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A Proposed Mechanism for Diuron-Induced Phytotoxicity

Published online by Cambridge University Press:  12 June 2017

Charles E. Stanger Jr.  and
Arnold P. Appleby
Charles E. Stanger Jr.
Affiliation:
Dep. of Crop. Sci., Oregon State Univ., Corvallis, Oregon 97331
Arnold P. Appleby
Affiliation:
Dep. of Crop. Sci., Oregon State Univ., Corvallis, Oregon 97331
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Abstract

Chloroplasts isolated from spinach (Spinacia oleracea L.) leaves were used to study mechanisms of toxicity from 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron). Light was needed to initiate diuron injury. The addition of ascorbate plus 2,6-dichlorophenylindolephenol (DPIP) as an electron donor system completely protected the chloroplasts from diuron-induced toxicity. The protective effect from the electron donor system occurred only in functional chloroplasts. Diuron caused rapid and extensive chlorophyll degradation at chlorophyll: diuron ratios of 200:1 and lower. At higher ratios the effect was much less measurable. The electron donor system gave complete protection in the presence of methylamine HCl, a known inhibitor of photophosphorylation, indicating that a deficiency of ATP was not the primary cause of diuron toxicity. Time-course studies showed that carotenoid pigments began to degrade before initiation of chlorophyll degradation. These results are interpreted as supporting a hypothesis that diuron induces phytotoxicity by catalyzing lethal photosensitized oxidations in the cell. This may occur as a result of (a) a greater concentration of oxidized chlorophyll caused by an interruption of electron flow and (b) an inhibition of NADPH formation which is necessary to maintain a functional carotenoid protective mechanism.

Type
Research Article
Information
Weed Science , Volume 20 , Issue 4 , July 1972 , pp. 357 - 363
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

1. Arnon, D. I. 1949. Copper enzymes in isolated chloroplasts. Polyphenoloxidase in Beta vulgaris . Plant Physiol. 24:1–15.Google Scholar
2. Aronoff, S. and Mackinney, G. 1943. The photooxidation of chlorophyll. J. Amer. Chem. Soc. 65:956–958.Google Scholar
3. Ashton, F. M. 1965. Relationship between light and toxicity symptoms caused by atrazine and monuron. Weeds 13:164–169.Google Scholar
4. Ashton, F. M., Gifford, E. M. Jr., and Bisalputra, T. 1963. Structural changes in Phaseolus vulgaris induced by atrazine. I. Histological changes, II. Effects on fine structure of chloroplasts. Bot. Gaz. 124:329–343.Google Scholar
5. Bamji, M. S. and Krinsky, N. I. 1965. Carotenoid deepoxidations in algae. II. Enzymatic conversion of antheraxanthin to zeaxanthin. J. Biol. Chem. 240:467–470.CrossRefGoogle ScholarPubMed
6. Bishop, N. I. 1960. Cited by Gaffron, H. Energy storage: photosynthesis, p. 3–277. In Steward, F. C. (ed.) Plant physiology. Vol. IB. Academic Press, New York.Google Scholar
7. Bishop, N. I. 1958. The influence of the herbicide, DCMU, on the oxygen-evolving system of photosynthesis. Biochim. Biophys. Acta 27:205–206.CrossRefGoogle ScholarPubMed
8. Brenchley, R. G. and Appleby, A. P. 1971. Effect of magnesium and photoperiod on atrazine toxicity to tomatoes. Weed Sci. 19:524–525.CrossRefGoogle Scholar
9. Duysens, L. N. M. 1963. Studies on primary reactions and hydrogen or electron transport in photosynthesis by means of absorption and fluorescence difference spectrophotometry of intact cells, p. 1–17. In Kok, B. (chm.) Photosynthetic mechanisms of green plants. Nat. Acad. Sci., — Nat. Res. Counc., Publ. No. 1145. Washington, D.C. Google Scholar
10. Gast, A. 1958. Uber Pflanzenwachstrumsregulatoren. Beitrage zur Kenntnis der phytotoxischen Wirkung von Triazinen. Experientia 14:134–136.Google Scholar
11. Good, N. E. 1960. Activation of the Hill reaction by amines. Biochim. Biophys. Acta 40:502–517.Google Scholar
12. Good, N. E. 1961. Inhibitors of the Hill reaction. Plant Physiol. 36:788–803.CrossRefGoogle ScholarPubMed
13. Griffiths, M., Sistrom, W. R., Cohen-Bazire, G., and Stanier, R. Y. 1955. Function of carotenoids in photosynthesis. Nature 176:1211–1215.CrossRefGoogle ScholarPubMed
14. Izawa, S. and Good, N. E. 1965. The number of sites sensitive to 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea and 2-chloro-4-(2-propylamino)-6-ethylamino-s-triazine in isolated chloroplasts. Biochim. Biophys. Acta 102:20–38.Google Scholar
15. Krinsky, N. I. 1966. The role of carotenoid pigments as protective agents against photosensitized oxidations in chloroplasts, p. 423–430. In Goodwin, T. W. (ed.) Biochemistry of chloroplasts. Vol. 1. Academic Press, New York.Google Scholar
16. Krinsky, N. I. and Gordon, A. 1965. The epoxidation of zeaxanthin to antheraxanthin in Euglena gracilis . Federation Proc. 24:232.Google Scholar
17. Laber, L. J. and Black, C. C. 1969. Site-specific uncoupling of photosynthetic phosphorylation in spinach chloroplasts. J. Biol. Chem. 244:3463–3467.Google Scholar
18. Levine, R. P. 1969. The mechanism of photosynthesis. Sci. Amer. 221(6):58–70.Google Scholar
19. Rabinowitch, E. and Govindjee, . 1969. Photosynthesis. John Wiley and Sons, New York. 273 p.Google Scholar
20. Schenck, G. O. 1948. Zur theorie der photosensibilisierten reaktion mit molekularem sauerstoff. Naturwissenschaften 35:28–29.Google Scholar
21. Schwartz, M. 1966. N-tetramethyl-p-phenylenediamine as a catalyst of photophosphorylation. Biochim. Biophys. Acta 112:204–212.Google Scholar
22. Sweetser, P. B. and Todd, C. W. 1961. The effect of monuron on oxygen liberation in photosynthesis. Biochim. Biophys. Acta 51:504–508.Google Scholar
23. Teale, F. W. J. and Weber, G. 1957. Role of carotenoids in energy migration and photo-oxidation in chlorophyll systems, Proc. Biochem. Soc. In Biochem. J. 66:8P.Google Scholar
24. Vernon, L. P. and Zaugg, W. S. 1960. Photoreductions by fresh and aged chloroplasts: Requirement for ascorbate and 2,6-dichlorophenolindophenol with aged chloroplasts. J. Biol. Chem. 235:2728–2733.Google Scholar
25. Wessels, J. S. C. and Van der Veen, R. 1956. The action of some derivatives of phenylurethan and of 3-phenyl-1,1-dimethylurea on the Hill reaction. Biochim. Biophys. Acta 19:548–549.Google Scholar