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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
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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 

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