Biotech News


U.S. Testing Begins on Genetically Modified Ryegrass Developed in New Zealand

Jun 5, 2017

Genetically modified ryegrass developed to reduce methane emissions and nitrate discharges by livestock is being tested in the United States, reports NZ Farmer.

Limits on GM experimentation in New Zealand have resulted in several ryegrass varieties developed by scientists from AgResearch being sent offshore for further testing.  Scientists hope the U.S. trials will verify the results of lab work and modelling carried out here which found the grasses could reduce methane emissions, cut pasture costs and increase production on New Zealand dairy farms.

The five-year field and animal nutrition trial program is a joint project with DairyNZ and will test up to four high metabolizable energy ryegrass lines.  The last two years will include animal nutrition and greenhouse gas emissions testing on animals in containment.

Speaking at DairyNZ's Farmers' Forum in Stratford, AgResearch senior scientist Kim Richardson said the forages contained a GM technology that improved photosynthesis by as much as 20 percent, leading to 50 percent higher plant growth rates.

"These plants also contain higher levels of lipids in the leaf - about seven per cent where a non-GM variety has about 3.5 per cent," Richardson said.  "That increases metabolizable energy by about 10 percent and improves the overall nutritional value of the plant."

Lipid content in ryegrass was more seasonal than in GM varieties and two genes had been modified to make the lipids stable in the leaf, he said.

"Initially we modified one gene to boost lipids and it worked but within three or four weeks it was back down. Modifying another gene meant we were able to stabilize lipid levels."

For every 1 percent increase in lipids, a 5 percent decrease in methane could be expected, meaning an overall reduction of up to 23 percent, Richardson said.

"GM crop trials in New Zealand are limited to the greenhouse and these results will have to be verified by animal field trials but that's what we're hoping to achieve though the U.S. program."

A recent grant from the Ministry of Business, Innovation and Employment's Endeavour Fund, along with funding from AgResearch, DairyNZ and other stakeholders, meant an investment of $25 million over five years into the genetically modified forages research.

Source: NZ Farmer