High sugar ryegrasses bred at IBERS have become a worldwide success story, renowned for their ability to improve livestock productivity while also reducing greenhouse gas emissions.

Development of these transformational perennial ryegrasses began back in the 1980s. Based on a detailed understanding of plant carbohydrate biochemistry and the breakdown of grasses in the rumen of sheep and cattle, the research led to a revolution in the selective breeding of forage grasses to improve their quality. Scientists found that when livestock lack readily available energy sources (e.g. from water soluble carbohydrates commonly known as “sugars”), productivity is lower and there are higher outputs of nitrogen in faeces and urine which is bad for the environment. By understanding carbohydrate biochemistry and how plant metabolites are broken down in the rumen of an animal’s stomach, plant breeders were able to identify genetic diversity in sugar accumulation in perennial ryegrass.

This breakthrough led to the development of grasses with a higher soluble carbohydrate concentration. These high-sugar grass varieties (such as AberDart and AberMagic) were rapidly taken up by industry. Their use benefits farmers and the environment, through an increase in ruminant agriculture productivity and a reduction in diffuse nitrogen pollution and greenhouse gas emissions. These high sugar grass varieties are sold by IBERS’ long-term commercial partners, Germinal, and are grown not only in the UK but also increasingly overseas.