Completing the peanut genome sequence, and its use in crop improvement using wild species

Summary

We led the international consortium that completed the exceptionally challenging sequencing of the entire peanut genome. Assigned as the “reference genome sequence” it allows the integration of genetic information from research programs all over the world into a unified framework, advancing our knowledge and speeding peanut breeding. At the same time, using this reference and the increasingly sophisticated genetic knowledge that it has generated, we have pursued our long-term research goals of improving the peanut crop using breeding schemes that incorporate pest and disease resistances from wild species.

Situation

Advanced DNA-based genetics enables faster crop improvement. A completed genome sequence is key in this endeavor, serving as a reference framework and allowing genetic data from breeding programs from all over the world can be integrated and leveraged. However, until very recently peanut lacked a complete genome sequence. Peanut is a valuable crop but is plagued by diseases and pests, in the USA the use of chemical control accounts for over 30% of total cost of crop production. Genetic resistance would be the most favorable form of control, but peanut has an exceptionally narrow genetic base and poor sources of resistance to many pests and pathogens. Fortunately, wild peanut species harbor very strong resistances to diseases and pests and adaptation to environmental stresses, which cannot be found in cultivated peanuts.

Response

To construct a common reference for peanut genetics, we led an international consortium that sequenced the peanut genome. Cutting edge technology was needed to resolve peanut’s peculiar doubled genome structure, a result of its hybrid origin in prehistory. This year saw the formal completion of the project, with a publication in the premium scientific journal Nature Genetics. This genome sequence has been recognized as the “reference genome’ and is now being used internationally as a common standard. To ensure practical impact in the field, we continued our long-term work to integrate the pest and disease resistances from wild species into cultivated peanut. We worked with very strong resistances, derived from wild species, to root-knot nematodes, late leaf spot and rust fungi. We developed DNA markers and employed them in special hybridization and breeding schemes to incorporate the resistances into the genetic backgrounds of elite peanut cultivars and breeding lines from the Southeast.

Impact

The sequenced peanut genome provides a framework for research results from all over the world to be directly compared, within a context of more than 66 thousand genes, identified and characterized within their chromosomal context. This is leveraging research in the USA and the world, generating more knowledge and benefits, pure and applied. Our work with wild peanut species has now generated peanut lines that are 95% or more elite peanut genetics, with 5% or less wild species that confers pest and disease resistance. Collaboration with peanut breeding programs in the USA, Brazil, Senegal and Uganda are incorporating these wild species-derived traits into elite local peanut varieties using a combination of traditional breeding and selection using DNA markers. So far, six new varieties have been released in Senegal and one in Brazil, new improved varieties are expected soon in the USA. This will reduce farmer costs, increase yield, reduce fuel use and lower the environmental impact of farming.

State Issue

Plant Production

Details

• Year: 2020
• Geographic Scope: International
• County: Clarke
• Location: College Station, Athens
• Program Areas:
  • Agriculture & Natural Resources