Approaches to and Definitions of the Mechanisms of Action of Herbicides

Abstract

When raising the question of the mechanism of the action of herbicides, the type of approach and the type of answer will differ considerably depending on the viewpoint of the investigator. An answer to a certain pre-emergence herbicide might be that the compound is taken up by the imbibing seed and severely inhibits root growth of the emerging seedling (e.g. p. 148); for a post-emergence herbicide the answer might be that it rapidly dessicates established leaf tissue, but only in the light (e.g. p. 89). These answers use visual information. However, a vast amount of information has been accumulated over the recent years on the cytological, physiological, biochemical, and molecular aspects of herbicide action on different plant systems, thus enabling us to answer the question of the mechanism of this action much more precisely.