Current red clover breeding research

Authors: Riday, Heathcliffe

Submitted to: International Grasslands Congress
Publication Type: Proceedings
Publication Acceptance Date: 4/14/2023
Publication Date: 5/14/2023
Citation: Riday, H. 2023. Current red clover breeding research. International Grasslands Congress. May 14-19, 2023.

Interpretive Summary: Red clover remains a globally important forage legume grown mostly in humid temperate climates on approximately 4 million ha. In the past 25 years global red clover seed production has stabilized around 10 million kg yr-1, although there is evidence that seed production is increasing globally at around 0.34 million kg yr-1 since the early 2000s. Globally many red clover programs exist targeting specific global regions with a focus on improving plant survival, forage yield, seed yield, and a few other minor traits. Breeding programs are increasing plant longevity by selecting for specific disease resistances, specific agricultural conditions such as mixtures with grass, or specific climate or climate induced conditions such as winter survival or drought. A few programs are targeting forage yield, however, breeding progress for forage yield has been slower. Red clover seed yield improvement is another major breeding target. 1944 to 2017 Oregon U.S. seed production data indicates diploid red clover seed yields are improve at a rate of 7.1% per year. It is, however, unknown what proportion of this increase is due to breeding versus better management. Global red clover breeding efforts tend to be isolated from one another with little exchange of breeding material between global regions.

Technical Abstract: Red clover remains a globally important forage legume grown mostly in humid temperate climates on approximately 4 million ha. In the past 25 years global red clover seed production has stabilized around 10 million kg yr-1, although there is evidence that seed production is increasing globally at around 0.34 million kg yr-1 since the early 2000s. Globally many red clover programs exist targeting specific global regions with a focus on improving persistence, biomass yield, seed yield, and a few other minor traits. Breeding programs are increasing persistence by selecting for specific disease resistances, specific agricultural conditions such as mixtures with grass, or specific climate or climate induced conditions such as winter survival or drought. A few programs are targeting biomass yield per se, however, these efforts are yielding slower selection progress and are often confounded with selection gains for improved persistence. Red clover seed yield improvement is another major breeding target. 1944 to 2017 Oregon U.S. seed production data indicates diploid red clover seed yields are improve at a rate of 7.1% per year. It is, however, unknown what proportion of this increase is due to improved genetics versus improved management. Furthermore, tetraploid red clover which has lower seed yields remains an area of continued breeding interest particularly in Europe. In addition to the major three breeding traits of persistence, biomass yield, and seed yield a few red clover breeding programs are pursuing other traits such as breeding for improved forage quality. Global red clover breeding efforts tend to be isolated from one another with little exchange of elite germplasm between global regions. Programs are often exploring local landraces or local wild/feral germplasm to expand their elite breeding pools.