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Glyphosate and Paraquat Effects on Weed Seed Germination and Seedling Emergence

Published online by Cambridge University Press:  12 June 2017

G. H. Egley
Affiliation:
South. Weed Sci. Lab., Agric Res. Serv., U. S. Dep. Agric., Stoneville, MS 38776
R. D. Williams
Affiliation:
South. Weed Sci. Lab., Agric Res. Serv., U. S. Dep. Agric., Stoneville, MS 38776

Abstract

Glyphosate [N-(phosphonomethyl)glycine] (30, 125, 250 mg/L) in petri dishes had no effect on germination of prickly sida (Sida spinosa L.), velvetleaf (Abutilon theophrasti Medic), barnyardgrass [Echinocloa crus-galli (L.) Beauv.] and johnsongrass [Sorghum halepense (L.) Pers.] seeds, but additional experimentation indicated that glyphosate stimulated germination of redroot pigweed (Amaranthus retroflexus L.) seeds. Paraquat (1,1′-dimethyl-4,4′-bipyridinium ion) (30, 125, 250 mg/L) did not affect germination of the three broadleaf species, but inhibited johnsongrass and barnyardgrass germination. In the greenhouse, soil surface applications of glyphosate (1.1, 2.2, 9.0 kg/ha) did not significantly affect emergence of these five weed species when they were on or beneath the soil surface at time of treatment. Paraquat (same rates) did not affect broadleaf weed emergence but some rates inhibited grass weed emergence when the seeds were treated while on the soil surface. It is unlikely that normal field use rates of glyphosate will influence weed emergence; whereas paraquat may inhibit the emergence of some grass weeds if the herbicide contacts seeds on the soil surface.

Type
Research Article
Copyright
Copyright © 1978 by the Weed Science Society of America 

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References

Literature Cited

1. Appleby, A. P. and Brenchley, R. G. 1968. Influence of paraquat on seed germination. Weed Sci. 16:484485.Google Scholar
2. Coats, G. E., Funderburk, H. H. Jr., Lawrence, J. M., and Davis, D. E. 1966. Factors affecting persistence and inactivation of diquat and paraquat. Weed Res. 6:5866.Google Scholar
3. Evans, R. A., Eckert, R. E. Jr., and Kay, B. L. 1967. Wheatgrass establishment with paraquat and tillage on Downy Brome ranges. Weeds 15:5055.Google Scholar
4. Kay, B. L. and Owen, R. E. 1970. Paraquat for range seeding in Cismontane California. Weed Sci. 18:238244.Google Scholar
5. Klingman, D. L. and Murray, J. J. 1976. Germination of seeds of turfgrasses as affected by glyphosate and paraquat. Weed Sci. 24:191193.Google Scholar
6. Moshier, L., Turgeon, A. J., and Penner, D. 1976. Effects of glyphosate and siduron on turfgrass establishment. Weed Sci. 24:445448.Google Scholar
7. Sprankle, P., Meggitt, W. F., and Penner, D. 1975. Rapid inactivation of glyphosate in the soil. Weed Sci. 23:224228.Google Scholar
8. Warboys, L. B. and Ledson, S. 1965. The effect of paraquat treated grass mulch on the rate of emergence and growth of barley, rape, and perennial ryegrass seedlings. J. Br. Grassland Soc. 20:188189.Google Scholar