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Agriculture is a constant battle against the elements. Farmers need to worry about the weather, the soil, and pests that want to eat their crops before they can send them to market.
As farming has become a bigger business, focused on turning over huge crops, we’ve largely turned to monoculture. When a farm grows one kind of plant, it is more efficient from an economic standpoint, but also means that a single kind of insect can wipe that crop out. This creates a need to use pesticides that can harm other insects, as well as other animals that eat those insects.
According to a new study, there may be a way to fight back against insect pests while minimizing pesticide use: we need to end monoculture.
Farms that grow a variety of crops face fewer insect pests, because insects have very specific nutritional needs. A bug that lives on corn, for example, thrives when there are huge fields of the stuff. When there is a mixture of crops, they can’t thrive as much. This isn’t to say that they’ll never eat that corn, but they won’t be able to devastate it.
“A monoculture is like a buffet for plant-eating insects where every dish is delicious, said study lead author William Wetzel, a doctoral student at UC Davis. “A variable crop is like a buffet where every other dish is nasty.
For small farms, having a variety of crops is a huge help. But for giant farms, which benefit from the efficiency of monoculture, the problem is harder to solve.
The authors of the study suggest that such farms introduce a greater genetic variety within their plants.
Consumers tend to like consistency in their vegetables, so ears of monoculture corn, for example, have to look and taste as much alike as possible. But bugs don’t eat the ears of corn that we like. They want the leaves. Thus, if farmers can vary the genetics of the leaves while leaving the ears alone, the bugs may not do as much damage to the crop.
Genetic variation of leaves would allow for consistency in flavor and appearance in the edible parts while making crops’ genetic makeup more diverse.
This mixing of plants is already being done on wheat and rice fields to reduce disease, but so far it hasn’t reduced insects.
“But it shows that it’s possible to mix varieties and genotypes together,” says Wetzel. “Now we need to think about how to do that to control insects.”