WP2: Genetic improvement and small plot evaluation of forage production and utilisation of novel legume/grass mixture [Germinal].
In NUE-Leg, Germinal Horizon is responsible for developing new pre-commercial breeding lines into farm-suitable legume varieties. We will cover three core species, including hybrid clovers, red clovers, and lotus.
DoubleRoot – hybrid clovers
Caucasian clover (Trifolium ambiguum) is highly tolerant of biotic and abiotic stress, including grazing pressure, heat, drought and periods of extreme cold, partially due to its rhizomatous growth habit. Previously, it hasn’t been used by UK grassland farmers due to its slow establishment and low forage yield.
However, the benefits of Caucasian clover can now be realised in grassland farming following the development of DoubleRoot hybrid clovers by IBERS and Germinal Horizon. As a world-first cross of Caucasian and white clover (Trifolium repens), DoubleRoot combines the best of both to deliver resilience and agronomic performance.
This gives DoubleRoot superior persistency, as evidenced by its ability to withstand extreme temperatures of -30°C up to +30°C and survive climate conditions that conventional clovers can’t. All while fixing environmental nitrogen in soil and enabling farmers to cut back on artificial nitrogen fertiliser applications.
In NUE-Leg, Germinal Horizon will use DoubleRoot as the basis for producing future varieties with even stronger agronomic performance.
RedRunner – stoloniferous red clovers
Red clover (Trifolium pratense) is a high-protein, high-yielding legume highly suitable for UK farming systems. However, current varieties are intolerant of grazing, leading to persistence failure.
Germinal Horizon is developing novel stoloniferous red clovers with a similar growth habit to white clover. This means they are more grazing tolerant while maintaining the greenhouse gas (GHG) inhibiting potential of red clover due to the presence of an enzyme, polyphenol oxidase (PPO).
PPO inhibits protein breakdown and production of nitrogenous GHGs while increasing polyunsaturated fatty acids in meat and milk products. These will be developed into commercial varieties under the name RedRunner.
Lotus
From the Lotus genus, Birdsfoot trefoil (Lotus corniculatus L.) foliage contains condensed tannins that aren’t present in clover. These tannins inhibit methanogenesis in the rumen by up to 32% and provide protein protection, reducing nitrogenous GHG emissions. Tannins also prevent bloat in cattle and have an anthelmintic effect in sheep.
Available commercial varieties are low-yielding and lack persistence under grazing. Germinal Horizon has produced high-yielding pre-commercial lines with improved grazing tolerance.
Spaced plant nurseries of each species will be established to measure variation in quality traits and agronomic potential, with clonal copies taken for investigating variation for N-fixation potential (with WP3).
Trial plots will be established at Germinal Horizon trial sites at Aberystwyth and Wiltshire to quantify forage quality and composition of swards with different seeding rates, species combinations and management.