In Memoriam: Dr. Cees P. de Jager

Published on
March 10, 2022

January 5, 2022 Dr. Cees P. de Jager passed away in Bennekom at the age of 87.

He was born May 23, 1934, in Diever and got his High School (HBS-B) diploma in 1952 in Utrecht. After a number of years in various administrative jobs he entered the ‘Landbouwhogeschool’ in Wageningen in 1961 and studied Horticulture, with Virology as a minor, finishing in 1968. Soon thereafter he joined the Virology laboratory when it was in a build-up phase and housed at the wooden barracks west of the former Phytopathology and Nematology buildings. He was particularly interested in the genetics of plant viruses with multipartite genomes, such as cowpea mosaic virus. April 1978 he defended successfully his thesis entitled: Genetic analysis of cowpea mosaic virus mutants, with the former head of the Laboratory of Virology, Professor Jan van der Want (1921-2007), as promotor. Cees was finally trained as a classical plant virus geneticist at the dawn of the molecular era well before reverse genetics made such studies a lot easier.

After his PhD defence Cees continued his research, but at a slower pace as he did a lot of teaching, lecturing and organized practicals. As a researcher Cees was very meticulous by repeating in vivo recombination experiments many, many times to be sure of the outcome. Janneke Saaijer-Riep was his technician and they formed a perfect research and education team. Cees published not too many papers, but they were invariable succinct, well-designed and fine examples of classical plant virus genetics. He also mentored and supervised a few MSc students, such as Kees van der Beek, who later became a successful PhD student himself. During the later years Cees practiced the use of a detailed time sheet to make sure he spent his time well and did not lounge around. But above all, Cees was an excellent teacher.

In the mid 1990s when the wooden Virology barracks were turned in for a brand-new building Cees took early retirement. However he remained professionally active and published, together with Dr. Jeanne Dijkstra, a laboratory manual on plant virology concepts and techniques entitled Practical Plant Virology, J. Dijkstra and C.P. de Jager, 1998, 459pp. This manual was very well read, cited and frequently downloaded up to the present day. It was specifically useful in developing countries for its practical approaches but also reflected the state of the art in practical plant virology at the time.

On a personal note, Cees was a pleasant colleague and invariably smiling on external observations and inside fun. He was always positively tuned and enjoyed the company of colleagues and students. He was always present on the Annual Virology Picture, now on display at the Virology corridor of the Radix building. At home he was the ‘handy man’, assisting his wife Nelleke in renovating their home in Wageningen Hoog and in gardening and foresting. They both made many cultural trips overseas until Nelleke, who was a former beadle at our university, died in 2013. Cees is survived by daughter Annemiek and son Wouter and three grandchildren. Memorial services were organized January 13 2022 with corona-style attendance.  

Cees was part of the team that laid the foundations for what the laboratory of Virology is today. 

Just M. Vlak

March 9, 2022