Journal of Chemical Ecology

, Volume 18, Issue 1, pp 1–11 | Cite as

Phytotoxicity of sorgoleone found in grain Sorghum root exudates

  • Frank A. Einhellig
  • Itamar F. Souza


Root exudates ofSorghum bicolor consist primarily of a dihydroquinone that is quickly oxidized to ap-benzoquinone named sorgoleone. The aim of this investigation was to determine the potential activity of sorgoleone as an inhibitor of weed growth. Bioassays showed 125μM sorgoleone reduced radicle elongation ofEragrostis tef. In liquid culture, 50-μM sorgoleone treatments stunted the growth ofLemna minor. Over a 10-day treatment period, 10μM sorgoleone in the nutrient medium reduced the growth of all weed seedlings tested:Abutilon theophrasti, Datura stramonium, Amaranthus retroflexus, Setaria viridis, Digitaria sanguinalis, andEchinochloa crusgalli. These data show sorgoleone has biological activity at extremely low concentrations, suggesting a strong contribution toSorghum allelopathy.

Key words

Sorgoleone phytotoxin allelochemical allelopathy root exudate Sorghum bicolor Sorghums weed inhibition 


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  1. Abdul-Wahab, A.S., andRice, E.L. 1967. Plant inhibition by Johnson grass and its possible significance in old-field succession.Bull. Torrey Bot. Club. 94:486–497.Google Scholar
  2. Alsaadawi, I.S., Al-Uqaili, J.K., Alrubeaa, A.J., andAl-Hadithy, S.M. 1986. Allelopathic suppression of weed and nitrification by selected cultivars ofSorghum bicolor (L.) Moench.J. Chem. Ecol. 12:209–219.Google Scholar
  3. Boe, A., Sommerfeldt, J., Wynia, R., andThiex, N. 1986. A preliminary evaluation of the forage potential of teff.Proc. S. Dak. Acad. Sci. 65:75–82.Google Scholar
  4. Breazeale, J.F. 1924. The injurious after-effects of sorghum.J. Am. Soc. Agron. 16:689–700.Google Scholar
  5. Chang, M., Netzly, D.H., Butler, L.G., andLynn, D.G. 1986. Chemical regulation of distance: Characterization of the first natural host germination stimulant forStriga asiatica.J. Am. Chem. Soc. 108:7858–7860.Google Scholar
  6. Cleland, C.F., andBriggs, W.R. 1967. Flowering response of the long-day plantLemna gibba G3.Plant Physiol. 42:1553–1561.Google Scholar
  7. Einhellig, F.A. 1986. Mechanisms and modes of action of allelochemicals, pp. 171–188,in A.R. Putnam and C.S. Tang (eds.). The Science of Allelopathy. John Wiley & Sons, New York.Google Scholar
  8. Einhellig, F.A. 1989. Interactive effects of allelochemicals and environmental stress, pp. 101–118,in C.H. Chou and G.R. Waller (eds.). Phytochemical Ecology: Allelochemicals, Mycotoxins and Insect Pheromones and Allomones. Institute of Botany, Academia Sinica Mongraph Series No. 9. Taipei, Taiwan.Google Scholar
  9. Einhellig, F.A., andRasmussen, J.A. 1979. Effects of three phenolic acids on chlorophyll content and growth of soybean and grain sorghum seedlings.J. Chem. Ecol. 5:815–824.Google Scholar
  10. Einhellig, F.A., andRasmussen, J.A. 1989. Prior cropping with grain sorghum inhibits weeds.J. Chem. Ecol. 15:951–960.Google Scholar
  11. Einhellig, F.A., Rice, E.L., Risser, P.G., andWender, S.H. 1970. Effects of scopoletin on growth, CO2 exchange rates, and concentration of scopoletin, scopolin, and chlorogenic acids in tobacco, sunflower, and pigweed.Bull. Torrey Bot. Club 97:22–33.Google Scholar
  12. Einhellig, F.A., Leather, G.R., andHobbs, L.L. 1985. Use ofLemna minor L. as a bioassay in allelopathy.J. Chem. Ecol. 11:65–72.Google Scholar
  13. Fate, G., Chang, M., andLynn, D.G. 1990. Control of germination inStriga asiatica: Chemistry of spatial definition.Plant Physiol. 93:201–207.Google Scholar
  14. Forney, D.R., Foy, C.L., andWolf, D.D. 1985. Weed suppression in no-till alfalfa (Medicago sativa) by prior cropping of summer-annual forage grasses.Weed Sci. 33:490–497.Google Scholar
  15. Guenzi, W.D., andMcCalla, T.M. 1966. Phenolic acids in oats, wheat, sorghum and corn residues and their phytotoxicity.Agron. J. 58:303–304.Google Scholar
  16. Guenzi, W.D., McCalla, T.M., andNordstadt, F.A. 1967. Presence and persistence of phytotoxic substances in wheat, oat, corn, and sorghum residues.Agron. J. 59:163–165.Google Scholar
  17. Haar, M.J. 1990. Allelopathic effects of several sesquiterpene lactones. MA thesis. University of South Dakota, Vermillion, South Dakota. 73 pp.Google Scholar
  18. Hoagland, D.R., andArnon, D.I. 1950. The water culture method for growing plants without soil. Calif. Agric. Exp. Stn. Circ. 347.Google Scholar
  19. Hussain, P., andGadoon, M.A. 1981. Allelopathic effects ofSorghum vulgare Pers.Oecologia 51:284–288.Google Scholar
  20. Lehle, F.R., andPutnam, A.R. 1983. Allelopathic potential of sorghum (Sorghum bicolor): Isolation of seed germination inhibitors.J. Chem. Ecol. 9:1223–1234.Google Scholar
  21. Martin, J.H., Couch, J.F., andBriese, R.R. 1938. Hydrocyanic acid content of different parts of the sorghum plant.J. Am. Soc. Agron. 30:725–734.Google Scholar
  22. Netzly, D.H., andButler, L.G. 1986. Roots ofSorghum exude hydrophobic droplets containing biologically active components.Crop Sci. 26:775–778.Google Scholar
  23. Netzly, D.H., Riopel, J.L., Ejeta, G., andButler, L.G. 1988. Germination stimulants of witchweed (Striga asiatica) from hydrophobic root exudate of Sorghum (Sorghum bicolor).Weed Sci. 36:441–446.Google Scholar
  24. Nicollier, G.F., Pope, D.F., andThompson, A.C. 1983. Biological activity of dhurrin and other compounds from Johnson grass (Sorghum halepense).J. Agric. Food Chem. 31:744–748.Google Scholar
  25. Panasiuk, O., Bills, D.D., andLeather, G.R. 1986. Allelopathic influence ofSorghum bicolor on weeds during germination and early development of seedlings.J. Chem. Ecol. 12:1533–1543.Google Scholar
  26. Purvis, C.E. 1990. Allelopathy: A new direction in weed control.Plant Prot. Q. 5:55–59.Google Scholar
  27. Putnam, A.R., andDefrank, J. 1983. Use of phytotoxic plant residues for selective weed control.Crop Prot. 2:173–181.Google Scholar
  28. Putnam, A.R., DeFrank, J., andBarnes, J.P. 1983. Exploitation of allelopathy for weed control in annual and perennial cropping systems.J. Chem. Ecol. 8:1001–1010.Google Scholar
  29. Ramirez-Toro, G.I., Leather, G.R., andEinhellig, F.A. 1988. Effects of three phenolic compounds onLemna gibba G3.J. Chem. Ecol. 14:845–853.Google Scholar
  30. Rice, E.L. 1984. Allelopathy. Academic Press, Orlando, Florida, 422 pp.Google Scholar
  31. Rietveld, W.J. 1983. Allelopathic effects of juglone on germination and growth of several herbaceous and woody species.J. Chem. Ecol. 9:295–308.Google Scholar
  32. Scholes, K.A. 1987. Effects of six classes of allelochemicals on growth, photosynthesis, and chlorophyll content inLemna minor L. MA thesis. University of South Dakota, Vermillion, South Dakota. 81 pp.Google Scholar
  33. Weston, L.A., Harmon, R., andMueller, S. 1989. Allelopathic potential of sorghum-sudangrass hybrid (sudex).J. Chem. Ecol. 15:1855–1865.Google Scholar
  34. Wintermans, J.F.G.M., andDeMots, A. 1965. Spectrophotometry characteristics of chlorophylls a and b and their pheophytins in ethanol.Biochim. Biophys. Acta 109:448–453.Google Scholar

Copyright information

© Plenum Publishing Corporation 1992

Authors and Affiliations

  • Frank A. Einhellig
    • 1
  • Itamar F. Souza
    • 2
  1. 1.Department of Biology University of South DakotaVermillion
  2. 2.Minas Gerais Livestock and Agriculture Research Institute (EPAMIG)Lavras, MGBrazil

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