PREFACE TO VOLUME III
W i t h V o l u m e I I I , on m i n e r a l nutrition, t h e Treatise on P l a n t Physiology enters u p o n its second section, w h i c h deals w i t h t h e n u t r i - tion a n d metabolism of plants.
I n V o l u m e I I plants w e r e considered in their general relation to w a t e r a n d to solutes. Photosynthesis a n d respiration, starting from a n d r e t u r n i n g to carbon dioxide a n d w a t e r , h a v e been discussed in Volumes I A a n d IB, a n d t h e manifold processes of i n t e r m e d i a r y metabolism will be taken u p in V o l u m e IV. Therefore, V o l u m e I I I is n o w concerned solely w i t h t h e role of those elements of t h e periodic table, other t h a n carbon, hydrogen, a n d oxygen, w h i c h a r e essential to, or used b y , plants in their vital processes.
I n t h e subject of m i n e r a l nutrition, p l a n t physiology bears a close relationship to agriculture. T h e practical i m p o r t a n c e of t h e m i n e r a l nutrition of plants, t h r o u g h m a n u r i a l practices or fertilizer programs, gave to t h e emerging science of p l a n t physiology m u c h of its e a r l y i m p e t u s ; this debt to agriculture h a s been a m p l y repaid. T h i s volume, then, briefly traces the history of m i n e r a l nutrition of plants, and, as it summarizes t h e present status of knowledge, the intention is t h a t it will also point to t h e challenge of t h e future.
T h e p l a n of the treatise r e m a i n s as previously announced, a n d its aims a n d general style h a v e not changed. A g a i n t h e subject m a t t e r could only be covered b y a selected group of authors, each a n a u t h o r i t y in his own field. W h i l e each chapter of V o l u m e I I I is complete in itself, the volume as a whole should present a philosophy of p l a n t nutrition.
I n t h e difficult a t t a i n m e n t of these ends, t h e individual authors h a v e rightly exercised a large m e a s u r e of discretion in their respective chap- ters, a n d the value of t h e volume t h u s rests u p o n their scholarly work.
T o all these contributors the editor is greatly indebted.
Although t h e various chapters i n this volume a r e conveniently grouped together, this is nevertheless a somewhat a r b i t r a r y device, for, in their role, t h e m i n e r a l elements also touch all aspects of p l a n t be- havior. T h u s h a r d l y a physiological topic can be considered w i t h o u t at some point disclosing a connection w i t h , or a decisive role for, some essential inorganic element. I n fact, it is these interactions t h a t give m u c h of t h e c u r r e n t impetus to t h e subject of m i n e r a l nutrition.
T h e n o w familiar form of t h e indexes is preserved in this volume of t h e treatise. Subject a n d A u t h o r Indexes a n d a n Index of P l a n t N a m e s are again included. I n the over-all plan of the entire treatise the same
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viii PREFACE
conventions concerning the use of p l a n t n a m e s are applied in this as in t h e previous volumes, a n d the application of these conventions h a s again been supervised b y Dr. W . J. Dress, w h o has also prepared t h e Index of P l a n t N a m e s . T h e Subject Index for V o l u m e I I I w a s compiled b y M r . Richard D. Holsten. For all this help t h e editor is also grateful.
Since the authors completed their manuscripts for this volume, the rules on n o m e n c l a t u r e of enzymes a n d coenzymes h a v e been reviewed b y a Commission of the International U n i o n of Biochemistry. T h e recommendations of this commission are s u m m a r i z e d in Science (1962) 137, 4 0 5 - 4 0 8 . According to these recommendations, such time-honored n a m e s as cozymase; coenzyme I (Co I ) ; coenzyme I I (Co I I ) ; diphos- phopyridine nucleotide ( D P N ) ; triphosphopyridine nucleotide ( T P N ) should no longer be used, although, for lack of a suitable alternative, coenzyme A (CoA) is still permissible! Therefore, in this volume the older a n d well understood practices h a v e of necessity been retained, although it is a p p a r e n t t h a t plant physiologists m u s t n o w l e a r n to rec- ognize these familiar enzymes a n d coenzymes u n d e r their n e w a n d approved n a m e s .
W h e r e v e r possible, t h e text is illustrated b y figures a n d tables which are reproduced from original sources. T h e purpose of this is to present enough of both t h e evidence a n d the analysis of it to reduce t h e need continually to consult t h e original sources, w h i c h are also cited. Each author has obtained prior permission to include in his chapter the previously published m a t e r i a l which h e has used, a n d the form of cita- tion in the text a n d in the bibliography is held to convey t h e acknowl- edgments a n d the thanks of both authors a n d editor for t h e use of these materials. T o list separately all such cases in a w o r k of this sort would be a formidable task indeed.
Finally, the editor again wishes to acknowledge t h e v e r y real help h e has received from the personnel of Academic Press.
F. C. Steward Ithaca, N e w York
F e b r u a r y , 1963
