The AgResearch developed High Metabolisable Energy (HME) ryegrass had proved in the laboratory to reduce methane and nitrous oxide emissions and nitrogen leaching while improving productivity but the NZ-funded, five-year trial to test those claims was likely to be done in the US.
AgResearch Grasslands principal plant biotechnology scientist Greg Bryan said difficulties navigating NZ’s Hazardous Substances and New Organisms Act, likely restrictions on further research and co-funder sensitivity with overseas markets meant it was easier to do the trials offshore.
The Ministry for Business, Innovation and Employment and seed companies had provided $10 million for the trials but AgResearch had applied to US regulators for permission for the field work.
Information and data would be gathered from the US trials and used to decide if an application would be made to do further field trials in NZ, which could take a further three years.
“If we get to that point, we would be repeating some of the work but also expanding it under NZ conditions.”
Should HME pass the field trials, it was possible funders could decide regulatory conditions in NZ prevented the cultivar’s release here and it would be marketed overseas.
Ongoing testing of HME under laboratory conditions confirmed earlier findings that it improved productivity while also addressing environmental issues such as nitrogen leaching and reduced methane and nitrous oxide emissions.
But whether HME would be a feature of the NZ farmscape was a decision NZ had to make and not an outcome he or the industry could predict, Bryan said.
Depending on the variety, HME showed in the lab it grew 30-60% faster than conventional ryegrass cultivars, produced 10% more metabolisable energy, reduced methane emissions by 15-20% and nitrogen in urine by 9%, which meant less leaching and emissions of nitrous oxide.
“We’re pretty excited by the potential it can provide farmers with the environmental side of it and at the same time not compromising productivity.”
Bryan said their confidence in HME was boosted by the recent field trial performance of soya beans, which used similar genetic modification technology as HME.
That technology increased photosynthesis in soya beans by 10%, which meant a 10% increase in seed numbers, with the seed 7% heavier from plants that were 12% higher.
The HME trials would be done by US contractors who would first visit NZ to learn about ryegrass. NZ scientists would regularly visit the field trials to observe.
The first year of the trial would confirm techniques and systems, plant performance and develop plant material, with hundreds of individual plants grown and monitored.
In years two and three the trial would expand and comparisons between different lines of HME would be made with testing for laboratory assumptions and performance, such as a lower need for nitrogen fertiliser and a greater drought tolerance.
Nutrition trials would follow in years four and five with HME grass cut and taken to stock housed in chambers so greenhouse gas emissions could be monitored and other measurements taken.
A 10% increase in metabolisable energy was measured in the laboratory along with milksolids gains of 12-17%, assumptions that would also be tested.
Bryan said despite the competition for limited research funds, AgResearch received strong Government and industry support, including from DairyNZ and seed companies.
“Here is an opportunity for NZ farmers to have a tool to manage their environmental impact and at the same time not compromise productivity but increase farm efficiency and may even reduce the amount of bought-in feed as they will be able to grow more feed onfarm.
“The opportunity for farmers and the environment is quite significant,” Bryan said.
