Characterization and Utilization of Genetic Resources for Improvement and Management of Grassland Species

Abstract

Characterization and targeted utilisation of genetic diversity are crucial for any successful breeding program and may help to better understand ecological processes in complex multi-species grasslands. Molecular genetic markers allow for a rapid assessment of diversity at the genome level and highly informative, sequence-specific markers have become available for several grassland species. Although many grassland species are outbreeding and therefore require a large number of plants to be analysed per population, technical and statistical developments have enabled the molecular genetic characterisation of diversity for a broad range of purposes. Molecular markers allow for a targeted selection of parental plants in polycross breeding programs, which may lead to improved performance of the resulting progenies. Detailed characterisation of plant genetic resources existing in collections of ecotype populations, landraces or cultivars may enable breeders to specifically complement their breeding material. In addition, the identification and subsequent elimination of duplicate or highly similar accessions helps to reduce costs involved in maintaining large germplasm collections. The analysis of genetic diversity also allows to investigate the influence of management and environment on population structure or to determine the effect of in situ and ex situ conservation on genetic composition at the species or population level. Furthermore, molecular markers may be used to characterise the effect of environmental pollutants on genetic diversity within species present in permanent grassland. For several grassland species including ryegrasses, fescues and clovers, various studies have highlighted the benefit of detailed molecular genetic characterisation for a targeted utilisation of genetic resources.