Biochemistry of Herbicides Affecting Photosynthesis

This paper is an introduction to the primary effects of herbicides on photosynthetic electron transport, photophosphorylation and pigment syn­ thesis. Herbicides are not known to have primary effects on transcription, translation or carbon fixa­ tion, and the inhibition of lipid synthesis by the thiolcarbamates will not be considered since it is not restricted to the chloroplast. We will be con­ cerned mainly with the primary biochemical elfects of compounds so far as they are known, since re­ ports of gross effects on whole plants do not provide leads which can be of use in seeking out new active herbicides. We will need to concentrate on the most recent developments; a previous review [1] considers the earlier work. Throughout we shall be empha­ sizing information that might aid the synthesis of new herbicides.