Abstract
Fungal plant pathogens alone have the capacity to expend economically consequential amounts of crop
yields and agricultural funding. Domestication of plants not only established plentiful food sources for
human societies, but also provided new nutrient sources for plant pathogens. Host-shifts provide new
evolutionary opportunities for associated parasites to diverge from progenitor populations via rapid coevolutionary
adaptation. A complex of recently diverged and closely related fungal plant pathogens, of
the genus Zymoseptoria, have provided a highly useful model system for studying such co-evolutionary
adaptive processes. The pathogen, Zymoseptoria tritici is of particular interest due to its specialization to
wheat, a globally distributed crop that many societies rely on as a staple. Fungal secreted molecules and
proteins that interact with the host and produce disease are known as effectors and are key to Z. tritici
adaptation. Identification and functional characterization of effectors are essential to understand how Z.
tritici rapidly adapts. In this study, we investigated the in planta phenotypes and population genetic
diversity of two candidate effector genes (Zt09_chr_11_00287 and Zt09_chr_11_00525), identified via
comparative transcriptomics of the Zymoseptoria species complex.
