Obituary for Prof. Don Griffith †

It is with great sadness that I have to report the death of a great and innovative acarologist, Donald Alister Griffiths. Don died at the age of 91 on 6th July 2018 after a short illness.

Don was born on 2 July 1927 in Pontypridd, Wales, one of a fraternal twin.   After his army service in Germany (1945-1948), he worked towards and received his BSc in 1951, in Aberystwyth, Wales.  Don married Mercia in 1953 and she went with him for his Masters. Don was awarded a Kellogg Fellowship to do his MSc at the University of Minnesota, St Paul under Clyde Christensen, and received the degree in 1958.  Don and Mercia then returned to the UK where their first son Edmund was born in 1959, and their second son Huw in 1961. Don worked on his PhD at the Royal Free Hospital, University of London under Mrs. Hughes from 1961-1964. 

Don's career was largely spent at the Pest Infestation Control Laboratory, Slough, England, where he studied mites of post-harvested foods. In the 1980s he became Head of the laboratory with responsibility for around 80 people. It was there that he developed techniques which were later used for off-plant mass rearing of various mite species, for use in mass production of biocontrol agents used in greenhouse pest control.

Probably his most significant innovation, which is now the industry standard, was the invention of the Controlled Release System of sachets for Amblyseius cucumeris during the early 1990s. He had set up production of this mite at Bunting Biological Control during the 1980s and quickly realised that applying loose mites in bran onto plants infested with the newly arrived pest Frankliniella occidentalis was not sufficient to gain control. Don was solely responsible for the idea of using a breeding colony of mites to give continuous long-term release. The first tests were in polystyrene vials with twist ties to hold them in place on the plant, but this rapidly evolved into the paper sachet design we know now. Don also led the first work looking at emergence of mites from sachets, and improvements to performance from changes in paper type. This was such a novel and inventive concept, that the idea was rapidly taken up by other mite producers and has for years been a dominant method of pest control in commercial vegetable and flower crops, now extended to many other Phytoseiid mite species.

Another of Don's major research successes was to unravel the taxonomic significance of the morphological variation reported in the stored cereal pest Acarus siro. The bulk of Don's other publications concerned Astigmata, but his broad acarological expertise enabled him to also publish on the Eriophyidae and mestostigmatid pests of bees. 

Don was interested in the use of bumblebees and their mass production for greenhouse pollination.  In 1989 he worked with Dr. Richard GreatRex as Don was starting bumblebee production for Bunting Biological Control and Brinkman – later to be Bunting Brinkman Bees.  He visited Australia a number of times.  In 1999 he toured Australian greenhouses with other IPM experts and subsequently in the same year visited trial sites in Spain where Novartis was releasing the Australian predatory mite Amblyseius montdorensis. Don returned to Australia to work with Drs. Stephen Goodwin and Marilyn Steiner, trying to make a case for Bombus terrestris to be introduced into mainland Australia in the late 1990s early 2000s. He visited Australia for the last time in 2007. In later years he travelled often to Spain as a consultant for Agro-Bio.

His first wife died in 2003 and he remarried in 2006 to his present wife, Zofia, a stored products mycologist who also worked at the Pest Infestation Laboratory from 1969-1987. Far from slowing down after retiring, Don had a subsequent career in phytoseiids and biocontrol, and this family was the subject of his last paper, published only in 2015, entitled The 'Californicus' Conundrum. He had a particular and long-term interest in the taxonomic history of the phytoseiid mite Amblyseius californicus, and pursued it with his usual passion and thoroughness. Don had a low tolerance for poor science and was not afraid to express his views!

Don was one of the founders of the sadly now defunct acarology course held at the University of Nottingham, England. During the approximately 25 years the course ran, he was an entertaining and generous teacher, and his lectures hold fond memories for so many of us who attended the course.

Don is survived by his twin sister, Pauline, his wife and two sons. His knowledge was second to none, and he will be sorely missed by all.

Phyllis G. Weintraub