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Influence of emergence time and density on redroot pigweed (Amaranthus retroflexus)

Published online by Cambridge University Press:  12 June 2017

Stevan Z. Knezevic
Affiliation:
Department of Agronomy, Kansas State University, Manhattan, KS 66506-5501

Abstract

Field studies were conducted at two locations near Manhattan, KS, in 1994 and 1995 to determine the influence of density (0.5, 1, 2, 4, and 12 plants m−1 row) and time of emergence on redroot pigweed growth in monoculture or with sorghum. Redroot pigweed was seeded at sorghum planting and at the three- to four-leaf stage of sorghum in plots with sorghum or alone. When redroot pigweed grew with sorghum, dry matter and seed production were reduced with later times of emergence. In monoculture, there was no reduction in dry matter or seed number between the emergence dates studied. Redroot pigweed dry matter and seed production per plant were reduced as plant density increased for plants grown in monoculture. The same trend was observed for redroot pigweed grown with sorghum that did not emerge early relative to sorghum. Plants grown at low density exhibited more lateral growth than when grown at higher densities because of intraspecific competition.

Type
Weed Biology and Ecology
Copyright
Copyright © 1998 by the Weed Science Society of America 

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Footnotes

Current address; Haskell Agricultural Laboratory, University of Nebraska, Concord, NE 68728-2828

References

Literature Cited

Anonymous. 1992. Grain Sorghum Production Handbook. Cooperative Extension Service. Manhattan, KS: Kansas State University. 32 p.Google Scholar
Chikoye, D., Weise, S. F., and Swanton, C. J. 1995. Influence of common ragweed (Ambrosia artemisifolia) time of emergence and density on white bean (Phaseolus vulgaris) . Weed Sci. 43: 375380.CrossRefGoogle Scholar
Cousens, R. 1985. A simple model relating yield loss to weed density. Ann. Appl. Biol. 107: 239252.CrossRefGoogle Scholar
Cousens, R. 1988. Misinterpretation of results in weed research through inappropriate use of statistics. Weed Res. 28: 281289.CrossRefGoogle Scholar
Cousens, R. 1991. Aspects of the design and interpretation of competition (interference) experiments. Weed Technol. 5: 664673.CrossRefGoogle Scholar
Dieleman, A., Hamill, A. S., Weise, S. F., and Swanton, C. J. 1995. Empirical models of pigweed (Amaranthus spp.) interference in soybean (Glycine max) . Weed Res. 43: 612618.CrossRefGoogle Scholar
Gomez, A. K. and Gomez, A. A. 1984. Statistical Procedures for Agricultural Research. 2nd ed. International Rice Research Institute. New York: Wiley-Interscience, pp. 108116.Google Scholar
Harper, J. L., Lovell, P. H., and Moore, K. G. 1970. The shapes and sizes of seeds. Annu. Rev. Ecol. Syst. 1: 1125.CrossRefGoogle Scholar
Horak, M. J., Peterson, D. E., Chessman, D. J., and Wax, L. M. 1994. Pigweed Identification. A Pictorial Guide to the Common Pigweeds of the Great Plains. Cooperative Extension Service Pub. S80. Manhattan, KS: Kansas State University. 20 p.Google Scholar
Knezevic, Z. S., Horak, M. J., and Vanderlip, R. L. 1997. Relative time of redroot pigweed (Amaranthus retroflexus) emergence is critical in pigweed-sorghum (Sorghum bicolor) competition. Weed Sci. 45: 502508.CrossRefGoogle Scholar
Knezevic, Z. S., Weise, S. F., and Swanton, C. J. 1994. Interference of redroot pigweed (Amaranthus retroflexus L.) in corn (Zea mays L.). Weed Res. 42: 568573.CrossRefGoogle Scholar
Koutsoyiannis, A. 1973. Theory of Econometrics: An Introductory Exposition of Econometric Methods. London: MacMillan, pp. 6895.Google Scholar
Légère, A. and Schreiber, M. M. 1989. Competition and canopy architecture as affected by soybean (Glycine max) row width and density of redroot pigweed (Amaranthus retroflexus) . Weed Sci. 37: 8492.CrossRefGoogle Scholar
McLachlan, S. M. 1992. Effect of Corn Induced Shading on Redroot Pigweed Phenology, Architecture and Reproductive Ecology. . University of Guelph, Ontario, Canada. 110 p.Google Scholar
McLachlan, S. M., Tollenaar, M., Swanton, C. J., and Weise, S. F. 1993a. Effect of corn induced shading on dry matter accumulation, distribution and architecture of redroot pigweed (Amaranthus retroflexus L). Weed Sci. 41: 568573.CrossRefGoogle Scholar
McLachlan, S. M., Weise, S. F., Swanton, C. J., and Tollenaar, M. 1993b. Effect of corn induced shading and temperature on rate of leaf appearance in redroot pigweed (Amaranthus retroflexus L.). Weed Sci. 41: 590593.CrossRefGoogle Scholar
[SAS] Statistical Analysis Systems. 1987. SAS/STAT User's Guide. Version 6, 4th ed. Cary, NC: Statistical Analysis Systems Institute. 1290 p.Google Scholar
Siriwardana, G. D. and Zimdahl, R. L. 1984. Competition between barnyardgrass (Echinochloa crus-galli) and redroot pigweed (Amaranthus retroflexus) . Weed Sci. 32: 218222.CrossRefGoogle Scholar
Weaver, S. E. 1986. Factors affecting threshold levels and seed production of jimson weed (Datura stramonium L.) in soybean (Glycine max) . Weed Res. 26: 215223.CrossRefGoogle Scholar
Weaver, S. E. and McWilliams, E. L. 1980. The biology of Canadian weeds. 44. Amaranthus retroflexus L., A. powellii S. Wats. and A. hybridus L. Can. J. Plant Sci. 60:12151234.CrossRefGoogle Scholar