Defra holds the National Fruit Collections, which are located at Brogdale, Kent, and curated scientifically by Imperial College, London. These collections constitute valuable genetic resources for projects concerned with the genetic improvement of the UK's principal fruit crops with respect to the requirements of, eg sustainable production and climate change. They contain ~ 545 accessions of pear (Pyrus), as well as collections of apple, cherry, currants and gooseberries (Ribes) and plum. In recent years, DNA markers known as microsatellites have been developed which are proving very useful for 'fingerprinting' accessions. Such fingerprints are invaluable aids to the management of collections, eg when checking for trueness to type after propagation or for detecting likely duplicates.
Building on a successful pilot project to fingerprint the cherry collection, Defra's NFC Advisory Committee recommended fingerprinting the pear collection, which is in the process of being repropagated. This proposal follows that advice, with the aim of fingerprinting half of the collection.
DNA will be extracted from half of the accessions; the extracts will be amplified with a set of ~ twelve microsatellite primers that have already been developed or used at East Malling Research; the amplification products will be separated on an automated sequencer; and the genotypes will be recorded into an Excel spreadsheet that will be provided to the scientific curator at Imperial College.
The fingerprinting will be a great aid to the efficient management of the collections, as has been demonstrated by the cherry pilot project, allowing some of the material to be checked after propagation and some duplicates to be detected. The traditional method of doing this, morphological comparison, is time consuming and could take several years.