Phytochrome And Photoregulation In Plants

It is perhaps not surprising that plants have evolved a mechanism to sense the light environment about them and to modify growth for optimal use of the available `life-giving' light. Green plants, and ultimately all forms of life, depend on the energy of sunlight fixed during photosynthesis. Unlike animals that use behaviour to find food, sedentary plants use physiology to optimize their growth and development for light absorption. By appreciating the quality, quantity, direction and duration of light, plants can control such complex processes as germination, growth and flowering. To perceive the light environment several receptor pigments have evolved, including the red/far-red reversible phytochrome and the blue/UV-absorbing photoreceptors (Part 1). The quantification of light (Part 2) and importance of instrumentation for photomorphogenesis research are introduced in Part 3. Isolation and characterization of phytochrome is a classic example of how photobiological techniques can predict the nature of an unknown photoreceptor. Current knowledge of the phytochrome photoreceptor family is given in Part 4 and that of blue/UV receptors in Part 5. Part 6 deals with the coaction of photoreceptors. The light environment and its perception is addressed in Part 7. Molecular and genetic approaches and the photoregulation of gene expression compose Part 8. Part 9 contains further selected topics: photomodulation of growth phototropism, photobiology of stomatal movements, photomovement, photocontrol of flavonoid biosynthesis, photobiology of fungi and photobiology of ferns. The 28 chapters written by leading experts from Europe, Israel, Japan and the USA, provide an advanced treatise on the exciting and rapidly developing field of plant photomorphogenesis.

Phytochrome detection and isolation; The properties of phytochrome; Phytochrome controlled responses; Mode of action of phytochrome; Some practical exercises.

This book explores the ways in which plants detect, interpret and respond to the natural light environment.

Proceedings of the NATO Advanced Research Workshop on Phytochrome Properties and Biological Action held in Chichester, U.K., July 22-27, 1990

Plants as sessile organisms have evolved fascinating capacities to adapt to changes in their natural environment. Arguably, light is by far the most important and variable environmental factor. The quality, quantity, direction and duration of light is monitored by a series of photoreceptors covering spectral information from UVB to near infrared. The response of the plants to light is called photomorphogenesis and it is regulated by the concerted action of photoreceptors. The combined techniques of action spectroscopy and biochemistry allowed one of the important photoreceptors – phytochrome – to be identified in the middle of the last century. An enormous number of physiological studies published in the last century describe the properties of phytochrome and its function and also the physiology of blue and UV-B photoreceptors, unidentified at the time. This knowledge was summarized in the advanced textbook “Photomorphogenesis in Plants” (Kendrick and Kronenberg, eds., 1986, 1994). With the advent of molecular biology, genetics and new molecular, cellular techniques, our knowledge in the field of photomorphogenesis has dramatically increased over the last 15 years.