Genome editing aims to increase diversity

The green revolution has reduced hunger in this world, but unfortunately it has also reduced biodiversity. Genome editing is now being used to breed new plants that require fewer pesticides or fertilizers. Agriculture is to become a creator instead of a destroyer.

Industrialized agriculture is one of the factors that significantly affects biodiversity on Earth. Over the last hundred years, the so-called green revolution has led to increases in productivity, but not without side effects. The use of synthetic chemical pesticides, advancing mechanization and the associated cultivation of monocultures or rainforest deforestation and the resulting land use changes are three major factors that have a negative impact on biodiversity.

The proponents of industrialized agriculture are now hoping that technological progress will turn the negative effects of agricultural practice into positive ones. New genetic engineering methods (genome editing) such as CRISPR/Cas9 are to be used to breed varieties that require fewer pesticides and are more efficient in their use of water and nutrients(Bayer, 2018). A rogue who thinks evil of it. The question arises as to what extent genome editing can preserve or promote the diversity of crop varieties on the one hand and biodiversity in general on the other?

Let's start with the diversity of cultivated species and varieties. Globally, there are over 350,000 plant species, of which over 50,000 are edible and around 7,000 are collected and cultivated. Only 30 species account for 95% of the food consumed globally, with rice, wheat and maize alone accounting for 60%.(ProSpecie Rara 2015) This impoverishment of crop species and varieties is also known as genetic erosion and is a result of industrialized agriculture. Through mechanization and increased efficiency, all those crops that do not fit into the current mechanization scheme have been "weeded out". It is doubtful that new breeding methods will bring about a return to this trend. This is because new varieties will only be developed if they can be marketed accordingly by the seed companies or if a corresponding market is available.

Most cultural species and varieties are the result of farming activity and their development is subject to a different logic. They arise from the logic of adaptation and exchange between neighbors and/or groups. In contrast to the classic high-performance varieties, which must be standardized and profitable (patented). Taking these aspects into account, it is therefore unlikely that the diversity of crop species and varieties can be improved by means of new genetic engineering.

But how can the relationship between genetic engineering and biodiversity be assessed in general? Can genetically modified varieties make a positive contribution to biodiversity?

If the proponents of new genetic engineering have their way, the answer to these questions is yes. A brochure published by an international agribusiness company claims that the use of genetically modified varieties would mean up to 37% less pesticides would have to be used, with up to 22% higher yields, of course. On the other hand, a study by the Federal Agency for Nature Conservation showed that the use of pesticides in herbicide-tolerant plants has actually increased over a period of 20 years and that there has been a significant decrease in biodiversity on arable land(Schütte et. al., 2014). This is mainly due to resistance that has developed in weeds and weeds over time. It may not yet be possible to make a conclusive assessment of this, but it would be possible to do completely without synthetic chemical pesticides anyway, as organic farming has been demonstrating very successfully for a long time.

Another important factor that influences biodiversity in agricultural ecosystems is the size of the field. Structural change is not only increasing the size of farms, but also the size of arable land. This may create advantages in terms of cultivation time, but it does not promote biodiversity. A study from 2008 came to the conclusion that the optimum field size is 1-2 ha; beyond this, machine efficiency increases only marginally.

However, the new genetic engineering serves precisely that system of industrialized agriculture that lives mechanization and increased efficiency as its highest credo. It is therefore very unlikely that new genetic engineering will make a positive contribution to biodiversity. By way of illustration, an analysis of satellite data for the sub-Andean region (Brazil & Argentina) came to the conclusion that 48% of all fields in this area are now larger than 50 hectares .

One thing is certain, biodiversity is under great pressure. Researchers are already talking about the sixth great mass extinction and agriculture is partly responsible for this. Technological progress alone will not be able to stop this.

Rather, a systemic rethink is needed, as demonstrated by organic farming, even if it faces major challenges (dependence on large seed companies and conventionalization trends such as larger fields - towards mechanization). And the external costs of food production must be quantified and charged to those who cause them. Ultimately, fair conditions in agriculture can only be ensured through cost transparency.

About the author

Florian Egger studied environmental and bioresource management and organic farming at the University of Natural Resources and Life Sciences with a research focus on soil processes. With this knowledge and his practical experience, he is committed to sustainable food production.