Book Reviews

Deacon - Modern Mycology

Fine -Morel Tales: The Culture of Mushrooming

Dick - Straminipilous Fungi

Kurtzman & Fell - The Yeasts

Mycologist 13 (1999): pp 189-191.

This is an attractive, well produced book ‹ the cover is a photograph, on a dark background, of Lycoperdon releasing a cloud of spores ‹ that invites being picked up and perused. The audience for the book, however, is hard to define. It is not suitable for the beginning student in microbiology or biotechnology because it does not provide a satisfactory exposition of fungal morphology and classification but it might a useful adjunct for a full semester mycology course, if such still exists, to introduce a wide range of contemporary topics. The contents are divided into 14 Chapters: 1 Introduction; 2 Structure and ultrastructure; 3 Fungal growth; 4 Differentiation; 5 Nutrition; 6 Metabolism; 7 Environmental conditions for growth, and tolerance of extremes; 8 Genetics; 9 Spores, spore dormancy and spore dispersal; 10 Fungal decomposer communities; 11 Fungal interactions: mechanisms, relevance and practical exploitation; 12 Fungi as plant parasites; 13 Fungal parasites of humans, insects and nematodes; 14 Prevention and control of fungal growth. Besides the many black and white diagrams and photographs there is also, toward the end, an inserted six page colour section of figures relevant to the topics in various chapters.
   The first paragraph of 1 Introduction sets out the book's orientation and its general arrangement: "Fungi are a unique group of organisms, different from all other in their behaviour and cellular organization. The uniqueness of fungi is a prominent feature of this book, which adopts a functional rather than a taxonomic approach [emphasis added]. In the first part of the book [Chapters 2-8], we deal with the growth, physiology, behaviour and genetics of fungi, including their roles in biotechnology. In the second part [Chapters 9-13] we cover the main activities of fungi ‹ as decomposers of organic matter, spoilage agents, plant pathogens, pathogens of humans and biological control agents of pests and pathogens. A final chapter [14] is devoted to the major ways of preventing and controlling fungal growth, as this presents a major challenge in modern mycology. However, to place all this in perspective, we begin with an overview of the fungi and an outline of the major fungal groups."
   The overview (pp 1-11) is divided into four major sections ‹ Towards a definition of fungi, Growth forms of fungi, Activities of fungi, Fungi in Biotechnology ‹ that are, in turn, subdivided into a number of headed brief subsections covering topics to be treated in subsesquent chapters. A number of species are cited as examples which, to the uninitiated student, will be nothing more than unfamilar names.
   Before critiqueing the systematic part (pp 11-27), it is appropriate to note that throughout the whole text phyla (taxa ending in '-mycota') are spelled with a lower case initial letter and the terms are used more or less vernacularly. This is not only incorrect but confusing because phyla, and all other taxa above the species, start with a capital letter and have technical circumscriptions, the limits of which depend on respective authors, while common names, such as discomycetes, are lower cased and used more generally.
   The Ascomycota synopsis is not edifying. The Sexual reproduction digest does not present or explain: the haplo-dikaryotic life cycle of the euascomycetes (fruitbody initiation, ascogenous hyphae, crozier development, ascospore formation); that Neurospora crassa (Fig 1.8) is heterothallic; nor that most 'naked' yeast asci are 4-spored. The Deuteromycota, treated between the Ascomycota and Basidiomycota, are stated to be "the 'asexual' stages of ascomycota." (p 22) with a "Somatic stage as for the ascomycota." (p 24), notwithstanding that some Basidiomycota may form conidia (p 26). This circumscription, besides excluding all those hyphomycetes with clamp connections, also bars such important basidiomycetous yeasts as Cryptococcus, Malassezia, Rhodotorula, and Trichosporon, not to mention ustomycete yeast phases.
   The basidiomycete gloss is, for me, the least satisfactory. The systematics of this group of fungi has been the subject of intense contemporary scrutiny. It is now generally accepted that it is composed of two major segments: a natural assemblage, the basidiomycetes proper, and the polyphyletic ustomycetes, the smuts (given only passing mention in the book) and smut-like fungi. These moieties, recognized taxonomically, are either phyla of a basidiomycete subkingdom or subphylla of a singular Basidiomycota. The diverse ustomycetes are characteristically dimorphic and have other morphological and molecular biological traits that set them apart from the former. The coherent basidiomycetes proper are distinguished by discrete basidial and dolipore/parenthesome septal morphologies whose several combinations distinguish the major groups; only two orders are dimorphic: Filobasidiales and Tremellales. In the first subsection, p 26, on the Somatic stage, it is said that mycelia Œsometimes¹ have clamp connections, but in theSexual reproduction section clamps are not mentioned as being characteristic of dikaryons nor are they shown in the very poor life cycle diagram (Fig 1.10); basidiospore formation and discharge are not treated anywhere in the book. Teliospores are not included among the rust spore types shown in this figure and the Œexplanation¹ of the life cycle of Puccinia graminis in the legend is insufficient; it does not mention spermatia. The citation of Coccidioides immitis in the Ecology section is anomalous.
   The subsequent chapters, irrespective of their individual merits, suffer from this very inadequate and unsatisfactory taxonomic underpinning for the various taxa they mention and discuss. Some chapters, as well, also contain a number of faulty or incomplete statements that fail to convey an accurate picture of the fungi.
   In 2 Structure and ultrastructure Golgi bodies are said to be a component of hyphae and yeast cells: yes, for the chromistan Oomycota (Figs, 2.2, 2.3); no, for the (true) Fungi (Figs 2.1, 2.4, 2.7), except for some chrytrids. The section on yeasts gives three examples of non-dimorphic, budding forms: ³Saccharomyces cerevisiae (ascomycota), Candida spp. (deuteromycota) and Sporobolomyces roseus (basidiomycota).² The last named, however, is an obligate anamorph and should, in this list, be grouped with Candida (an ascomycetous anamorph); all basidiomycete yeasts that produce teleomorphs are, of necessity, dimorphic. The discussion of budding is restricted to the first named and there is no explanation here, or elsewhere, of the very different mode of budding in basidiomycete yeasts. In the description of basidiomycete septa, parenthesomes are said to be ³bracket-shaped membranous structures² which have pores: they are, in fact, dome-shaped and may also lack pores or be vesiculate; [cultural note ‹ Œbrackets¹ is British English for Œparentheses¹].
   In 3 Fungal growth, the Wall-lytic enzymes section (p 51) makes no reference to Bartnicki-Garcia¹s lysis and synthesis model and his extensive studies in the latter part of the 1980¹s. The text and Fig 3.10 of The yeast cell cycle section do not explain that the nuclear envelope persists during division and that the daughter SPBs generate two kinds of microtubules (mts) as they migrate to opposite poles: continuous mts between them and discontinuous mts that attach to chromosomes which, in turn, do not condense or move to form a metaphase plate.
   In 4 Differentiation,Cryptococcus albidus, C. neoformans, and Taphrina deformans should also have been included in Table 4.1 listing dimorphic fungi. In the several passing references to Candida albicans no reference is made to Soll¹s extensive studies of dimorphism in this species. The Sexual development section (p 82) introduces, in a single paragraph, bipolar and tetrapolar compatibility and idiomorphs. In Fig 4.15, showing steps in clamp formation characteristic of ³some², actually most, basidiomycetes, the fourth stage is labeled ³Clamp branch sealed off by septum²: but at this time two septa are formed, that of the clamp and that dividing the hyphal cell; this is the (unmentioned) phylogenetic analogy with the crozier system. Later, in the section on Development of fruitbodies [in] Schizophyllum commune (pp 86-87) Table 4.2 gives the signal events of tetrapolar compatibility but the text makes no mention of J. R. Raper¹s extensive pioneering studies that, along with those of Wessels, elucidated the key elements of this ontogeny. Nor are they cited in 8 Genetics.
   Chapters 5-14 are mostly outside my general experience and competence but they appear authoritative and well illustrated. In 9 Spores, however, a lot of space and figures (diagrams and electron micrographs) is allotted to zoospores (pp 171-177) while terrestrial species are given short shrift. For example, the statement (p 179) that ³The toadstool projects into turbulent air and drops the spores from the gills or pores (Fig 9.11).² does these fungi little justice; the Agaricus figure is more an icon than an informative diagram. First, of course, inter-hymenial air is very still; second, the exquisite ontogeny of basidiospore formation (Corner¹s ampoule effect), discharge (the apicular bubble/drop mechanism), and trajectory (Buller¹s sporabola) should not be denied the student. It is also a disappointment that mushroom poisoning is not included except for the passing references to amatoxins, muscarine, phalloin, and phallotoxins (pp 45, 115).
   This book, these faults not withstanding, does have a number of excellent précis in all of its chapters but it requires a knowledgeable lecturer to guide the student through them. Many of the shortcomings cited above can be compensated for by using jointly Ingold and Hudson¹s similarly sized and priced The Biology of Fungi (Chapman & Hall, 1993, £15.95). Taken together, this pair of books can provide students an excellent vade-mecum to the fungi.

R. T. Moore

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SGM Quarterly 25 (1998), p. 179

Morel Tales: The Culture of Mushrooming by G.A. Fine. Published by Harvard University Press (1998). £23.50/US$ . pp. 324 ISBN: 0-674-08935-9

A delightful ethnographic analysis of the culture of field mycologists (mushroomers) as a paradigm of the customs of naturalists in general (birdwatchers, ramblers, botany clubs etc.). Fine argues that 'Nature' is not real per se but is, instead, a collective human interpretation of the external world. From the vantage point of having been an active member of the Minnesota Mycological Society he examines how individuals experience the natural environment, how amateurs think and talk about the mushrooms they collect, the social features of foraying and consuming mushrooms, the social colloquy involved in 'naturework', how nature-pursuit organisations are experienced, and how field mycologists view and interact with the general public, commercial collectors, and professional mycologists.
   This book is strongly recommended to all introspective naturalists, particularly field mycologists and their professional colleagues, and should be a priority aquisition for any library (public, secondary school, college, university) with a natural history collection.

R. T. Moore

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Mycological Research 777 (2002): pp 999-888.

Straminipilous Fungi by Michael W. Dick (2001). Pp. 670. ISBN 0-7923-6780-4 (hardback). Kluwer Academic Publishers. Dordrecht, The Netherlands.

The biflagellate fungi, chromophyte algae (diatoms, brown seaweeds, chrysophytes, yellow-green algae and other photosynthetic groups), the labyrinthulids and thraustochytrids, and free-living marine protists comprise, on the basis of molecular sequencing, a natural, monophyletic group worthy of the rank of kingdom. There is, however, disagreement over the name criterion: whether heterotrophy or endosymbiontic autotrophy (photosynthesis) is ancestral. Those opting for the latter may prefer Cavalier-Smith's group name: the Chromista. Dick, however, endorses the former interpretation and erects the kingdom Straminipila. What, for him, unites this motley assemblage is the anteriorly directed straminipilous flagellum. More familiarly known as the 'tinsel-type', this form of flagellum bears two rows of tripartite tubular hairs (TTH's) and, vernacularly, a 'straminipile' is any organism forming TTH's, even if it lacks zoospores. In the Straminipilous Fungi Dick treats, in the words of the subtitle, the "Systematics of the Peronosporomycetes Including Accounts of the Marine Straminipilous Protists, the Plasmodiophorids and similar Organisms"; further, "[b]y association, certain non-flagellate fungi , such as some downy mildews; a few uniflagellate fungi [hyphochytrids]; and some biflagellate but non-straminipilous vertebrate gut commensals ... are also included". Many of these fungal organisms (fungi with a small 'f') share a number of traits with the (true) Fungi (chytrids et seq.), most noticeably, osmotrophic nutrition associated with the customary mycelium composed of walled hyphae.
   The monograph is divided into six parts: I. Criteria for diagnoses of flagellate fungi (pp 11-98), ending with a one page discussion of Coevolution; II. Classifications (pp 101-121); III. Myceliar Peronosporomycetes: downy mildews and water moulds (pp 123-169); IV. The lagenidiaceous fungi and similar organisms (pp 171-265); V. Systematics (pp 267-432); VI. Keys (pp 433-474). Seven supplements follow the main text. Two appendices: one giving Lists of bionomials in current use (pp 477-526), the other the Recommended form for taxonomic authorities (pp 527-541); a glossary (pp 543-548); a comprehensive references and bibliography section (pp 551-626); and three indexes (627-670): for topics and major groups of organisms, to genera, and to binomials. The text is interspersed with 33 tables and 24 figures (20 in Part I.). (The Part names head the respective left hand pages while the right hand pages are headed by the respective titles of the major sub-sections in the Parts and several supplements; this useful formatting innovation is a very helpful navigation aid).
   To gain an over-all perspective of this melange that will clue-in the average mycologist, it may be helpful to start with Part VI, which opens with a "Synoptic (non-dichotomous) key to the classes, orders and families of straminipilous and other heterotrophs". Tacitly, the first cut is between the modes of nutrition. The second cut pares away the Labyrinthista with cell walls composed of L-galactose carbohydrate scales (Labyrinthulales and Thraustochytriales) from the rest which have, where known, walls composed mostly of ß-1,3- and ß-1,6- glucans, but sometimes with chitin. The next sorting pulls away species that are unlikely to be straminopilous (e.g., Plasmodiophorales) from the straminopile subphylum Peronosporomycotina. The last named is then partioned between the predominant Peronosporomycetes with biflagellate zoospores and the paltry Hyphochytridiomycetes with anteriorly uniflagellate zoospores (its six small genera are analysed in later keys). The rest of this synopic key sorts out the major taxa of the Peronosporomycetes (subclasses Perosporomycetidae and Saprolegniomycetidae and a number of incertae sedis straminipilous fungi including the third subclass, Rhipidiomycetidae). The documentation and arguments for these taxonomic decisions are presented in extenso in the latter portion of Part II.
   Readers may be wondering at this point: What has happened to the good-old Oomycetes? In the Introduction Dick gives the (checkered) history of the stem 'oomyc-', cites Sparrow's 1976 assertion that the name should be retired, and says now is the time to eliminate non-generic stem names. Accordingly, he has selected Peronospora Corda as the stem name to typify all the higher taxa. He does, however, offer the sop that 'oomycetes' (small 'o') may continue in common parlance for these fungi. The Introduction also includes four tables listing the genera, type species, and the numbers of species, respectively, in the Peronosporomycetes, Hyphochytridiomycetes, Labyrinthista, and Plasmodiophoromycetes.
   Returning to Part I, diagnostic criteria. Of the seven assessed, the foremost are zoospore structure, zoosporogenesis, and sexual reproduction. Zoospore morphology is analysed under seven headings that discuss the definition of a straminipilous zoospore, its various sporangia and motile phases, its variation in shape (bean-shaped, pip-shaped, etc.), types of inclusions (particularly the rare refractile granules whose ultrastructure has yet to be determined), and attributes of its flagella. The first figure has a large general diagram of zoospore morphology and a number of smaller ones showing its various shapes and flagellar insertions; figures that follow present diagrams of zoospore types of particular taxa and specific details of flagellar structure, symmetry, and insertion.
   The characterisation of zoospore formation includes a critical discussion of the considerable diversity of asexual reproduction in these fungi and its three ontogenetic stages (cleavage, vesicle categories, and zoospore taxis); these are followed by descriptions of flagellar retraction, cyst formation (with diagrams of 15 possible final morphologies), and cyst germination. Extrusomes and dense-body vesicles are also reviewed here. Sexual reproduction in these fungi is ordinarily homothallic (automictic). The life cycles are highly variable but basically oogamous and, unlike the Fungi, diplobiontic; i.e., hyphae and zoospores are diploid, meiosis occurs in the gametangia, and the gametes are the only haploid cells. The prodigious variations in oogonia, oogenesis, and oospores and of the whole life cycle are fully described and illustrated.
   The remaining criteria are: nuclear cytology of mitosis (negligible) and meiosis; the assimilative thallus (with a synoptic diagram of divergence and convergence in thallus form); biochemistry (cell wall composition, lysine synthesis, and sterol metabolism); and molecular biology (including the deep molecular divide between the Peronosporomycetidae and the Saprolegniomycetidae).
   In Part II, Classifications, Dick critiques the proposals by Margulis, Cavalier-Smith, and himself for the classification of the lower eukaryotes (Protoctista, Chromista, and Straminipila, respectively). To the arguments presented in the literature, Dick discusses two further factors that have not been particularly considered in the phylogenetic debates: the broad environmental conditions in which major taxa evolve (particularly the marine/freshwater divide) and the importance of heterotrophy and parasitism in this evolution. The second half or so of this Part presents a detailed review of peronosporomycete classifications (see above).
   Part III comprehensively boxes the compass of all that is known about the water moulds and downy mildews.
   Part IV treats systematic problems occasioned by Myzocytium and Lagenidium; the nematophagous 'lagenidiaceous' fungi; genera parasitic on fungi and algae; the Hyphochytridiales and Anisolpidiales; the labyrinthulids, plasmodiophorids, and rozellopsids; and several miscellaneous genera and taxa insertae sedis.
   Part V gives for each taxon ~ kingdom to species ~ its typification, synonyms, literature, and, where appropriate, the key (in the next section), and place in it, where it is identified; also, where required, a validating Latin diagnosis (e.g., Straminipila M.W. Dick, regnum novum).
   In Part VI the synoptic key, discussed above, is followed by a general key that is succeeded by 16 keys to the genera and species of these taxa.
   Dick has devoted a lifetime to studying and interpreting the taxonomy and systematics of the lower fungi. He is to be commended for drawing together a massive amount of historical and contemperary literature and producing such an erudite and authoritative explication of so difficult a group of organisms. By formally establishing the kingdom Straminipila he has ring-fenced this multifarious taxon and made it accessible and comprehensible to students of these organisms. One can but hope that mycologists, phycologists, and protozoologists will take up the challenge. His lucid writing and tightly organized presentation of the taxonomy and systematics of the heterotropic straminopiles is a particular service to mycology. This epic treatise should be in every library with a microbiology (sensu lat.!) collection, but, particularly, in those where students are studying aspects of these fungi.

R. T. Moore

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Mycologist 14 (2000): pp 142-143.

As the preference states, this edition "... represents a continuation of the monographic series begun by J. Lodder and N.J.W. Kreger-van Rij (1st edn., 1952), J. Lodder (2nd edn., 1970) and N.J.W. Kreger-van Rij (3rd edn., 1984). As with each subsequent edition, the number of taxa treated has increased. In the third edition (1984), 60 genera and 500 species were described, here in the fourth edition, there are 100 genera representing over 700 species. Numbers alone do not fully reflect the inceased coverage of the present treatment. Besides newly described species, the current edition includes additional genera of yeastlike taxa, some of which, such as Trichosporonoides and Protheca are not considered to be yeasts, but are included because they are morphologically similar to yeasts and sometimes confused with them. Similarly, we broadened the discussion of the basidiomycetes to acquaint the reader with some of the dimorphic species whose yeast phases are often found on isolation plates. Molecular studies have shown many of these dimorphic species have close phylogenetic relationships with commonly recognzed basidiomycetous yeasts.
   "Not surprisingly, molecular sequence analyses have contributed prominently to the classification used in the fourth ediiton. However, because sequence data are not yet available for all know species, a phylogenetically-based classification system is not fully developed. As a consequence, the placement of many species in genera and families is uncertain. Despite these limitations, the system of classification presented in the current edition is more predictive of natural relaltionships than was possible in earlier treatments."
   Thirty-eight contributors are responsible for the 114 chapters that are divided into 12 Parts: I. Classification of yeasts; II. Importance of yeasts; III. Ultrastructural and molecular properties used for yeast classification; IV. Methods; Va. Classification of the ascomycetous taxa; Vb. Descriptions of teleomorphic ascomycetous genera and species; Vc. Descriptions of anamorphic ascomycetous genera and species; VIa. Classification of the basidiomycetous taxa; VIb. Descriptions of teleomorphic basidiomycetous genera and species; VIb. Descriptions of anamorphic basidiomycetous genera and species; VII. Prototheca a yeastlike alga; VIII. Key to species. These sections are followed by five unnumbered summary chapters: synopsis of species fermentation, assimilation reactions, and other characteristics (915-947), glossary (949-953), references (955-1016), index of taxa by genus and species (1017-1034), index to species and varietal names (1035-1055).
   As this overview indicates, the preparation of this edition was a mammouth undertaking by the editors. Like editors of previous editions they had to ride herd on an assortment of contributors, but, as members of the dynamic contemporary yeast community, they are also fully cognizant and practitioners of the current techniques of molecular and physiological biosystematics that are now central to yeast classification. The resulting timely volume, therefore, has a welcome unity of style, presentation, and content. It provides a crucial bench mark for drawing together a widely dispersed literature; a literature that continues to vigorously expand.
   Several taxa are of potential particular interest to Mycologist readers. In the ascomycetes, Taphrina has not been systematically studied since Mix's monographic studies. The teleomorphs are all highly specialised plant parasites that in culture, and presumably in nature, grow only as single celled, budding yeasts (the anamorph genus Lalaria). On the evidence of different assimiation profiles of anamorph isolates some species may be complexes; e. g., T. betulina and its two morphologically slightly different synonyms T. lapponica and T. turgida and the 16 isolates of T. caerulescens on Quercus that key out to 14 different "taxa". It may be, therefore, that superficially trivial teleomorph variations on different species of oak, if consistent, actually indicate distinct species.
   One of the great merits of this edition is the inclusion and clarification of basidiomycetous yeasts. Twenty-one anamorphic genera are treated. The ballistoconidial Bensingtonia, described by Ingold in the 1986 Transactions for a single species, B. ciliata, now has a total of nine species. The long and troubled history of the type species of Cryptococcus, the familar pink yeast, has been resolved by accepting C. neoformans as the type (teleomorph, Filobasidiella neoformans), The description of a teleomorph, Rhodosporidium, for the also familar and long known red yeast Rhodotorula has done much to clarify this assemblage. Malassezia, familar to medical mycologists, is also now recognized as basidiomycetous. And Trichosporon has been restricted to arthroconidial basidiomycetous species.
   Unlike the endosporic ascomycetes, all basidiomycete teleomorphs, of necessity, are hyphal. A number of these are small and obscure and generally unknown to most mycologists. Of the twenty genera treated, those that may ring a bell include Lindsay Olive's Filobasidium described in Mycologia1968 for a single species, F. floriforme, Sporidiobolus the sexual state of Sporobolomyces and, of the tremelloid genera with yeast phases, Holtermania , Sirobasidium , and Tremella.
   Though obviously not a book that most mycologists and students of fungi would personally purchase, it is a volume that should be in any yeast oriented microbiology laboratory or its institutional library. Yeasts are becoming increasingly important in biotechnology, medical mycology, and environmental studies. Students and investigators in these subject areas should read and become familar with the first four Parts and strive to acquaint themselves with what yeasts are, their importance, and how to identify and recognize those they encounter in their studies.

R. T. Moore

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