Obituary: W. A. Hayes

William Alfred Hayes, mushroom scientist: born Llandissilio, Pembrokeshire 13 December 1939; married 1962 Margaret Bone (one son, one daughter); died Solihull, Warwickshire 29 September 1993.

W. A. HAYES was always going to do something special in the world of science. Even as an undergraduate in the late 1950s he showed three qualities that later infused his entire career as a determined and innovative researcher - dedicated to the science and technology of mushrooms. He was extraordinarily quick in grasping central principles behind the diversity of natural phenomena. He was always prepared to question what he was told or what the textbooks said about some aspect of agricultural science. And in the laboratory he had the green-fingered touch that made things work while others were struggling to get 'the right result'.

Fred Hayes was born on a small mixed farm called Penycwm, near Llandissilio, Clynderwen, in Pembrokeshire. He studied dairy science at the University College of Wales, Aberystwyth, before going to King's College, Durham University (later Newcastle upon Tyne University), to read agriculture. After taking a First Class BSc, Hayes began working with Fred Blackburn on fungi that entrap and destroy nematode worms which, in turn, damage potatoes and other crops. In 1964, he gained his PhD for this work, which he hoped might lead to a biological method, not dependent on chemicals, to reduce the agricultural losses caused by nematodes.

It was at this point, however, that Hayes focused on a rather different phenomenon and embarked on the research for which he is now renowned throughout the world. He had become intrigued by the question of what triggers mushroom mycelium - a thread-like form of fungus living below the soil - to produce the above-soil fruitbodies that we recognise as mushrooms.

Joining the Glasshouse Crops Research Institute at Rustington, Littlehampton, Sussex, Hayes began to investigate this process, not only out of biological curiosity but also for good practical reasons: only when fruitbodies are formed are the nutrients in compost converted most efficiently into edible food.

Hayes and his team at Rustington found that pure cultures of mushroom mycelium, in the absence of any other living organisms never produced fruitbodies. They speculated that a bacterium might provide the trigger, but none of the many which they isolated from soil did the trick. So they next worked in the reverse direction, now speculating that some volatile substance(s) produced by mushroom mycelium stimulated the appropriate bacterium to grow. So it proved. When they subjected ordinary soil to these vapours, Pseudomonas putida became the dominant organism. Adding it to cultures of mushroom mycelium immediately triggered the formation of fruitbodies.

It was the discovery of this subtle association that led Hayes into a wide range of related problems concerning the nutrition of mushrooms and composting. During his time at Rustington, from 1964 until 1971, he made many further contributions to our understanding of mushroom nutrition and compost formation, identified groups of microbes playing key roles in composting, and showed how carbohydrates released by some of those organisms served as nutrients for others.

Those years also saw the first international recognition of the practical potential of Hayes's work. In an article in New Scientist in 1969 (highlighted on one of that magazine's first colour covers), he argued that the mass cultivation of mushrooms, a neglected source of high-quality protein, could help to solve problems of malnutrition in developing countries.

This led to inquiries from overseas agencies and private companies and to what eventually became a feverish round of consultancy and research leadership in India, Kenya, Colombia, Thailand, Cyprus, Vietnam and many other countries.

Continuing after he joined the University of Aston, Birmingham, in 1971, and following his move to private consultancy in 1984, these actvities were centred on methods of improving the production of Agaricus bisporus and other mushrooms. Among innumerable projects of this sort, Hayes played a central role in the development of a mushroom-exporting business in Kenya, helped private companies in Colombia to cultivate mushrooms on sugar cane bagasse and coffee waste, and led a team in Himachel Pradesh which has served as the model for the development of a mushroom industry in 18 Indian states. He advised, inter alia, the Food and Agriculture Organisation, the World Bank, the European Economic Community and the Commonwealth Secretariat.

It is hard to understand how, in the midst of his hectic and selfless worldwide travel, Hayes found time not only for his work such as writing (his publications include the monumental Biology and Cultivation of Edible Mushrooms, 1979, edited with ST Chang) and editing (he served on the Editorial Board of the Mushroom Journal and other journals), but also for nonscientific activities. But he did so, not least in relation to the Welsh language (which he had taught, while still an undergraduate, to one of his professors, the plant physiologist Meirion Thomas) and music. Always a enthusiast for the great Welsh choral tradition, Hayes joined the Canoldir Choir in 1977 and sang with them regularly over the years.

Fred Hayes was not simply a scientist of unusual distinction, a pioneer who made genuinely exciting discoveries in a field some formerly believed to be unexciting. He also inspired many others in his quest. And in applying that science he earned the deep respect of his peers, as symbolised in his service as President of the International Society for Mushroom Science from 1986 until his untimely death. Hayes was never interested in research for its own sake; his science was a science that has already fed the world's hungry and will help others to do so in future.