Influence of stress treatments on the infection risk for Botrytis cinerea on apple

Abstract: In Europe the pome fruit growing industry is currently confronted with residuerestrictions imposed by marketing chains as retail companies and import countries. Next to a highquality product also a limited residue loading on the fruit surface is requested. Mostly thechemical fungicides applied shortly before harvest towards fruit rot decay during storage arefocused as they are frequently detected after analytical analysis. The past years researchconcerning alternative approaches has exploded. In line of this topic, an IWT-project(IWT070573): “Engineering of the antioxidant metabolism in apple fruits for a less sensibility ofstorage diseases and a higher nutritional value” has started. During this project the relationshipbetween different cultivars, pre- and post-harvest stress treatments, harvest time, antioxidantmetabolism and the resistance against pathogen infections in function of the storage time will beinvestigated. Until now the effect of some cultural and physical measurements on thesusceptibility of different cultivars for Botrytis cinerea was evaluated. The results show that thereis a clear difference in susceptibility to B. cinerea between different cultivars: Braeburn and Fujiare the most susceptible. The effects of the different pre-harvest stress treatments differ betweenthe cultivars. Furthermore the B. cinerea infection progressed more rapidly on the shadow-side ofthe fruits compared to the sun-side. The results from this project can lead to an alternativeapproach for the chemical disease management of Botrytis cinerea in the field.