Light signals perceived by crop and weed plants

Light signals perceived by specific plant photoreceptors such as phytochromes, cryptochromes and phototropin play a central role controlling the physiology and development of weed and crop plants. Knowledge about these controls has been gained in the last decade thanks to the combination of eco-physiological experiments under conditions of natural radiation with classical photobiological techniques and genetic and biotechnological tools. This progress has important ramifications for our understanding of the physiology of crop growth and development, as well as the mechanisms of crop-weed competition. In this paper we discuss some of the recent advances in the field of environmental photomorphogenesis and highlight their agricultural implications. (C) 2000 Elsevier Science B.V. All rights reserved.