James Brown denies the fungi are winning

The Triumph of the Fungi: A Rotten History, by Nicholas P. Money (Oxford University Press, 2007, ISBN 0-19-51891-X)

Plants are assailed by an extraordinary range of diseases: blotches and blights, rusts and mildews, rots and wilts. The Triumph of the Fungi romps through the history of research on some of the most deadly ailments caused by fungi and the superficially similar but unrelated water moulds.

The title consciously echoes a classic of popular science writing from 1940, The Advance of the Fungi. The author, E. C. Large, an engineer turned plant pathologist, explained to a non-specialist readership how these microbes cause diseases and how pathologists had learnt about them. In the decades since The Advance was published, new diseases have appeared and spread, huge progress has been made in the science of plant pathology and methods of disease control have improved greatly. 

It might seem that the time is ripe for a new book which tells non-experts about the current state of this subject, so vital for economic production for food and raw materials. Sadly, The Triumph is not that book.

Devastating fungi

Has the advance of the fungi become a triumph? Professor Money seems to think so. He is concerned with the most spectacular and destructive diseases of crops and forests: the rust which devastated coffee in Sri Lanka, potato late blight which brought famine to Ireland, chestnut blight which ravaged forests in eastern North America. Yet these diseases are remarkable precisely because they are exceptional. It is quite mistaken to think that agriculture is on the brink of a fungus-induced calamity.

Not only does The Triumph focus on eye-catching but unrepresentative diseases, but much of it is written in a flippant manner which does not help to explain some unfamiliar and occasionally obscure science. 

Professor Money writes engagingly and informatively about heroes and heroines of plant pathology such as Anton de Bary, who discovered how late blight infects potatoes, and Marie Schwartz, who showed that Dutch elm disease is caused by a microbe. 

At his best, he grips the reader’s interest with accounts of how key discoveries were made and how the science has often become entangled with politics. So it is distracting to find such a passage cut short by a personal anecdote or a frivolous remark. I was left with the strange sensation that Money does not believe his subject will actually hold the reader’s attention unless the scientific pill is heavily coated with humorous sugar.

Frivolity and sensationalism come together at the end of the book, with a spectacular but implausible suggestion that masses of fungal spores caused the extinction of large, flightless dinosaurs (but apparently not the small, feathered ones, the birds). Maybe this just adds another crazy notion to the pile of ideas about the Cretaceous mass extinction, but it will not help to persuade readers that there is serious science elsewhere in the book.

The triumph of the humans

There is an entirely different story to tell about plant diseases, a quieter but more optimistic tale about the triumph of the human mind.

Fungi are indeed permanent threats to farms, forests and gardens. They adapt to new plant varieties, they become insensitive to fungicides and new pathogens arise and spread. Yet by and large, people learn to cope with them and control them. Stem rust caused devastating epidemics on wheat in the USA in the 1950s, but fifty years have passed without comparable damage. Why? 

Because little by little, plant pathologists and plant breeders have made steady improvements in the resistance of wheat to the stem rust fungus. 

Wheat alone provides a catalogue of diseases (powdery mildew, glume blotch, leaf rust are others) which have been reasonably well controlled by patient application of the scientific method in breeding new varieties, developing fungicides and improving crop management. Even the control of potato blight and coffee rust has been improved in this way, though they are still noxious pests when conditions suit them.

The Triumph of the Fungi leaves the reader with the impression that our food, furniture and landscapes, not to mention car tyres, are at the mercy of a barbaric army of microbes. Yet plant pathologists serve the same role in combating these alien forces as Roman soldiers did on Hadrian’s Wall: constant vigilance, skirmishes and sorties, a few hard-fought battles in an unpleasant environment have kept most diseases at bay. The fact that there is little or no news about the vast majority of fungi is the good news about plant pathology.

Professor James Brown is a project leader in pathology of cereal crops at the John Innes Centre, Norwich