A Diversity Fixed Foundation Set (DFFS) represents an informative set of genetically fixed lines representing a structured sampling of diversity across a genepool.
Lettuce diversity set founder lines
Useful genetic variation can be adapted to breed better crops.
Brassica oleracea diversity set founder lines
An allele (short for allelomorph) is a variant of a gene were the DNA sequence differs between two or more variants. Allelic variation describes the presence or number of different allele forms at a particular locus (locus or loci = place) on a chromosome (allelic variation is sometimes used more loosely to describe the overall diversity present). During domestication the number of alleles that are fixed within a crop type is greatly reduced compared to the variation that is left behind in the genepool. Therefore there may be many unadapted useful allelic variants that could be used to improve our domesticated crop types.
VeGIN Diversity sets
At the Warwick Crop Centre we have our own genebank in the form of the Vegetable Genetic Resources Unit (GRU). This GRU has a remit for collection, conservation, characterisation, documentation and research for a range of vegetable crops and their wild relatives.
The genebank holds thousands of accessions representing different crop species. For example, we have over 6000 Brassica accessions. The schematic below highlights how we select a reference sample from the available diversity then fix the diversity in the form of homozygous lines.
Principle behind capturing genetic diversity in the form of Diversity foundation Sets, then fixing the diversity in the form of homozygous lines
The Vegetable Genetic Improvement Network is creating useable genetic resources for Brassica, Lettuce, Carrot and Onion. These are highlighted in the table below.
Fixed genetic resources produced by VeGIN - as of 050411 (B. napus is also part of OREGIN)
These data are to be updated. Many more fixed lines have now been produced.