Extracting New and Useful Alleles from Wheat Landrace Cultivars of the AE Watkins Collection

The Watkins collection is a rich repository of genetic diversity with potential value for wheat breeding. In the UKs Wheat Improvement Strategic Programme (WISP) we have established a pre breeding pipeline for the exploitation of this variation. Landrace accessions have been multiplied from single seeds of 1050 cultivars and subjected to high density genotyping to reveal nine ancestral groups which we then sampled to form a Watkins core set of 120 lines. Each line of the entire core set was crossed with one UK spring wheat variety, Paragon, to produce a nested association mapping population of over 10,000 F4 recombinant inbred lines, all of which have been genotyped and used to construct unique consensus genetic maps, which reveal more of the surprising variability of genome organisation in wheat. Multi site field experimentation at contrasting fertiliser regimes, dissecting biomass, yield, and N partitioning, have identified over 1000 QTL in these populations. From these, 150 Watkins alleles of potential value for breeding have been introgressed into Paragon by a process of marker assisted backcrossing producing Near Isogenic Lines (NILs) accompanied by Axiom 35K genotyping. Where the NILs confirm the beneficial effect of the Watkins allele they enter multisite commercial yield trialling as part of the WISP Breeders Diversity Toolkit (BTK) together with a set of single nucleotide KASP markers for marker assisted breeding. All of the resources described are available upon request and visible via the WISP website. The future direction of the landrace BTK and its potential impact will be discussed.