The first database date on which the address/organization information applied (have a discrete date on which address is known to applied - not necessarily the first date on which the address applied).
Code that uniquely references this record, allowing reference to this record for this version of this database. Better than a primary key, which is automatically generated by a database and not globally unique. VegBank Accession codes are only generated by VegBank, and therefore data integrity can be guaranteed, unlike with a primary key (number).