Endophytic propagation of Erwinia amylovora in Rosaceae: a proteomic and microscopic approach

Abstract

Erwinia amylovora is the causal agent of the bacterial disease, called fire blight. Fire blight is particularly destructive to most species of the Malaceae and some species in other families of the Rosales. Apple and pear trees are from the economic point of view, the most important host species but also woody ornamentals such as hawthorn, pyracantha and cotoneaster are susceptible to fire blight. The bacterium enters plant tissue via blossoms or wounds, and spreads within intercellular spaces and vascular tissue, killing blossoms, shoots, branches and in the most severe cases entire plants (Vanneste and Eden-Green, 2000) . The severity of the disease results from its destructive character on the one hand and the lack of effective control methods by growers on the other hand. The main objective of this work was to gain a better insight into the infection process of E. amylovora. In chapter 2, we studied the bacterial propagation during flower infections by different microscopic tools. In chapters 3 and 4 we analyzed the proteins involved during the infection process. We also searched for factors that play a role in the virulence degree of different wild type E. amylovora strains.