A characterisation and evaluation (C&E) dataset for a wild/semi-natural perennial ryegrass representative germplasm collection

The aspiration of this programme is to increase the available information on field performance for the considerable range of plant genetic resources held in the Aberystwyth Seed Biobank for the important forage grass, perennial ryegrass. This information will be useful for grassland, environmental and agricultural scientists in developing experimental approaches to understanding performance and resilience and will inform the development of a genetic resources strategy for perennial ryegrass, i.e., for a UK-focused core collection. This information will also be valuable to the commercial plant breeding and forage seed sector through increasing the germplasm options available to them for developing seed products.
The Aberystwyth University Seed Biobank contains c. 3.3k accessions of perennial ryegrass seed in storage, of which c. 50% are wild, semi-natural or traditional cultivars/landraces. The majority of this latter group were actively collected between 1975 and 1995 from sites across the UK and Europe, by sampling pastures and other grasslands many of which are likely now to be no longer in existence in their original forms. This ex situ seed collection is a historical record of perennial ryegrass biology and will contain populations with allele and gene combinations which have not been directly selected for in developing modern, elite, fertiliser-responsive varieties and have never been formally evaluated in field environments relevant to UK agriculture. This is particularly significant as we seek to develop and enhance the capacity of UK grasslands to support livelihoods, a healthy, diverse and nature-rich environment and home-grown food production in the face of uncertain climatic and economic conditions going forward.
In the knowledge that many in situ sources of grassland diversity have now disappeared and that the viability of ex situ seed collections diminishes over time, our programme will screen c. 200 wild/semi-natural perennial ryegrass accessions collected from the UK and Europe. Selection for screening will be made on the basis of seed viability, available seed quantity and geographical diversity. These 200 accessions will then be evaluated over a 3 year period in 1 m2 plots at 5 sites in Wales, encompassing an altitudinal gradient from c. 70-350m above sea level. The plots will be managed using lower fertiliser conditions and scored for above-ground biomass, ground cover, flowering time, disease incidence, rainfall infiltration, chemical composition (as an indicator of associated nutritive value), and invasion by other species.
At the end of the programme, this field-generated phenotype information on individual accessions will be compiled and submitted to the public plant germplasm information resources EURISCO and Genesys PGR, as formal characterisation and evaluation datasets to accompany the existing accession entries.

Our objective is to develop a field-based multi-year phenotype assessment, across a range of UK-relevant environments, of a geographically diverse set of perennial ryegrass wild/semi-natural ex situ accessions. This will inform grassland, environmental and agricultural scientists in developing: 1) experimental approaches to understanding performance and resilience, and 2) a genetic resources strategy for perennial ryegrass, i.e., for a UK-focused core collection. This will also be valuable to the commercial plant breeding and forage seed sector through increasing the germplasm options available for seed product development.
The Aberystwyth University Seed Biobank contains c. 3.3k accessions of perennial ryegrass seed in storage, of which c. 50% are wild, semi-natural or traditional cultivars/landraces (SAMPSTAT 1nn). Of the wild/semi-natural perennial ryegrass accessions, 334 have seed quantities >40 g in medium-term storage. This quantity will allow for both field evaluations and for future seed distribution/multiplication. Following germination tests and categorisation for collection site geographical diversity, 200 wild/semi-natural accessions will be sown at 5 sites across an altitudinal gradient (c. 70m-340m above sea level) in non-replicated 1 m2 plots. The field trials will be continued for 3 years using a low N plot management (50kg N/ha/annum) and individual plots will be evaluated for above-ground biomass, ground cover, flowering time, disease incidence, rainfall infiltration, chemical composition and invasion by other species. Ten modern varieties of perennial ryegrass will be grown alongside the wild/semi-natural accessions at each of the field sites for comparison.
At the end of the programme, the field-generated phenotype data on individual accessions will be compiled and submitted to the plant germplasm information resources EURISCO and Genesys PGR, as formal characterisation and evaluation datasets to accompany the existing accession entries.