Published online by Cambridge University Press: 12 June 2017
Many of the pathways by which weedkillers, such as 2,4–dichlorophenoxyacetic acid (2,4–D), affect plants are still obscure. Frequently the adverse effect seems to involve an alteration of metabolism, but the exact nature of this is sometimes not clear. Photosynthesis and respiration under different conditions may be either stimulated or inhibited. Other results, in which a decolorization of tissue with increasing amounts of 2,4–D was observed, suggest that the herbicide either interferes with the formation of chlorophyll, or causes increased destruction.