The whole genome sequence resource of Calonectria ilicicola, the casual pathogen of soybean red crown rot

Calonectria ilicicola (ana. Cylindrocladium parasiticum) is a soilborne plant pathogenic fungus with a broad host range, and it can cause red crown rot of soybean and Cylindrocladium black rot of peanut, which has become an emerging threat to crop production worldwide. Limited molecular studies have focused on Calonectria ilicicola and one of the possible difficulties is the lack of genomic resource. This study presents the first high quality and near-completed genome of C. ilicicola using the Oxford Nanopore GridION sequencing platform.

A total of 16 contigs were assembled and the genome of C. ilicicola isolate F018 was estimated to have 11 chromosomes. Currently, the C. ilicicola F018 genome represents the most contiguous assembly, which has the lowest contig number and the highest contig N50 among all Calonectria genome resources. Putative protein-coding sequences and secretory proteins were estimated to be 17,308 and 1,930 in the C. ilicicola F018 genome, respectively; and the prediction was close to other plant pathogenic fungi such as Fusarium species within the Nectriaceae family.

The availability of this high-quality genome resource is expected to facilitate research on fungal biology and genetics of C. ilicicola, and to support the understanding on pathogen virulence and disease management.