Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-14T05:10:45.166Z Has data issue: false hasContentIssue false

Physiological Changes Accompanying the Death of Cocklebur Plants Treated with 2,4-D

Published online by Cambridge University Press:  12 June 2017

J. Cardenas
Affiliation:
Agronomy Department, University of Illinois, Urbana
F. W. Slife
Affiliation:
Agronomy Department, University of Illinois, Urbana
J. B. Hanson
Affiliation:
Agronomy Department, University of Illinois, Urbana
H. Butler
Affiliation:
Agronomy Department, University of Illinois, Urbana

Abstract

The hypothesis that plants treated with 2,4-dichlorophenoxyacetic acid (2,4-D) die as a consequence of abnormal growth has been examined. Cocklebur (Xanthium sp) plants spot treated on one leaf with 2,4-D show three phases of growth toward death. For the first 2 days after treatment, there is a net weight increase, largely due to abnormal growth of the axis (apex, stem, and tap root). Root and leaf growth are drastically curtailed. Between 2 and 7 days, axis growth continues primarily at the expense of leaf tissue which is induced to senesce, especially the cotyledons. The last phase between 7 and 10 days leads to collapse and withering of plants, and was not examined in detail.

Analyses for nitrogenous constituents show the usual mobilization to the axis, with early and large increases in nucleic acid. Both photosynthesis and ion absorption are initially stimulated but decline sharply after the first day. Translocation to leaves and roots is drastically reduced in favor of the proliferating axis.

The death of the plant appears to be due to suppression of normal apical growth coupled with induction of abnormal axis growth. Failure to produce new root and leaf tissue plus inadequate nutritional maintenance of existing roots and leaves lead to lack of autotrophism and eventual death. The biochemical basis for these responses appears to be with aberrant nucleic acid metabolism.

Type
Research Article
Copyright
Copyright © 1968 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. Audus, L. J. 1959. Plant Growth Substances. 2nd ed. Leonard Hill, London. 553 p.Google Scholar
2. Cooke, A. R. 1957. Influence of 2,4-D on the uptake of minerals from the soil. Weeds 5:2528.Google Scholar
3. Couch, R. W. and Davis, D. E. 1966. Effect of atrazine, bromacil, and diquat on C14O2 fixation. Weeds 14:251254.CrossRefGoogle Scholar
4. Eames, A. J. 1950. Destruction of phloem in young bean plants after treatment with 2,4-D. Amer. J. Bot. 37:840847.Google Scholar
5. Gorder, C. J. and Van der Zweep, W. 1964. Morphogenetic effects of herbicides, p. 235275. In Audus, L. J. (ed.) The Physiology and Biochemistry of Herbicides. Academic Press, New York.Google Scholar
6. Haber, A. H. 1962. Effects of indoleacetic acid on growth without mitosis and on mitotic activity in absence of growth by expansion. Plant Physiol. 37:1826.Google Scholar
7. Hanson, J. B. and Slife, F. W. 1961. How does 2,4-D kill a plant? Illinois Res. 3:34.Google Scholar
8. Hilton, J. L., Jansen, L. L., and Hull, H. M. 1963. Mechanisms of herbicide action. Ann. Rev. Plant Physiol. 14:353384.Google Scholar
9. Holdgate, D. P. and Goodwin, T. W. 1965. Quantitative extraction and estimation of plant nucleic acids. Phytochemistry 4:831843.Google Scholar
10. Key, J. L. and Hanson, J. B. 1960. Some effects of 2,4-D on soluble nucleotides and nucleic acid of soybean seedlings. Plant Physiol. 36:145152.CrossRefGoogle Scholar
11. Key, J. L., Liu, C. Y., Gifford, E. M. Jr., and Dengler, R. 1966. Relation of 2,4-D induced growth aberrations to changes in nucleic acid metabolism in soybean seedlings. Bot. Gaz. 127:8794.Google Scholar
12. Kiermayer, O. 1964. Growth responses to herbicides, p. 207233. In Andus, L. J. (ed.) The Physiology and Biochemistry of Herbicides. Academic Press, New York.Google Scholar
13. Lannie, F., Dillon, M. L., and Beard, J. W. 1950. Determination of small quantities of nitrogen in serological precipitate and other biological materials. Proc. Soc. Exptl. Med. 74:4.Google Scholar
14. Lowry, O. H., Rosebrough, M. J., Farr, A. L., and Randall, R. J. 1951. Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193:267275.Google Scholar
15. Shannon, J. C., Hanson, J. B., and Wilson, C. M. 1964. Ribonuclease levels in the mesocotyl tissue of Zea mays as a function of 2,4-dichlorophenoxyacetic acid application. Plant Physiol. 39:804809.CrossRefGoogle Scholar
16. Swenson, G. and Burstrom, H. 1960. On the influence of auxins on salt and water uptake. Physiol. Plantarum 13:846854.Google Scholar
17. Turner, W. B. and Bidwell, R. G. S. 1965. Rates of photosynthesis in attached and detached bean leaves and the effect of spraying with IAA solution. Plant Physiol. 40:446451.Google Scholar
18. Van Overbeek, J. 1964. Survey of mechanisms of herbicide action, p. 387400. In Audus, L. J. (ed.) The Physiology and Biochemistry of Herbicide Action. Academic Press, New York.Google Scholar
19. Wedding, R. T. and Black, M. K. 1962. Response of oxidation and coupled phosphorylation in plant mitochondria to 2,4-dichlorophenoxyacetic acid. Plant Physiol. 37:364370.CrossRefGoogle Scholar
20. Wolf, D. E., Vermillion, G., Wallace, A., and Algren, G. H. 1950. Effect of 2,4-D on carbohydrate and nutrient element content and on rapidity of kill of soybean plants growing at different nitrogen levels. Bot. Gaz. 112:188197.CrossRefGoogle Scholar
21. Wort, D. J. 1964. Effects of herbicides on plant composition and metabolism, p. 291334. In Audus, L. J. (ed.) The Physiology and Biochemistry of Herbicides. Academic Press, New York.Google Scholar
22. Wort, D. J. 1964. Responses of plants to sublethal concentrations of 2,4-D without and with added minerals, p. 335342. In Audus, L. J. (ed.) The Physiology and Biochemistry of Herbicides. Academic Press, New York.Google Scholar