Development of R&D plans for annual legumes

Summary

A comprehensive pre-breeding R & D plan for annual legumes over the period 2013-2017 was developed. A multi-agency, public and private sector team was assembled, led by the Department of Agriculture and Food Western Australia (DAFWA), with collaborating agencies being the South Australian Research and Development Institute (SARDI), New South Wales Department of Primary Industry (NSW DPI) and the Centre for Legumes in Mediterranean Agriculture (CLIMA) from the University of Western Australia (UWA), while private industry interests were represented by Seed Force Pty. Ltd. and Pristine Forage Technologies.

A workshop was held to identify the most important annual legume traits for meat production and the species best able to deliver them. This consisted of an invited panel of 28 industry experts comprised of leading animal specialists, farm consultants, economists, pasture breeders, pre-breeders, agronomists and pathologists and representatives from seed companies with an interest in annual legumes. Discussions were then held with agencies and breeding companies about technologies currently being used and their technical capacity and ability to conduct pre-breeding activities.

This information was used to determine the project activities and the project team to implement them. A response was also sought from the private sector on how they would use the outputs from this project. The workshop recommended the pre-breeding project should focus on traits to increase persistence and autumn-winter biomass production in regenerating stands. This was supported by economic modelling data which showed this would have the biggest positive impact on pasture productivity and profitability. A high legume density early in the growing season leads to greater competitiveness against weeds, resulting in pastures with greater legume dominance and higher feeding value into spring.

The project outcomes:

• The aim of developing new pre-breeding tools and technologies in annual pasture legumes to increase their rate of genetic improvement in plant breeding programs has been achieved. Although the initial beneficiaries of project outputs are pasture breeding programs, graziers will ultimately benefit through the more timely delivery of new pasture legumes with novel traits for increased red meat production.
• The project utilised the plant trait knowledge and practical plant breeding experience of DPIRD and SARDI. The project also built on prior plant cell biology research from UWA into rapid generation turnover of subterranean clover and on genomic studies in subterranean clover and annual medics by UWA and SARDI, respectively.

The following project outputs, as stated in the Research Agreement, were delivered:

• Development of in vitro tools to reduce cultivar development time in subterranean clover;
• Identification of molecular markers for key agro-morphological traits in subterranean clover;
• Identification of diversity for red legged earth mite (RLEM) resistance in subterranean clover, annual medics and other annual legume species;
• Development of RLEM-susceptible gland clover plants to identify genes for resistance;
• Identification of false break tolerance and seed dormancy traits in subterranean clover;
• Identification of diversity for agro-morphological traits within subterranean clover;
• Identification of genes for increased growth at low temperatures in annual medics and subterranean clover;
• Identification of genes for boron tolerance in strand and burr medics; and
• Implementation of an industry engagement and adoption plan.
   
  The following additional outputs have also been delivered:
  • Publication of the genome sequence of subterranean clover;
  • Development of in vitro tools to reduce cultivar development time in annual medics and French serradella;
  • Identification of diversity for salt tolerance in annual medics;
  • Development of a male sterile strand medic; and
  • Identification of false break tolerance and seed dormancy traits in a range of annual legumes.
   

A new plant breeding technique, termed in vitro-assisted single seed descent, was developed for subterranean clover, annual medics and French serradella to increase the number of generations per year, currently restricted to one generation per year.

The new technique allows at least three generations per year, meaning that new pasture legume cultivars can be delivered to farmer's paddocks at least three years earlier. This will allow graziers to capture the benefits of improved pasture genetics much sooner.

The project published the first draft genome sequence of subterranean clover, based on a high-density SNP linkage map, and a subsequent revision to further improve its resolution. This reference sequence will facilitate identification of the genetic basis of agronomically important traits, which are vital for future genetic improvement of the species.