomposition in the foliage. To investigate scorching further, a bioassay, which consisted of floating bracken leaflets on amitrole solutions, was developed. The commercial 1:1 molar ratio of amitrole:ammonium thiocyanate may not be optimum for all conditions. Other additives were tested and cyanide and hexacyanoferrate (II) were found to be very active scorch inhibitors.

Keywords

Translocationfree radical inhibitorscyanidehexancyanoferrate (II)
Type
Research Article
Information
Weed Science , Volume 29 , Issue 2 , March 1981 , pp. 196 - 200
Copyright
Copyright © 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. Babiker, A. G. T. and Duncan, H. J. 1975. Penetration of bracken fronds by amitrole as influenced by pre-spraying conditions, surfactants and other additives. Weed Res. 15:123–127.CrossRefGoogle Scholar
2. Carter, M. C. 1975. Amitrole. Pages 377–398 in Kearney, P. C. and Kaufman, D. D., eds. Herbicides-Chemistry, Degradation and Mode of Action, 2nd ed., Vol. 1, Marcel Dekker, Inc., New York.Google Scholar
3. Castelfranco, P. and Brown, M. S. 1963. A hypothesis of amitrole action based on its behavior toward free radical generating systems. Weeds 11:116–124.CrossRefGoogle Scholar
4. Cook, G. T., Babiker, A. G. T., and Duncan, H. J. 1977. Penetration of bean leaves by aminotriazole as influenced by adjuvants and humidity. Pestic. Sci. 8:137–146.CrossRefGoogle Scholar
5. Cook, G. T. and Duncan, H. J. 1979. Mode of action of thiocyanates and iodides in aminotriazole formulations. Pestic. Sci. 10:281–290.Google Scholar
6. Crafts, A. S. 1961. The Chemistry and Mode of Action of Herbicides. Interscience Publishers, New York and London. 269 pp.Google Scholar
7. Donnalley, W. F. and Ries, S. K. 1964. Amitrole translocation in Agropyron repens increased by the addition of ammonium thiocyanate. Science 145:497–498.Google Scholar
8. Erskine, D. S. C. 1968. Experimental work in the chemical control of bracken 1958–1968. Proc. Br. Weed Contr. Conf. 9:488–492.Google Scholar
9. Forde, B. J. 1966. Translocation patterns of amitrole and ammonium thiocyanate in quackgrass. Weeds 14:178–179.CrossRefGoogle Scholar
10. Massini, P. 1963. Aminotriazolylalanine:a metabolic product of aminotriazole from plants. Acta Bot. Neerl. 12:64–72.CrossRefGoogle Scholar
11. Mynett, A. and Wain, R. L. 1971. Selective herbicidal activity of iodide in relation to iodide accumulation and foliar peroxidase activity. Pestic. Sci. 2:238–242.Google Scholar
12. Mynett, A. and Wain, R. L. 1973. Herbicidal activity of iodide: effect on chlorophyll content and photosynthesis in dwarf bean Phaseolus vulgaris . Weed Res. 13:101–109.Google Scholar
13. Racusen, D. 1958. The metabolism and translocation of 3-aminotriazole in plants. Arch. Biochem. Biophys. 74:106–113.Google Scholar
14. Soper, D. 1972. Review of bracken control experiments with asulam. Proc. Br. Weed Contr. Conf. 11:23–31.Google Scholar
15. Treinin, A. and Hayon, E. 1976. Quenching of triplet states by inorganic ions. Energy transfer and charge transfer mechanism. J. Am. Chem. Soc. 98:3884–3891.Google Scholar
16. Wain, R. L., Balayannis, P. G., Taylor, H. F., and Zaki, M. A. 1966. Selective herbicidal activity of iodides. Nature (London) 209:98.CrossRefGoogle ScholarPubMed