ASK most people to list the causes of climate change, and you would expect to hear about oil companies, flights and cars. But, increasingly, we are realising that producing our food has massive environmental impacts. Farming is one of the main drivers of deforestation and global warming, among many other issues.
The flip side of this is that improving the way we farm can have massive environmental benefits. Boosting yields so that we can grow the same amount of food on half the land could save a forest, along with all the carbon that it stores.
Advertisement
One of the best ways to do this is to develop better breeds. The plants and animals we eat have already been transformed by conventional breeding, but it is a slow and clumsy process. Now we have a much more powerful and precise tool: CRISPR gene editing (see 鈥�Feng Zhang聽Q&A: CRISPR pioneer on the exciting future of gene editing鈥�).
Gene editing can be used in two ways. One is to quickly introduce desirable gene variants that already exist in other plants and animals. For instance, some beef cattle have very light coats due to a tiny change in one pigmentation gene. This same tiny change has been edited into dairy cows in New Zealand, with the aim of making them more heat tolerant in a warmer world.
鈥淪ome CRISPR creations could have undesirable consequences, but these should be judged on a case-by-case basis鈥�
Gene editing could also be used to make more extensive changes. For instance, many groups are trying to give extra crops the ability to fix nitrogen, just as peas and beans can. Such crops would need much less fertiliser, reducing emissions of the potent greenhouse gas nitrous oxide.
Another idea is to create crops with deeper roots that release suberin, a rot-resistant molecule found in cork. The idea is to lock away more carbon in the soil to help slow global warming.
Of course, some CRISPR creations could have undesirable consequences, as with any kind of breeding. But these should be judged on a case-by-case basis, because we also have to consider the risks of not embracing CRISPR crops and cows.
It is going to be very hard to reduce the greenhouse gas emissions from farming. Rejecting genetic technologies will make that job even harder.
