High-Quality Genome Assembly and Annotation Resource of Three Botryosphaeria Pathogens Causing Chinese Hickory Canker.

Abstract

Tree trunk canker is the most critical disease threatening the Chinese hickory (Carya cathayensis). Except for the well-known pathogen Botryosphaeria dothidea, our group has previously reported three new pathogenic species, including B. corticis, B. fabicerciana, and B. qingyuanensis. Here, we reported almost chromosome-scale genome assemblies of the representative strains of these Botryosphaeria species using the Oxford Nanopore Technologies (ONT) sequencing platform. The assemblies were 44 to 46 Mb in size, and contained less than 14 contigs (13 - 14) with the contig N50 of around 4 Mb. The BUSCO completeness of genome assemblies was around 99% at the Ascomycota level. These genome assemblies contained no more than 8% repeats and around 13,000 (12,876 - 13,677) protein-coding genes. Gene functional annotations, including pathogen-host interaction, carbohydrate active enzymes (CAZymes), cytochrome P450 enzymes (CYPs), putative secreted proteins, and secondary metabolite biosynthesis gene clusters (SMBGCs) were performed. Comparative genomics analysis shows that these stains shared 11,489 core orthologous gene clusters with our previously reported B. dothidea strain BDLA16-7. The almost chromosomal-level and well-annotated genome assemblies will provide valuable comparative genomic resources for Botryosphaeria species.