design: The genomic DNA were extracted according to the phenol-mimicking method.All qualified DNA samples were standardized to 20 ng/L, then a total of 20 L restriction endonuclease mixture (EcoR I + Pst I) was added, and incubated at 37 C and 65 C to produce small DNA fragments were purified after digestion using magnetic beads to remove impurities. Sticky ends of fragments were ligated with custom-designed adapters, and ligation products were size selected (400600 bp size range) in agarose.  These selected fragments were further amplified using PCR. Finally, we removed residual primers and purified PCR libraries using magnetic beads, and library sequencing was conducted on the Illumina Xplus platform according to the standard operation procedure. The sequencing mode was PE 150.