Library selection was based on randomly fragmented genomic DNA. High-quality genomic DNA was randomly fragmented to 300-350 bp by ultrasonication. Sequencing libraries were prepared through end repair, 3-prime adenylation, adaptor ligation, fragment purification, and PCR amplification. The effective concentration of each library was quantified by quantitative PCR. Libraries that passed quality control were sequenced on the DNBSEQ-T7 platform in paired-end 150-bp mode.