The role of the outer integument in Annona
Total RNA was extracted from pollinated pistils containing early seeds (PS) and pistils without early seeds (P) of Annona ino and wild-type Annona, combining the CTAB DNA extraction protocol (Doyle and Doyle, 1987) and the Qiagen RNeasy Plant Mini kit (Qiagen). The P samples were obtained by removing early-developing seeds from the pistils of young fruits through microdissection with a microscalpel under a stereomicroscope. For each genotype, RNA was extracted from both PS and P samples obtained from three individual fruits at 4 and 8 days after pollination (DAP).