Comparative genomic analysis of seedless Ponkan (Citrus reticulata)

'Qianyang seedless' (QS) is a widely cultivated Ponkan mandarin cultivar in China, which is a seedless bud sport derived from the seedy Ponkan mandarin. SSR and AFLP analysis suggested that QS shares a very close genetic background with 'Egan NO.1' (EG), a seedy Ponkan mandarin variety. To identify the candidate gene responsible for seedlessness in QS, we assembled the genomes of EG and QS using PacBio long reads combined with Illumina short reads.