Are we creating a ‘super weed’, and how scared should we be of herbicide resistance?

Roundup is the most common herbicide, but will it work for much longer?

Weeds cost the U.S economy a whopping 30 billion dollars a year by competing for our crop’s nutrients, but are in a constant and gruelling fight for survival with herbicides. These herbicides kill the weeds, increasing yields by a third. The fear is that weeds will become resistant, creating ‘super weeds’, and with three billion more people to feed in thirty years, will be a serious threat to food security. But how likely is this, and should we be worried?

Well, herbicide resistance is happening, all the time in fact. By slightly altering the shape of their proteins, weeds can avoid the toxic herbicide, and if the genes for that protein spreads into the next growing season, will compete with the crop for nutrients and reduce yields.

The response of farmers is simple: rotate the different kinds of herbicides and the weeds won’t be able to react in time. However, Dr Christophe Delye is concerned that herbicide rotation might work in the short term, but could promote long-term resistance to not one but all herbicide types.

Farmers often rotate their herbicides to kill weeds like these ones.

He explains that herbicides work by targeting a specific part of a weed, say, the amino acids. Until recently, we thought that the response of the weed was equally specific, altering just the targeted amino acid. The reality however, is that when stressed, the weeds exhibit a range of responses, on multiple parts of multiple genes and in doing so, gaining a slight resistance to all herbicides.

Keep doing this and eventually the ‘super weed’ will be able to avoid every toxic herbicide we throw at them.

So should we be worried? Although the chances of a dystopian and barren landscape in 50 years is unlikely, we already have so many worries in the food system (see links below), that reduced yields from herbicide resistance simply cannot be allowed.

Is the choice between agriculture and biodiversity really an ultimatum? https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/139

Multi-billion pound American companies deliberately cause famine in Malawi to increase their profits. https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/87
The Soil we Live on is Disappearing and it is YOUR Responsibility. https://wordpress.com/block-editor/post/swiftscience971095579.wordpress.com/55

Is the choice between agriculture and biodiversity really an ultimatum?

A once diverse community is converted into a sea of golden wheat.

Land that used to harbour an array of life is being converted into vast expanses of tumbling golden carpets of wheat fields, relentlessly smothering and suffocating everything in its path. This planting of monocultures is considered the single biggest threat to biodiversity on Earth. However, nearly a billion people are malnourished, and with an extra 2 billion more people by 2050, we have to find more food from somewhere.

It may seem like an ultimatum between food or forests, but Dr Joern Fischer from The Ecological Society of America examines how food can be produced without human’s mass slaughter of anything living.

Fischer suggests that combining fields and forests by having fallow years, targeting areas for native wildlife to establish, or even just to have a row of trees at the boundary of the farm is enough to significantly increase biodiversity. Providing a lush oasis in the middle of the rolling dunes in wheat field deserts would not only save vital species, but make the crops less vulnerable to disease or shocks and stabilize and pump nutrients into the soil, ultimately increasing yields in the long term.

In Costa Rica, they have combined agriculture and natural forests to create a diverse, but productive landscape.

Fischer also notes the importance of creating corridors between ‘natural paradises’ or national parks. Every creature has a certain climate they thrive in, called their ‘climate envelope,’ outside of which survival is a struggle. Clearly, a polar bear would struggle in the Amazon and Trump (or Drumpf, which is his original family name) would struggle in any meaningful conversation. These natural refuges can’t move and so, with climate change, more and more species are suffering in a climate their not supposed to be in. Natural corridors would offer a network, like roads between cities, for creatures and trees to travel across in order to stay within their envelope.

It seems then that whilst intensification of agriculture is needed to feed the world, we can work with nature to produce more food, whilst maintaining oases for wildlife to thrive.