Field evaluation of grapevines rootstocks inoculated with fungi associated with Petri disease and esca

Abstract

[EN] One year old grapevine rootstock cuttings of 41B Millardet Grasset 140 Ruggeri 161 49 Couderc 1103 Paulsen and 110 Richter were inoculated with pathogens associated with Petri disease and esca of grapevine to determine the effects of fungal infection on percentage of cuttings emerging from dormancy shoot weight and disease severity The cuttings were vacuum inoculated with spore suspensions of either Cadophora luteo olivacea five species of Phaeoacremonium or Phaeomoniella chlamydospora and planted in two field sites in March 2008 Most of the fungal pathogens caused a significant reduction in the percentage of cuttings emerging from dormancy and shoot weight and a significant increase in disease severity in all grapevine rootstocks except 161 49 Couderc Rootstocks 110 Richter and 140 Ruggeri were greatly affected by fungi associated with Petri disease and esca In general Pa chlamydospora and Pm parasiticum caused the greatest reduction in percentage of cuttings emerging from dormancy and shoot weight and the highest increase in disease severity Regression analyses showed a significant correlation between percentage of cuttings emerging from dormancy and disease severity and between shoot weight and disease severity in almost all rootstocks inoculated with Pa chlamydospora