Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-20T03:35:10.180Z Has data issue: false hasContentIssue false

Differential Susceptibility of two Pigweed (Amaranthus spp.) Species to Napropamide

Published online by Cambridge University Press:  12 June 2017

C. L. Elmore
Affiliation:
Dep. Bot., Univ. of California, Davis, CA 95616

Abstract

Differential napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide] tolerance by redroot pigweed (Amaranthus retroflexus L.) and prostrate pigweed (Amaranthus blitoides S. Wats.) was noted in field study. Redroot pigweed was readily controlled whereas prostrate pigweed was not. Germination studies in which both pigweed species were directly exposed to napropamide (0 to 25 ppm) indicated that prostrate pigweed was the most susceptible of the two species. Root growth rates of untreated prostrate pigweed were 30% greater than redroot pigweed. When seeds of both species were germinated in a 4-cm layer of napropamide in greenhouse study each species was controlled equally well. Exposure of germinating seedlings of the two pigweed species to napropamide 1 day before emergence resulted in differential control. Seedlings of redroot pigweed never developed beyond the cotyledon stage; whereas, prostrate pigweed seedlings were initially suppressed by the herbicide, but surviving plants continued to grow. An early preemergence application or mechanical incorporation of napropamide should enhance control of prostrate pigweed.

Type
Research Article
Copyright
Copyright © 1979 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Ashton, F. M. and Crafts, A. S. 1973. Amides. Pages 126146 in Ashton, F. M. and Crafts, A. S., eds. Mode of action of herbicides. John Wiley and Sons, New York.Google Scholar
2. Eshel, S., Katlan, J., and Palevitch, D. 1973. Selective action of diphenamid and napropamide in pepper (Capsicum annuum L.) and weeds. Weed Res. 13:379384.Google Scholar
3. Gray, R. A., Arneklev, R. D., and Baker, D. R. 1966. R-7465, 2-(α-naphthoxy)-N,N-diethyl propionamide, a new preemergence herbicide. Res. Prog. and Proc., West. Weed Control Conf., pp. 145146.Google Scholar
4. Gressel, J. and Segal, L. A. 1978. The paucity of plants evolving genetic resistance to herbicides: Possible reasons and explanations. J. Theor. Biol. (in press).CrossRefGoogle Scholar
5. Harper, J. L. 1960. The recruitment of seedling populations. Pages 119132 in Harper, J. L., ed. The biology of weeds, Blackwell Sci. Publ., Oxford.Google Scholar
6. Isensee, A. R., Shaw, W. C., Gentner, W. A., Swanson, C. R., Turner, B. C., and Woolson, E. A. 1973. Revegetation following massive application of selected herbicides. Weed Sci. 21:409413.Google Scholar
7. Murphy, J. J., Didriksen, J., and Gray, R. A. 1973. Metabolism of 2-(α-naphthoxy)-N,N-diethyl propionamide in tomato. Weed Sci. 21:1115.Google Scholar
8. Muzik, T. J. 1976. Influence of environmental factors on toxicity to plants. Pages 204243 in Audus, L. J., ed. Herbicides, physiology, biochemistry, ecology Vol. II, London.Google Scholar