A NEW REPORT “buries the myth” that genetically modified oilseed rape or sugar beet pose any new problems for farming or the environment, according to the Agricultural Biotechnology Council.
GM crops tolerant of glyphosate or glufosinate total herbicides offer growers cheaper more flexible weed control with no apparent environmental downsides, the four-year rotational BRIGHT study suggests.
The project, begun in 1998, explored in detail the impact of growing GM herbicide-tolerant oilseed rape and sugar beet in rotations with cereals at five sites in England and Scotland.
For comparison the trials in the DEFRA/SEERAD-backed work were grown alongside rotations of conventional crops given the same management except for total herbicide applications. “BRIGHT illustrates that the flexibility allowed by GM crops will ensure that they can and will be grown in a manner that benefits the environment and farmers’ bottom line,” says ABC deputy chairman Tony Combes.
The study found no big differences in the populations of plants on land sown with GM and non-GM crops, notes BRIGHT scientific co-ordinator Jeremy Sweet.
Weed seed rise
No herbicide, conventional or otherwise, achieved 100% weed control in oilseed rape or sugar beet. Indeed the numbers of weed seeds in the soil had risen by the end of the project with little apparent difference between treatments.
“Any emergence of the herbicide-tolerant crops in subsequent rotational crops was easily controlled by the use of other herbicides,” says Mr Sweet. However there is no means of removing GM OSR volunteers from subsequent conventional OSR crops, he admits.
The herbicides for the GM crops could be applied later than conventional treatments and still control large weeds, the project confirmed.
This can leave more plant material available for insects and other organisms in the food chain, explains Mr Sweet.