ESA Harmonised Resistance Tables (HRT)

ESA Harmonised Resistance Tables (HRT)

Company claims on the level of resistance in a variety to a pathogen are based on tests carried out with well-characterized isolates of the pathogen in controlled environmental conditions. This resistance may be effective against all or some biotypes, pathotypes, races or strains of the pathogen. However, pathogens are known to develop and form new biotypes, pathotypes, races or strains that can cause damage to plants that remain unaffected by the original form of the pathogen.

 To provide the vegetable industry with clear and consistent communication on disease resistance in vegetable crop varieties, ESA’s Working Group on Harmonisation of Resistance Terminology has put together information on the strain/race of a pathogen to which commercial or other varieties are resistant and the level of resistance associated with specific example varieties. These varieties whether it be a commercial variety or a publicly available line or variety are solely provided to illustrate the levels of resistance.

Genetic makeup of the resistance to a given pathogen can differ between varieties and can result in difference in the resistance response within a given level of resistance. Consequently, varieties claiming a same level of resistance for a given pathogen may exhibit a different resistance response.

 This information is available for vegetable crops of the following types/categories – Brassicas/root crops, Cucurbits, large seeded crops, leafy crops and Solanaceae, and is updated regularly


Documents & Publications