Objective 5 - Simon Griffiths (JIC)

AE Watkins and Gediflux Germplasm Collections

The support of WGIN 1 for the AE Watkins Collection and the Gediflux Collection opened up community use of these resources which, together, provide a unique description of world wheat germplasm changes over the past 90 years. As already described, extensive phenotypic data for both collections have been collected and made available on the WGIN website. JIC has a purpose built medium term seed storage facility and will continue to maintain and distribute this material. We now intend to put in place resources that will help us and others to exploit this resource more efficiently. We propose:

DArT Genotyping of Gediflux and AE Watkins Collections

The low data point cost of DArT means that high density genotyping of large wheat germplasm collections is possible. This will allow the lines to be grouped according to genotypic similarity. Representative lines from each grouping can then be used to develop a core set of lines which would be the first port of call for allele mining and phenotyping studies and allow the informed selection of polymorphic parents for Activity 8, 10 and populations developed within this Activity. The genotypic data would also complement the phenotypic data already collected under WGIN 1 and the proposed phenotyping work of JIC, RRes and Nottingham for WGIN.

More extensive allele mining

The AE Watkins and Gediflux collections are already in a suitable state for allele mining since large quantities of seed and high quality extracted DNA is available. Generic (A, B, and D genome amplified) or genome specific assays will be used to amplify all alleles of genes of known function. Variants will be resolved by sequencing or an alternative SNP detection platform. . This type of study has already been carried out within WGIN 1 for Vrn-A1, Vrn-D1, and Vrn-B1 and outside of WGIN for Ppd-D1. Here we propose to continue this approach as the identification of genes involved in sustainability traits such as yield stability, resource use efficiency, and drought tolerance emerges from the literature. Existing candidate genes controlling these complex traits are limited. At this stage the identification of alleles for glutamine synthase a critical gene in the nitrogen assimilation pathway is the most appropriate candidate for this approach. If new alleles are identified that are likely to change the function of the gene then the allele will feed into the NIL programme so that the effect of the allele can be assessed in a context relevant to UK agriculture.

Population development

A small number of AE Watkins lines selected by WGIN partners will be selected on the basis of our phenotypic screens and used to develop up to ten single seed descent or doubled haploid populations of 94 lines. The second parent will be Paragon. Populations will be genotyped with DArT and phenotyped at JIC. The aim of this work is identify useful novel genes and alleles that are not currently used in the UK wheat breeding pool.