My friend and former colleague Jim Waller, who has died of pulmonary fibrosis aged 86, was a plant pathologist with particular interest in and a profound experience of the diseases affecting tropical crops.
He used this knowledge, as well as his many contacts in agricultural research institutes and UN agencies, to establish a plant pathology liaison unit in 1971 at the Commonwealth Mycological Institute (CMI) in Kew, west London. It was then part of the Commonwealth Agricultural Bureaux, funded by the Foreign Office’s overseas development administration, to assist developing countries with the identification and management of crop diseases.
The unit soon became an essential stopover for many international scientists involved in agricultural development, enabling the CMI to cement its reputation as a centre of excellence in plant-disease diagnostics with its unique blend of mycologists and pathologists, and world-famous fungal herbarium and culture collection.
Improving food security for smallholder farmers throughout the tropics became a main focus, while the unit also played a key role in unravelling plant diseases such as Sumatra disease of cloves and coffee berry disease.
Born in Swavesey, Cambridgeshire, to John Waller, a shopkeeper, and his wife May (nee Foster), Jim was rooted in the countryside of the Fens. He went to Cambridge high school for boys and won a scholarship to Magdalene College, Cambridge, in 1957, but first had to undertake national service in the Royal Army Medical Corps, attached to the 48th Gurkha Infantry Brigade in Hong Kong, where he shared a barrack with the actor Oliver Reed: it was a deeply formative experience, according to Jim.
He graduated from Cambridge with a degree in botany in 1962 and, a year later, with a diploma in agricultural science. This was followed in 1964 by a diploma in plant pathology from Imperial College London and, much later, he was awarded a PhD from Cambridge based on his published work.
In 1964, he joined the overseas development ministry (ODM) and was posted to the newly independent Kenya, where he worked for the ministry of agriculture in Nairobi on diseases of arable crops. From 1967 to 1971, he was a plant pathologist with ODM at Rothamsted Experimental Station, but spent the greater part of that time on secondment to the Coffee Research Institute in Ruiru, north-east of Nairobi, where he developed his interest in coffee and its diseases.
After official retirement in 2000, Jim continued to undertake consultancies and mentor students and staff. He was an enthusiastic allotment holder, a keen fisherman and more than competent on the alto saxophone, playing in a local jazz band.
His wife, Rosemary (nee Ison), a nurse, whom he met in Cambridge, predeceased him. He is survived by their children, Jackie, Sarah and Martin, and eight grandchildren.
