Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-27T22:38:39.007Z Has data issue: false hasContentIssue false
  • English
  • Français

Reflections on investigating dormancy-breaking chemicals—a balance of logic and luck

Published online by Cambridge University Press:  20 January 2017

Marc A. Cohn
Marc A. Cohn*
Affiliation:
Department of Plant Pathology and Crop Physiology, 302 Life Science Building, Louisiana State University Agricultural Center, Baton Rouge, LA 70803; mcohn@lsu.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

In many cases, the logical presentation of scientific results masks the actual unfolding of experimental progress. Our work to identify the mechanisms by which chemicals break red rice seed dormancy is presented as an example. Doing the simplest experiments first, allowing the data to drive subsequent work, frequent and aggressive study of published literature, and examination of potentially key findings using multiple, interlocking strategies have been the keys to defining the relationship between the structure and action of dormancy-breaking chemicals. Our experiments show that chemical activity is dependent upon the lipophilicity as well as the nature and position of functional groups. However, the chemical that is applied to a dormant seed is not necessarily the chemical that actually breaks dormancy. A combination of approaches using structure–activity studies, metabolic inhibitors, and physiological measurements indicate that alcohols must first be metabolized to carboxylic acids to elicit germination of red rice. This report summarizes these findings as a personal account, illustrating the importance of logic, luck, and imagination in scientific discovery, as well as to highlight some important lessons about conducting research.

Keywords

Red rice, Oryza sativa L. ORYSADormancy-breaking chemicalsgerminationseed dormancy
Type
Research Article
Information
Weed Science , Volume 50 , Issue 2 , April 2002 , pp. 261 - 266
Copyright
Copyright © 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

Allen, P. S. and Meyer, S. E. 2002. Ecology and ecological genetics of seed dormancy in Bromus tectorum . Weed Sci. 50:241–247.Google Scholar
Ariëns, E. J. 1971. A general introduction to the field of drug design. Pages 1–270 In Ariëns, E. J., ed. Drug Design: Volume 1. New York: Academic Press.Google Scholar
Biswas, J. K., Ando, H., and Kakuda, K.- I. 2001. Effect of volatile fatty acids on seedling growth of anoxia-tolerant rice (Oryza sativa L.) genotypes. Soil Sci. Plant Nutr. 47:87–100.CrossRefGoogle Scholar
Bradford, K. J. 1996. Population-based models describing seed dormancy behaviour: implications for experimental design and interpretation. Pages 313–339 In Lang, G. A., ed. Plant Dormancy: Physiology, Biochemistry and Molecular Biology. Wallingford, U.K.: CAB International.Google Scholar
Carafoli, E., Santella, L., Branca, D., and Brini, M. 2001. Generation, control, and processing of cellular calcium signals. Crit. Rev. Biochem. Mol. Biol. 36:107–260.Google Scholar
Clark, G. B., Thompson, G., and Roux, S. J. 2001. Signal transduction mechanisms in plants: an overview. Curr. Sci. 80:170–177.Google Scholar
Cohn, M. A. 1983. pH dependent activity of dormancy-breaking chemicals. Agron. Abstr. 118.Google Scholar
Cohn, M. A. 1987. Mechanisms of physiological seed dormancy. Pages 14–20 In Frazier, G. W. and Evans, R. A., eds. Seed and Seedbed Ecology of Rangeland Plants. Washington, D.C.: USDA-ARS.Google Scholar
Cohn, M. A. 1990. Factors influencing the efficacy of dormancy-breaking chemicals. Pages 261–267 In Taylorson, R. B., ed. Recent Advances in Development and Germination of Seeds, New York: Plenum Press.CrossRefGoogle Scholar
Cohn, M. A. 1993. Chemical structure versus physiological activity: studies of dormancy-breaking chemicals for seeds. Search 28:1–6.Google Scholar
Cohn, M. A. 1996a. Operational and philosophical decisions in seed dormancy research. Seed Sci. Res. 6:147–153.CrossRefGoogle Scholar
Cohn, M. A. 1996b. Chemical mechanisms of breaking seed dormancy. Seed Sci. Res. 6:95–99.Google Scholar
Cohn, M. A. 1997. QSAR modeling of dormancy-breaking chemicals. Pages 289–295 In Ellis, R. H., Black, M., Murdoch, A. J., and Hong, T. D., eds. Basic and Applied Aspects of Seeds. Dordrecht, The Netherlands: Kluewer Academic.Google Scholar
Cohn, M. A., Butera, D. L., and Hughes, J. A. 1983. Seed dormancy in red rice. III. Response to nitrite, nitrate, and ammonium ions. Plant Physiol. 73:381–384.Google Scholar
Cohn, M. A., Chiles, L. A., Hughes, J. A., and Boullion, K. J. 1987. Seed dormancy in red rice. VI. Monocarboxylic acids: a new class of pH-dependent germination stimulants. Plant Physiol. 84:716–719.Google Scholar
Cohn, M. A., Church, D. F., Ranken, J., and Sanchez, V. 1991. Hydroxyl group position governs activity of dormancy-breaking chemicals. Plant Physiol. S-96:63.Google Scholar
Cohn, M. A. and Hilhorst, H.W.M. 2000. Alcohols that break seed dormancy: the anesthetic hypothesis, dead or alive? Pages 259–274 In Viemont, J. D. and Crabbe, J., eds. Dormancy in Plants: From Whole Plant Behaviour to Cellular Control. Wallingford, UK: CAB Publishing.Google Scholar
Cohn, M. A. and Hughes, J. A. 1981. Seed dormancy in red rice. I. Effect of temperature on dry-afterripening. Weed Sci. 29:402–404.Google Scholar
Cohn, M. A. and Hughes, J. A. 1986. Seed dormancy in red rice. V. Response to azide, cyanide, and hydroxylamine. Plant Physiol. 80:531–533.Google ScholarPubMed
Cohn, M. A., Jones, K. L., Chiles, L. A., and Church, D. F. 1989. Seed dormancy in red rice. VII. Structure-activity studies of germination stimulants. Plant Physiol. 89:879–882.Google Scholar
Corbineau, F., Gouble, B., Lecat, S., and Côme, D. 1991. Stimulation of germination of dormant oat (Avena sativa L.) seeds by ethanol and other alcohols. Seed Sci. Res. 1:21–28.Google Scholar
Dunand, R. T. 1973. Dormancy and Gibberellin-induced Amylase Activity in Rice. . Louisiana State University, Baton Rouge.Google Scholar
Evenari, M. 1984. Seed physiology: its history from antiquity to the beginning of the 20th century. Bot. Rev. 50:119–142.Google Scholar
Footitt, S. and Cohn, M. A. 1992. Seed dormancy in red rice. VIII. Embryo acidification during dormancy-breaking and subsequent germination. Plant Physiol. 100:1196–1202.Google Scholar
Footitt, S. and Cohn, M. A. 2001. Developmental arrest: from sea urchins to seeds. Seed Sci. Res. 11:3–16.CrossRefGoogle Scholar
Footitt, S., Vargas, D., and Cohn, M. A. 1995. Seed dormancy in red rice. X. A 13-C NMR study of metabolism of dormancy-breaking chemicals. Physiol. Plant. 94:667–671.CrossRefGoogle Scholar
French, R. C., Kujawski, P. T., and Leather, G. R. 1986. Effect of various flavor-related compounds on germination of curly dock seed (Rumex crispus) and curly dock rust (Uromyces rumicis). Weed Sci. 34:398–402.Google Scholar
French, R. C. and Leather, G. R. 1979. Screening of nonanal and related flavor compounds on the germination of 18 species of weed seed. J. Agric. Food Chem. 27:828–832.Google Scholar
Goss, W. L. and Brown, E. 1939. Buried red rice. J. Am. Soc. Agron. 31:633–637.Google Scholar
Hansch, C. and Leo, A. 1979. Substituent Constants for Correlation Analysis in Chemistry and Biology. New York: John Wiley. 339 p.Google Scholar
Hilhorst, H.W.M. and Cohn, M. A. 2000. Are cellular membranes involved in the control of seed dormancy. Pages 275–289 In Viemont, J. D. and Crabbe, J., eds. Dormancy in Plants: From Whole Plant Behaviour to Cellular Control. Wallingford, UK: CAB Publishing.Google Scholar
Lieber, C. S. 1997. Cytochrome P-4502E1: its physiological and pathological role. Physiol. Rev. 77:517–544.Google Scholar
Lin, T. Y. 1997. The Metabolism of Dormancy-breaking Compounds and its Role in Dormancy-breaking Processes. . Louisiana State University, Baton Rouge.Google Scholar
Lin, T. Y. and Cohn, M. A. 1997. The involvement of alcohol oxidation via ADH in the seed dormancy-breaking process. Plant Physiol. S-114:294.Google Scholar
Palevitch, D. and Thomas, T. H. 1976. Enhancement by low pH of gibberellin effects on dormant celery seeds and embryoless half-seeds of barley. Physiol. Plant. 37:247–252.Google Scholar
Roberts, E. H. and Smith, R. D. 1977. Dormancy and the pentose phosphate pathway. Pages 385–411 In Khan, A. A., ed. The Physiology and Biochemistry of Seed Dormancy and Germination. Amsterdam: Elsevier/North-Holland.Google Scholar
Simpson, G. M. 1990. Seed Dormancy in Grasses. Cambridge, UK: Cambridge University Press.Google Scholar
Taylorson, R. B. 1987. Environmental and chemical manipulation of weed seed dormancy. Rev. Weed Sci. 3:135–154.Google Scholar
Taylorson, R. B. 1988. Anaesthetic enhancement of Echinochloa crus-galli (L.) Beauv. seed germination: possible membrane involvement. J. Exp. Bot. 39:50–58.Google Scholar
Taylorson, R. B. 1989. Responses of redroot pigweed (Amaranthus retroflexus) and witchgrass (Panicum capillare) seeds to anesthetics. Weed Sci. 37:93–97.Google Scholar
Taylorson, R. B. and Hendricks, S. B. 1979. Overcoming dormancy in seeds with ethanol and other anaesthetics. Planta 145:507–510.Google Scholar
Toole, V. K. and Cathey, H. M. 1961. Responses to gibberellin of light-requiring seeds of lettuce and Lepidium virginicum . Plant Physiol. 36:663–671.Google Scholar
Walker-Simmons, K. 1998. Protein kinases in seeds. Seed Sci. Res. 8:193–200.Google Scholar