Mechanism of Action of Fatty Alcohol Ethoxylate on Foliar Penetration of Dimethomorph into Cucumber

Fatty Alcohol Ethoxylate에 의해 유도되는 Dimethomorph의 오이 엽면 침투 기작

  • Yu, Ju-Hyun (Chemical Biotechnology Research Center, Korea Research Institute of Chemical Technology)
  • 유주현 (한국화학연구원 바이오정밀화학연구센터)
  • Published : 2008.06.30


The foliar uptake of dimethomorph into cucumber was assessed by spray application of aqueous dimethomorph solution containing fatty alcohol ethoxylate (FAE) or fatty acid alkyl ester as activator adjuvants. Afterward, the possible mechanism of action of FAE on foliar penetration of active ingredient was suggested by speculating on the effect of lipophile and hydrophile of FAEs. The amount of absorbed dimethomorph induced by polyoxyethylene mono-9-octadecenyl ether (6 moles ethylene oxide, $C_{18=9}E_6$) was linearly related to the concentrations of surfactant as well as dimethomorph in spray solution, suggesting that it is simply a diffusion phenomenon of the solute molecule through a cuticular membrane from leaf surface. Octadecanol attached to FAE was most effective lipophile on the leaf penetration of dimethomorph. And, the more ethylene oxide had the polyoxyethylene chain of FAE up to 20 moles, the higher the uptake rate was. Therefore, the role of lipophile of FAE on dimethomorph penetration to cucumber leaf, probably, is to modify the physico-chemical properties of cuticular membrane to be permeable to dimethomorph, and the polyoxyethylene chain having less than 20 moles ethylene oxide, which is moderately permeable to cuticular membrane by its molar volume, is to let the physically-modified cuticular membrane to be maintained for a longtime.


  1. Holloway, P. J. and D. Stock (1990) In Industrial Applications of Surfactants II (ed. D. R. Karsa), Special Publication No. 77, Royal Society of Chemistry, Cambridge, pp. 303-337
  2. Schonherr, J. (1993) Effects of alcohols, glycols and monodisperse ethoxylated alcohols on mobility of 2,4-D in isolated plant cuticles, Pestic. Sci., 39:213-223
  3. Stock, D., B. M. Edgerton, R. E. Gaskin and P. J. Holloway (1992) Surfactant-inhanced foliar uptake of some organic compounds: Interractions with two model polyoxyethylene alipatic alcohols. Pestic. Sci. 34:233-242
  4. Tomlin, C. D. S. (2000) In 'The Pesticide Manual' Twelfth Ed., British Crop Protection Council, Surrey, UK
  5. Kerler, F. and J. Schonherr (1988) Permeation of lipophilic chemicals across plant cuticles: Prediction from octanol/water partition coefficients and molecular volumes. Arch. Environ. Contam. Toxicol. 17:7-12
  6. Schonherr, J. and P. Baur (1994) Modelling penetration of plant cuticles by crop protection agents and effects of adjuvants on their rates of penetration. Pestic. Sci. 42:185-208
  7. Grayson, B. T., J. D. Webb, D. M. Batten and D. Edwards (1996a) Effect of adjuvants on the therapeutic activity of dimethomorph in controlling vine downy mildew. I. Survey of adjuvant types. Pestic. Sci. 46:199-206<199::AID-PS334>3.0.CO;2-N
  8. Grayson, B. T., S. L. Boyd and D. Walter (1996b) Effect of adjuvants on the therapeutic activity of dimethomorph in controlling vine downy mildew. II. Adjuvant mixtures, outdoor-hardened vines and one-pack formulations. Pestic. Sci. 46:207-213<207::AID-PS335>3.0.CO;2-B
  9. Stevens, P. J. G. and M. J. Bukovac (1987) Studies on octylphenoxy surfactants. Part 2: Effects on foliar uptake and translocation. Pestic. Sci. 20:37-52
  10. Stevens, P. J. G., E. A. Baker and N. H. Anderson (1988) Factors affecting the foliar absorption and redistribution of pesticides. 2. Physicochemical properties of the active ingredient and the role of surfactant, Pestic. Sci. 24:31-53
  11. Cho, K. Y., J. H. Yu, H. K. Lim, G. J. Choi and J. H. Kim (1999) Composition and Method for Measuring the Foliar Uptake of Agrochemicals. Patent KR-0314600
  12. Grayson, B. T., D. M. Batten and D. Walter (1996c) Adjuvant effects on the therapeutic control of potato late blight by dimethomorph wettable powder formulations. Pestic. Sci. 46:355-359<355::AID-PS364>3.0.CO;2-U
  13. Yu, J. H., G. J. Choi, H. K. Lim, J. H. Kim and K. Y. Cho (2001) Influence of surfactants on foliar uptake of dimethomorph into cucumber plant and fungicidal activity against cucumber downy mildew. J. Korean Soc. Agric. Chem. Biotechnol. 44:109-115
  14. Stock, D. and P. J. Holloway (1993) Possible mechanisms for surfactant-induced foliar uptake of agrochemicals. Pestic. Sci. 38:165-177
  15. Yu, J. H., K. Y. Cho and J. H. Kim (2000) Review of the study on the surfactant-induced foliar uptake of pesticide. The Korean journal of Pesticide Science 6:16-24
  16. Dehne, H-W (1997) Enhancement of the efficacy of fungicides, European patent application 0806141A1
  17. Baur, P., J., Sch?nherr and B. T. Grayson (1999) Polydisperse ethoxylated fatty alcohol surfactants as accelerators of cuticular penetration. 2. Separation of effects on driving force and mobility and reversibility of surfactant action, Pestic. Sci., 55, 831-842
  18. Bauer, H. and J. Sch?nherr (1992) Determination of mobilities of organic compounds in plant cuticles and correlation with molar volumes. Pestic. Sci. 35:1-11
  19. Schreiber, L., M. Riederer, and K. Schorn (1996) Mobilities of organic compounds in reconstituted cuticular wax of barley leaves: Effects of monodisperse alcohol ethoxylates on diffusion of pentachlorophenol and tetracosanoic acid. Pestic. Sci. 48:117-124<117::AID-PS448>3.0.CO;2-3
  20. Baker, E. A. (1980) Effect of cuticular components on foliar penetration. Pestic. Sci. 11:367-370