Field-trials of a genetically modified plant which could provide an alternative source of omega-3 oils for the aquaculture industry have been given the go-ahead by the UK’s Department for Energy, Food and Rural Affairs (Defra).
Oily fish such as tuna and mackerel obtain omega-3 fatty acids through feeding on marine algae, and in turn pass them on to humans when eaten, delivering health benefits such as a reduced risk of coronary heart disease. Farmed fish are given fish oil in their feed to replicate the effects of the marine algae. Currently, around 80% of all the fish oil harvested from the sea is consumed by the aquaculture sector, according to the Food and Agriculture Organization.
Sources of oil-rich fish feed range from ‘feed-grade’ fish, which is unfit for direct human consumption, to fish-offal waste products – with some more sustainable than others. As the aquaculture industry grows (it already accounts for nearly 50% of all fish consumed globally) alternative sources of omega-3 oils might be needed to protect marine food chains.
Scientists from Rothamsted Research, the largest agricultural research centre in the UK, may have developed one such solution. The team successfully recreated the genes responsible for omega-3 oil synthesis in marine organisms, and inserted them into Camelina, an oilseed plant in the cabbage family. The plant has been shown to accumulate the desired oils within its seeds in lab settings. The new trial will investigate whether this also occurs in the field.
“We are delighted to be in position to carry out the field trial and to further assess the potential of these GM plants to contribute, as one of many solutions, to the important environmental sustainability issue of providing omega-3 fish oils”, said Professor Martin Parry, Acting Director of Rothamsted Research.
However, James Simpson of the Marine Stewardship Council believes it would be unwise to overestimate the plant’s potential. “It is very difficult to determine the current impact the harvesting of fish oils is having on marine ecosystems”, he says, “and therefore it would be impossible say if this terrestrial source of fish oils could impact positively on wild fish populations.”
The Camelina plants project is being funded through the Biotechnology & Biological Sciences Research Council, the largest public funder of non-medical bioscience in the UK. A small amount of the plants’ seeds will be analysed for their oil content over the course of four growing seasons, and the remainder of the seeds (and the rest of the plant material) will be destroyed under the conditions of the trial. – Patrick McKenna
Photo credit: Sarah Usher / Rohamsted Research