Ceratocystis fimbriata modulates effectors during infection for both pre- and post-epidemic isolates

Our goal was to deepen the understanding of the pathogen Ceratocystis fimbriata's biology, which is essential for developing effective resistance strategies in sweetpotatoes. We utilized a recent comprehensive assembly of the sweetpotato C. fimbriata isolate AS236 to identify potential secreted effectors, employing a custom fungal effector annotation pipeline. This process led to the identification of 188 putative effectors.We then conducted extensive RNA sequencing to examine how C. fimbriata adjusts its effector expression within the plant, aiming to identify a subset of effectors active during infection. Our analysis included comparing expression profiles of C. fimbriata isolates from both pre- and post-epidemic periods, revealing distinct patterns of effector co-expression.Our findings were pivotal in suggesting 31 effectors for further functional analysis, based on their differential expression patterns. Among these, we discovered several effectors indicative of a biotrophic phase in C. fimbriata's infection of sweetpotato storage roots. This discovery is particularly significant as it provides new insights into the pathogen's infection mechanisms.The comprehensive catalog of effector proteins we developed is a valuable resource for understanding C. fimbriata's infection strategies. More importantly, it lays the groundwork for effector-assisted breeding in sweetpotato, which could be instrumental in developing resistant crop varieties, potentially mitigating future outbreaks and crop losses..