Resistance of varieties to pests: The ISF DRT group in action
The Disease Resistance Terminology (DRT) group of the International Seed Federation (ISF), chaired by Valérie Grimault, the director of the GEVES Pathology Laboratory, met in Washington DC on 9-19 April 2019. The meeting was hosted by ASTA (American Seed Trade Association).
This working group brings together representatives of international seed companies, examination offices (France, Spain, Netherlands) and networks of reference material (CPPSI in the USA, Plantum in the Netherlands, MATREF in France). Its purpose is to promote the harmonised use of terminology related to pest resistance. Its actions include coding pathogens for which resistance has been declared, harmonising terminology, publishing differential host sets, and developing procedures to validate and name new races of pathogen.
The guide for naming new races has been finalised and a communication campaign has been prepared for poster presentations at congresses. Some of them will be presented by Sophie Perrot, the head of Varietal Resistance at GEVES, at the next Eucarpia Pepper and Eggplant congress which takes place next September in Avignon (France).
The bioagressor codes and differential host tables have been revised.
In order to improve coding of races of pathogen, international projects are in process in the form of a ring test:
- Passalora fulva / tomato – to define a new set of differential hosts and a new race coding system, coordinated by Naktuinbouw
- Fusarium / lettuce – to validate race 4 and define a new set of differential hosts, coordinated by GEVES
- Oidium / melon – to define a new set of differential hosts and a new race coding system, coordinated by GEVES
All of these actions will allow for better harmonisation and reliability in variety resistance testing at international level.