O. L. LANGE, P. S. NOBEL, C. B. OSMOND, and H. ZIEGLER In the original
series of the Encyclopedia of Plant Physiology, plant water relations
and photosynthesis were treated separately, and the connection between
phenomena was only considered in special chapters. O. STOCKER edited
Vol- ume III, Pjlanze und Wasser/Water Relations of Plants in 1956, and
4 years later, Volume V, Parts I and 2, Die COrAssimilation/The
Assimilation of Carbon Dioxide appeared, edited by A. PIRSON. Until
recently, there has also been a tendency to cover these aspects of plant
physiology separately in most text- books. Without doubt, this
separation is justifiable. If one is specifically inter- ested, for
example in photosynthetic electron transport, in details of photophos-
phorylation, or in carbon metabolism in the Calvin cycle, it is not
necessary to ask how these processes relate to the water relations of
the plant. Accordingly, this separate coverage has been maintained in
the New Series of the Encyclopedia of Plant Physiology. The two volumes
devoted exclusively to photosynthesis are Volume 5, Photosynthesis I,
edited by A. TREBST and M. AVRON, and Volume 6, Photosynthesis II,
edited by M. GIBBS and E. LATZKO. When consider- ing carbon assimilation
and plant water relations from an ecological point of view, however, we
have to recognize that this separation is arbitrary.