A fungal thread of death


Harry Marshall Ward and the fungal thread of death
By Peter G. Ayres . APS Press , The American Phytopathological Society, St Paul, MN, USA , 2005 . Hardback , vii + 168 pages . ISBN 0-89054-333-X , $79

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This biography describes a man who made many key contributions to plant pathology and to a lesser extent diverse aspects of botany, mycology and bacteriology. This was achieved at a time when sciences were developing from observational to experimental and the foundations of scientific education and research were being laid. Harry Marshall Ward (HMW) maintained a precarious balance between his professional and private lives, and his eventual extensive commitments, in the view of the author, ‘helped to kill him’.

The book comprises eight chapters spanning the life of HMW from 1854 to 1906. The chapters are successfully interwoven rather than in strict chronological order. Each is a detailed account of his achievements, strengths and weaknesses, but especially of the people, attitudes and events that influenced him or were influenced by him. Each chapter benefits from some charming illustrations of documents, HMW's Victorian contemporaries and peers (usually bearded or moustachioed), his dwellings and laboratories. The biography has required very extensive research by the author and is well referenced, based on such diverse sources as journal papers and many family letters. Also provided is a fascinating list of Harry's publications. Most (74) are single author, as that was the practice then rather than joint authorship (a mere eight); he was also the author of 11 books. Latterly he favoured Annals of Botany, which he helped to set up in 1887, and Transactions of the British Mycological Society when he was President or Vice President from 1900 to 1906 of the British Mycological Society. The journal Nature was not so prestigious then, and one of his papers in it was called merely ‘Roots’.

Peter Ayres’ Prologue, which I have extended, would serve well here as a summary of his subject's early years. HMW eventually became a Fellow of the Royal Society and Professor of Botany at Cambridge. He overcame the class boundaries, which demarcated mid-Victorian Britain, by his intellect and exceptional capacity to work with passion and direction. His lack of financial support was countered eventually by the nation realizing that, for continued prosperity, school teachers were needed to teach science; he won a coveted place at South Kensington, London. His enquiring mind drove him further, however, and he wished to take a degree and to research biology. A rich friend of similar age financed his studies and he obtained a first from Cambridge. His subsequent career encompassed working on the devastating coffee rust in Ceylon (Sri Lanka); a Fellowship leading to assistant lecturer at Owens College in Manchester (the present site of University of Manchester), when he published ‘The sexuality of fungi’ and the less arresting ‘An aquatic Myxomycete’; the Chair of Botany in 1885 within the Forestry Branch of the Royal Indian Engineering College, where he published on ‘The oak’ and ‘Timber and some of its diseases’; the chair of Botany at Cambridge in 1895.

Harry devoted himself to ‘The Cause’– the establishment of a vigorous botanical school in Britain. This was partly inspired by the changing attitudes in French and German universities, which were eventually surpassed as politics in Germany stifled intellectual progress.

His achievements are at first sight confusing as he worked on many things and, as the author makes clear, at times lost direction. He realized that there was a need for links between science and industry and provided some input to the brewing industry in its early years. By 1898 he had contributed several papers for brewers’ journals, including ‘The fungi of fermenting vessels, vats etc’. He analysed the elusive ‘Ginger Beer Plant’ in terms of the microbial components of the inoculum that are essential to that fine beverage – a microbiologist's nightmare, according to Ayres, and HMW admitted as much. He became involved in analysis of drinking water in these times of cholera and unscrupulous water companies, in particular investigating the survival of bacteria, as exemplified by Bacillus anthracis, and the bactericidal effects of sunlight; but this was an unfortunate choice as B. anthracis is a soil-borne organism. Also, he did not employ statistics ‘without attempting to lay stress on actual numbers’. He described hyphal tip extension and surmised that a ‘ferment’ substance at the apex keeps the cellulose in a soft extensible condition and the pressure from behind drives the tip forward. He also described fungal dimorphism.

His work was too diverse to put him amongst the world's great scientists, but Ayres argues that his major contributions are to physiological plant pathology. His painstaking microscopy showed the route of infection by rust fungi and he countered a proposed more mystical route that reflected the ignorance of those times. He was perhaps the first to describe the hypersensitive response (without naming it as such) and to lay the foundations for susceptibility and immunity in plants; in this context he was an important collaborator with Biffen, whose successful wheat breeding for disease resistance is legend. He was in error, however, in concluding that cereal rusts could swap hosts, this being disproved later by Stakman in 1913. Ayres points out that conditions for experimentation were difficult then, with, for example, inevitable cross-contamination of isolates under the basic conditions for plant growth.

Enzymes were not known as entities, but HMW realized, from study of a lily disease, that plant cell walls were dissolved by some extracellular ‘ferment’ that had solvent action on ‘cellulose’. However, this followed De Bary's work on wall dissolution by Sclerotinia acting on carrot roots so was not entirely original. More significant was the demonstration by HMW of production in liquid culture of a tissue macerating factor, which he found was heat labile and could be precipitated with alcohol in an active form. HMW realized that evidence pointed to the existence of fungal enzymes or toxins and host antitoxins as decisive factors in infection or immunity, ‘although I have as yet failed to isolate any such bodies’.

There were no direct links, but those who benefited from HMW's legacy included William Brown, who developed an assay for ‘cytase’, later pectinase. Brown became the first professor of plant pathology at Imperial College, South Kensington in 1928. His PhD student was R. K. S. Wood, and, to bring the connections up to date, I was one of Wood's many graduate students, working of course on pectinases. Wood trained around 50 PhD students and produced the monograph Physiological plant pathology, the bible for the exciting pre-molecular era of pathology research, spanning the 1970s and early 1980s. By contrast, HMW tended to work alone and did not have a string of postgraduates or visiting researchers passing through his laboratory – one virtue he did not bring back from visiting Anton DeBary.

This book is written with obvious enthusiasm and provides remarkable detail. Much of the text goes well beyond the life of HMW as many others get extensive coverage (some of them too much in my view), such as in Chapter 3, which largely considers HMW's hero, Anton DeBary. At that time German botany was leading the way and Harry made visits to DeBary in Strasbourg and Sachs in Wurtzburg. Personalities aside, I predict that most scientifically minded readers will be intrigued by the descriptions of the inadequacy of education in Britain and the way science was taught in universities. Textbooks went unchallenged and hypotheses were largely untested. Key appointments often reflected connections and influence. Harry's enthusiasm and abilities clearly had an impact on this stasis. How many of us researching biology under modern conditions are aware of the hurdles then that had to be overcome? Technology has moved on too, of course; Harry's communications from Ceylon took 3 months to reach the UK. However, he did not have to put up with junk emails. Yet we might envy the enthusiasm of the public and schoolteachers for the British Association for the Advancement of Science meetings in those days. HMW used these as one way of becoming integrated into the scientific establishment and became deeply involved in its organization. The 1887 meeting in Manchester attracted no less than 3838 delegates.

We have moved on in other ways, too, in terms of the ability to write in accepted styles and to a given length. Ayres states ‘Harry's writing was never succinct’. Thus, in five reports on water bacteriology published in the Proceedings of the Royal Society, HMW was responsible for 504 pages of text and figures; even then, that verbosity was disapproved of by some of his peers. Likewise, his Presidential Address in Toronto to the botany section of the British Association was not exactly brief, at almost three times longer than that of any other President. Ayres notes ‘If the spoken version matched the written (28 pages) it would have filled most of the time between its start at 11.30 and the next timetabled talk at 2.00 pm’.

I have to question who would constitute the readership of this biography, impressive as it is. The modern molecular generation of plant pathologists are likely to pass it by, as microscopy and life cycles are not in vogue. The lay public are unlikely to be held by the dense detail or to be interested in the contributions of this man, which do not seem so significant in the modern day context. Ayres has endeavoured to explain certain basic concepts such as fermentation, life cycles, plant walls and enzymes, but I am not sure who these will help as they are pitched at different levels. That leaves an ever-decreasing group of traditionally trained pathologists (botanists and microbiologists) along with historians of science and education.

I wish the author had added a personal touch to explain why he evidently dedicated so much time to the biography of this man. The answers are implicit in the text, but what was the trigger? Was Ayres a fan from the outset, or did he, like me, come to realize much later the importance of such pioneers? Also, the author, a respected physiological pathologist, deserves a few notes on who he is and what he has achieved. APS should not assume that everyone will know.

At the very least, the book is a key addition to any scientific library. The history of science and dedicated pioneers such as Harry Marshall Ward should not be forgotten; it provides context for those of us still building on these early discoveries and should make us more content with our lot, still imperfect though it may be.