In China, the US and Sweden, new methods of genetic engineering, such as CRISPR (so-called DNA-scissors) are being used to produce forest trees. Applications for field trials with genetically engineered poplars were filed in Sweden in 2016. The genome of these trees has been engineered to bring about a range of changes that affect flowering, growth, production of branches, leafs and roots. The goal of this type of engineering is to drastically change the phenotype and characteristics of the trees. Economic reasons for their development are, for example, faster growth or a change in the quality of wood for the paper industry.
What is the problem?
Forest trees have complex interactions with the environment, including with mycorrhizae, insects, different species of wildlife and other plants. Within their lifetime, poplar trees can produce millions of seeds and great quantities of pollen, which can be dispersed by the wind over many kilometres. Their artificial DNA can spread via pollen, seeds and shoots. The introgression of genetically engineered trees into native populations can have irreversible negative consequences for ecosystems, and there is no way of implementing reliable risk assessment because of the long term periods that would need to be assessed. In addition, the possible interactions are far too complex. Therefore, the cultivation of genetically engineered trees should not be allowed under conditions where they can propagate, spread into native populations or invade ecosystems.
There are reports that currently more than a million genetically engineered poplars producing an insecticide are growing in China, the first trees were introduced 25 years ago. Not all of the sites where the trees are grown are known. At the same time, there is hardly any investigation into spread, or impact on the environment. Genetically engineered trees have also been authorised for commercial release in the US and Brazil. These authorisations are for eucalyptus and pine trees. Currently, there is a lack of reliable information to which extent such trees are actually being grown.