GM or non-GM; it’s the trait silly!20th September 2016
A basis of the registration process for GM crops is that they have no additional negative impacts on the environment than conventionally bred crops that have the same trait. Hence, it is hardly surprising that a recently published report from the Belgian plant science institute VIB concludes that:
Crop cultivation is by definition unnatural, and produces a negative impact on the environment. Plant breeding makes it possible to develop plants that reduce this impact. The impact, whether positive or negative, depends on the crop trait and the cultivation method, but not on the breeding technology used.
It is comforting that the registration systems for GM are working and that there have been environmental benefits. Over the last 18 years GM crops have worldwide saved 6.3 billion litres of fuel and 21.3 million kg on insecticide active substances. The report also highlights that when fields with insect-resistant GM crops are compared with conventional fields where insecticides are used, many more beneficial insects can be found in the fields with insect-resistant GM crops. Even opponents of GM agree that insect resistance can lead to more insect diversity in crops but I assume that they still object to using GM to achieve it. Surely by now they must suspect that they may be wrong in their unsubstantiated objections to this technology. However, they and (in some cases) their bank balances have nailed their colours to the mast and would find it impossible to backtrack.
The report does include a warning about the adoption of herbicide-tolerant crops. The continual use of a single mode of action to control weeds, particularly where minimum- or zero-tillage is adopted, is the strategy with the highest risk of developing herbicide resistance in weeds. I do worry that the easy route provided by GM herbicide tolerance could mean that European farmers might adopt these practices, despite the precedent set by US farmers that has resulted in glyphosate resistant weeds. Hence, the report emphasises that:
‘To prevent resistance in weeds, insects, and fungi, there must be integrated pest management, which involves using several means or techniques simultaneously against a particular pest.’
The report also contains some intriguing data on the role of plant breeding in feeding the world now and in the future. A group of economists has estimated the impact of removing the gains in cereal productivity attributed to the widespread adoption of improved varieties. They conclude that in 2004, between 18 and 27 million additional hectares of agricultural land would have been in use compared to 1965. Of this figure, an estimated 12 to 18 million hectares of land was spared in developing countries and 2 million hectares of deforestation prevented. There is no doubt that, as a result of widespread adoption of improved crop germplasm, increases in cereal yields have saved natural ecosystems from being converted to agriculture. It is a pity that the green blob does not yet ‘get’ the wider environmental benefits associated with agricultural technologies.