Black rot is the most important disease for Brassica crops globally, caused by the bacterium Xanthomonas. This project aims to identify key plant processes which are hijacked by the pathogen leading to susceptibility. Loss of such susceptibility factors promotes resistance against pathogenic infections. Overall, this project will provide genetic leads for breeding natural resistance against black rot helping to reduce chemical disease treatments and potentially benefiting agriculture worldwide.

The aim of this project is to obtain breeding leads for black rot disease in Brassica by identifying and
characterizing host processes that are manipulated by Xanthomonas pathogens

Within the MMIP ST2. Biotechnology and Breeding, this multi-facetted project focuses on the following
outcomes:
• Plant diseases caused by the genus Xanthomonas are a major problem in agriculture (e.g. tomato, sweet
pepper, banana, citrus, cassava, rice, lettuce, and brassicas). This project address major knowledge gaps
and will provide molecular understanding of the infection process and identifies plant weaknesses. Why
do these bacteria cause systemic vascular disease after entering the host via hydathodes (water pores)?
By systematically studying the function of bacterial effector proteins (key virulence factors) in the model
plant Arabidopsis thaliana (thale cress), we can identify new leads for a targeted breeding strategy in
crops.
• Our strategy to identify core effector proteins of the pathogen that significantly contribute to virulence is
the first step to gain insight into the plant's genetic and physiological weaknesses and thus offers the
opportunity to generate increased resistance in cabbage and possibly other crops, such as rice, based on
our approach (crossover with MMIP A2).
• Our established phenotyping facility allows robust tracking of disease symptoms and bacterial spread in
the host over time, and importantly, during different infection stages. This gives us a quantitative
measurement methods, which we can apply for reliable disease screening of genetic sources for
resistance traits (crossover with MMIP A2).
• Our proposed translational genomics project includes the development of new proteomic and
transcriptomic methods to identify plant proteins and plant processes, respectively, that represent
susceptibility factors for the black rot pathogen. Moreover, we incorporate our identification methods
directly in Brassica crops and use gene editing as proof-of-principle for resistance, which needs to be
introduced in lead cultivars by traditional, non-GMO breeding methods. Creating disease resilient Brassica
crops will eventually lead to a reduction in the use of copper-containing pesticides (crossover with MMIP
A1, A2, D2)