NP0d
All ovules were hand-dissected under a stereomicroscope and frozen immediately in liquid nitrogen.RNA was extracted by the RNeasy MiNi Kit (50) (QIAGEN). The quality of the RNA was evaluated buy gel and the Agilent 2100. A total of 1 g RNA per sample was used for library preparation with NEBNext Ultra RNA Library Prep Kit for Illumina and sequencing with Illumina HiSeq2500.