Host Recognition and Specific Infection of Endomelanconiopsis endophytica during Early Infection

Coevolution between the pathogen and host plant drives pathogenic effector diversity. However, the molecular mechanism behind host-specific pathogenesis remains to be explored. Here, we present a 43 Mb whole-genome sequence ofEndomelanconiopsis endophyticastrain LS29, a host-specific pathogen of the common subtropical treeCastanopsis fissa. We described its genome annotations and identified its effector candidates. By performing temporal transcriptome sequencing ofE. endophyticaonC. fissaduring early infection, we found thatE. endophyticarepressed other microbes in order to attack the tissue of the host by producing antibiotics earlier than 24 h post-inoculation (hpi). Simultaneously, a variety of effectors were secreted to recognize the host plant, but most of them showed a significantly opposing expression regulation trend after 24 hpi, indicating that 24 hpi represents a key time point between host recognition and specific infection. Furthermore, a comparison of isoenzymes showed that only a few effectors were identified as specific effectors, which were involved in hydrolyzing the compounds of the plant cell wall and releasing fatty acids during the early infection ofC. fissa. Our results determined host recognition timing and identified a specific catalog of effectors, which are crucial for revealing the molecular mechanism of host-specific pathogenesis.Keywords:comparative transcriptomics;effector;genomics;specific infection;whole-genome sequence