Plant viruses and virus diseases, 3rd ed

Plant viruses and virus diseases, 3rd ed

chemists and highly trained workers in some of the biological sciences. A vast amount of data on the response of cells to chemicals is scatAered throu...

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chemists and highly trained workers in some of the biological sciences. A vast amount of data on the response of cells to chemicals is scatAered throughout the literature and awaits proper analysis and coordination. Caution should lx exercised in the indiscriminate transfer of results obtained on artificial systems studied in tn’tro to the elucidation of cell pharmacology. The final test of any hypothrsis must rert. OIL clspc%ments on the living cell. New and more refined methods arc nerded. Danielli’s small and timely book, notwithstanding sornc: of it,s errors and limitat,iorl*. is thought-provoking. It supplrments A. J. Clark’s .lrorlr oJ d cbion of 11rrrcl.sO?L(‘~i1.9 published in 1933. (:AHL \‘OEOTLIN, Rochester, Sew Tork Plant Viruses and Virus Diseases, 3rd Ed. By F. C. BAWDEX, Head, Plant l’atJ~ology Department, Rothamsted Experimental Station, Harpenden, Harts, England. Chronica Botanica Company, Waltham, Mass.; StecllPrt,-FIafnc,r Co., ?;ew York, S. Y. 1950. siv + 335 pp. Price $6.00. The third edition of this already classic book \vill be welcome by the virologist and the general biologist alike, particularly since the second edition has heen out of print for some years. The book has always been distinguished by its prevasive sanity and it,s critical methodological approach to a field where semantics and method have taken some of their worst beatings. It is almost inevitable that in a rapidly progressing field the exiting discoveries will tend to overwhelm the discoverers and the bystanders and to inveigle them into strange philosophical vagaries. This is especially true of borderline fields, when such problems as the structure of the atom or the naturr of life arc approached. Physicists have often been saved by their traditional training in methodological critique, favored by the rigorous quality of the mathematical tools that they USP. Only a sensitive appreciation of the level at which biology opPratc,s can save the borderline biologist from semantic and conceptual monstrosities. Bawden has been critical from the very first,, and has become increasingly so :ih IEW editions of this book appeared. The present one is, even more than the earlier ones, the work of a true biologist, in its constraint at least, if not always so in its emphasis. The author clearly appreciates the gaps between virus particles and virus reproduction, between virus composition and virus nature, between infectivity and self-replication. The mere contemplation of a virus crystal or of :m electron micrograph does not blur his awareness of the fact that the free virus particle is but one aspect of the virus, aud possibly a greatly distorted one, and that t,he really important virus aspect is that which functions as a model for reproduction of its specific configuration inside the host cell. The awareness that virology is ultimately a branch of cell physiology is ever-present in this book, although unfortunately the limited knowledge of the cellular physiopathology of plant virus reproduction (as compared, fol (axample, with t,hat of bacteriophage reproduction) prevents a more thorough discussion. bctually, the major cribicism that can be leveled at! Hawden’s book is that, it does not contain a more direct discussion of virus-host cell relationship. Host,-plant, physiology is discussed in one short chapter and covers mainly such disi(‘ouraginglj uninterpretable observations as those on the effects of virus diseases on gross phases of host metabolism. The most interesting phases of cellular physiopathology art’ discussed either under the heading of symptomatology, or in conncrtion with partic+ &xl. or with the origin of viruses.

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BOOK

REVIEWS

After an introduction giving an acceptable operational definition of virus, the book contains an almost unchanged, excellent discussion of general symptomatology and an equally clear one of virus transmission, here and there heightened by the author’s polemical style, particularly in connection with the relation between viruses and insect vectors. The following discussion of virus strains and interference phenomena does not always render full justice to the opinions of some of the active workers in this field, which has been more cultivated in the United States than in England. Serological methods and titration procedures are discussed next, followed. by four chapters on the physical properties of virus particles. These chapters, still on the same lines as in previous editions, have vastly been improved, both by revisions and by omission of some tedious technical details of chemical procedures. A commendable feature is the continued avoidance of background technical information; it is indeed refreshing not to find in a book on viruses any photograph of either a shiny electron microscope (with or without operator) or of a dismembered ultracentrifuge. One might still wish for omission, from the next edition, of the perennial photogenic fish swimming in a sea of tobacco mosaic virus. After a sensible discussion of virus taxonomy and a brief chapter on control measures written in a justifiably subdued mood, the book ends with a remarkable discussion of the origin of viruses, which, in spite of several debatable statements, exemplifies the clarifying inroad of modern genetic thinking into the field of virology. The level of plant viruses in the hierarchy of biological objects is considered, probably soundly, as that of specific cell determinants, rather than either that of secondary cell products or of full-fledged cellular entities. At the same time, the author points out how little this conclusion advances us in understanding virus origin and nature, until the problem of the genetic continuity of cell constituents in general is solved. Here is where geneticist, virologist, and biochemist are finally getting together. S. E. LURIA, Urbana, Illinois Protein ALBANESE, Academic

and Amino Acid Requirements of Mammals. Edited by ANTHONY A. Nutritional Research Laboratory, St. Lukes Hospital, New York, N. Y. Press Inc., New York, N. Y., 1950. x + 155 pp. $4.00.

The purpose of this book, as presented in the foreword by the editor, is to describe the techniques used to determine the protein and amino acid requirements of various mammals and to evaluate the significance of the results. The authors of the papers which follow develop this purpose admirably, a development which covers basic principles of protein metabolism. Each paper is reviewed briefly. “Some Species and Age Differences in Amino Acid Requirements.” By H. H. Mitchell, Division of Animal Nutrition, University of Illinois. Dr. Mitchell introduces this subject by emphasizing the unique functions of dietary amino acids: functions which are entirely anabolic in character. Since essential amino acid requirements are conditioned by the types of tissues being maintained or growing, the requirements can vary from youth to adult, from species to species. The author presents an excellent schematic development, both by word and diagram, of a theory of protein metabolism. It is based on Folin’s concept of two distinct types of protein catabolism but includes later developments, particularly those of Whipple and Schoenheimer and their associates.