White clover may reduce methane emissions
29 Jun, 2010
A new type of white clover that is high in tannins could help reduce methane emissions and help to combat climate change, as well as increase the health of animals such as cows or sheep.
This is due to a discovery by New Zealand research scientists at AgResearch.
Scientists at the research centre Grasslanz Technology believe the key is to develop white clover that contains higher concentrations of condensed tannins in their leaves. Tannins are the chemical compounds that make plants like tea or red grapes dark in colour.
Condensed tannins are a complex group of chemical compounds that are able to bind to protein and protect it from breakdown in the stomachs of sheep or cattle. These tannins only exist in higher levels in white clover and are entirely absent in grasses.
AgResearch scientists believe they can improve white clover by modifying it (to give grazing animals a higher intake of protein) while at the same time reducing methane emissions. In addition, the genetic breakthrough could improve animal health and reduce nitrogen waste. These are important issues for sustainable farming and would help combat climate change.
Another benefit may be reducing bloat in animals eating clover-rich pastures. Bloat is caused by too much gas building in their stomachs that can lead to the death of the animal. This is common particularly in spring when pasture growth is rapid and animals eat a lot more.
Currently, white clover contains extremely low levels of tannins, found only in the flowers. If AgResearch scientists can alter this to allow condensed tannins to accumulate to effective levels in leaves, there will be major benefits.
It is an exciting breakthrough but is still at the research stage. There is a long way to go until it is available for farmers to use.
- 30 June 2010