US Trials Give New Insights into Grass Breeding

Article excerpt

Byline: RICHARD HALLORAN

RECENT research trials in the United States, using conventional plant breeding techniques, are leading to new insights into how best to improve the nutritional value of forage grasses for dairy cows.

This work has been undertaken to facilitate the many American milk producers who have converted back to grazing-based production systems over the last couple of years.

And, with stocking rates of up to one cow per acre now becoming commonplace, the onus is now on scientists to come up with new grass types which will allow farmers to optimise production from the 'great outdoors'.

"We now know that developing forage varieties containing higher levels of soluble carbohydrate, or selecting for those in which the fibrous fraction has been de-coupled from the digestible components in the grass, represents the way forward," University of Wisconsin agronomist, Dr Michael Casler, told Farming Life.

However, the alternative approach of breeding for varieties with less fibre content has been shown to be fraught with difficulties as the end result can be grass types that are susceptible to disease, such as crown rot.

"To improve animal performance, researchers are likely to have greater success if they select for plants where the lignin is less tightly bound to cell walls or select for plants with more nutrients inside cells," stressed Dr Casler. …