library_construction_protocol: The DNA extraction was performed following the manufacturer instructions using the Quick-DNA Plant/Seed Miniprep Kit from Zymoresearch. For each sample the DNA concentration and quality was measured using a Qubit fluorometer. Ultralow Methyl-Seq System (Tecan/NuGEN, Redwood City, CA) has been used for library preparation following the manufacturer's instructions. DNA samples were quantified with Qubit 2.0 Fluorometer (Invitrogen, Carlsbad, CA). Final libraries were checked with both Qubit 2.0 Fluorometer (Invitrogen, Carlsbad, CA) and Agilent Bioanalyzer DNA assay (Agilent technologies, Santa Clara, CA). Libraries were then prepared for sequencing and sequenced on paired-end 150 bp mode on NovaSeq6000 (Illumina, San Diego, CA).