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Interactions Between Soybean (Glycine max) Cultivars and Selected Weeds

  • David W. Monks (a1) and Lawrence R. Oliver (a1)


Competition of weeds was characterized by determining the distance down the soybean row that a weed affects soybean biomass and yield. Field studies were conducted for 2 yr to compare competitive effects of common cocklebur, johnsongrass, Palmer amaranth, sicklepod, and tall morningglory on ‘Forrest’ and ‘Centennial’ soybeans. The weeds did not significantly reduce soybean biomass for 6 weeks after emergence. Palmer amaranth, common cocklebur, and tall morningglory had the greatest biomass by 6 weeks after emergence. However, only competition from common cocklebur and Palmer amaranth measurably reduced soybean biomass during the growing season. Biomass of Forrest and Centennial soybeans was reduced when these cultivars were growing within 12.5 and 50 cm of common cocklebur, respectively. Johnsongrass, sicklepod, and tall morningglory grew more slowly than the other weeds and had no measurable competitive effects on soybean biomass. Soybean competition reduced biomass of all weeds 90 to 97%. Soybean cultivar influenced the level and duration of competitiveness depending on the weed species present. Biomass of both soybean cultivars was reduced when they were growing within 50 cm of Palmer amaranth. Soybean seed yield was reduced when soybeans were growing within 25 cm of common cocklebur and Palmer amaranth and also when they were growing within 12.5 cm of tall morningglory. Sicklepod had no effect on soybean seed yield.



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1. Barrentine, W. L. and Oliver, L. R. 1977. Competition, threshold levels, and control of cocklebur in soybeans. Miss. Agric. Exp. Stn. Bull. 83:127.
2. Brown, D. A. and Scott, H. D. 1984. Dependence of crop growth and yield on root development and activity. Pages 101136 in Soil Sci. Soc. Am., Crop Sci. Soc. Am., and Am. Soc. Agron., ed. Roots, Nutrient, and Water Influx, and Plant Growth. Madison, WI.
3. Davis, R. G., Weise, A. F., and Pafford, J. L. 1965. Root moisture extraction profiles of various weeds. Weeds 13:98100.
4. Dawson, J. H. 1965. Competition between irrigated sugarbeets and annual weeds. Weeds 13:245249.
5. Donald, C. M. 1958. The interaction of competition for light and nutrients. Aust. J. Agric. Res. 9:421435.
6. Fehr, W. R., Caviness, C. E., Burwood, D. T., and Pennington, J. S. 1971. Stage of development description for soybean [Glycine max (L.) Merrill]. Crop Sci. 11:929931.
7. Fischer, R. A. and Miles, R. E. 1973. The role of spatial pattern in the competition between crop plants and weeds. A theoretical analysis. Math. Biosci. 18:335350.
8. Grime, J. P. 1979. Plant Strategies and Vegetation Processes. John Wiley and Sons, New York. 222 pp.
9. Gunsolus, J. L. and Coble, H. D. 1985. Interference on weed and soybean growth and development. Proc. South. Weed Sci. Soc. 38:82.
10. Harper, J. L. 1977. Population Biology of Plants. Academic Press, New York. 892 pp.
11. Hinson, K. and Hanson, W. D. 1962. Competition studies in soybeans. Crop Sci. 2:117123.
12. McWhorter, C. G. and Hartwig, E. E. 1972. Competition of johnsongrass and cocklebur with six soybean varieties. Weed Sci. 20:5659.
13. Oliver, L. R., Frans, R. E., and Talbert, R. E. 1976. Field competition between tall morningglory and soybean. I. Growth analysis. Weed Sci. 24:482488.
14. Radosevich, S. R. and Holt, J. S. 1984. Weed Ecology Implications for Vegetation Management. John Wiley and Sons, New York. 265 pp.


Interactions Between Soybean (Glycine max) Cultivars and Selected Weeds

  • David W. Monks (a1) and Lawrence R. Oliver (a1)


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