These Mites Rain Down To Save Your Strawberries | Deep Look

From Deep Look.

Two tiny mites duke it out on strawberry plants throughout California. One is a spider mite that sucks the juices out of the delicious crop and destroys it. The other, persimilis, is a crafty predator that growers drop by the thousands from high-tech drones to protect their fields.

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Individual spider mites are barely visible, about the size of a grain of salt, but together they cause huge damage to crops around the world. They suck sap from the leaves and stems of crops and houseplants, leaving yellow or dry rusty leaves and tangles of fine silk.

Farmers can use pesticides to knock them back, but spider mites quickly develop resistance, making them particularly stubborn pests.

So many farmers turn to biological control agents. One of the most popular is another type of mite commonly called persimilis. This predatory mite hunts down spider mites and their eggs.

But spreading the tiny hunters over vast agricultural fields is a challenge, so some growers are turning to companies like Parabug to disperse the predators by air using drones.

Now, entomologist Christian Nansen and engineer Zhaodan Kong at UC Davis are looking at ways to automate this entire process of crop protection. They’re developing a strategy using drones armed with special cameras to detect changes in the way sunlight bounces off plants’ leaves.

Software using machine learning algorithms would then read the subtle changes in the leaves’ reflectance and come up with a diagnosis about what was causing the stress. If the system suspects a spider mite infestation it could then summon a second drone, packed with predatory mites. The team is working on developing software to accurately drop the predators right on the trouble areas.

“The idea is that these natural predators are like tiny paratroopers coming in on the drones,” said Nansen, “with a special eye in the sky that sees exactly where they need to go.”

— What are spider mites?
Spider mites are not insects. They’re arachnids, more closely related to spiders and ticks.

— How do I get rid of spider mites?
One of the best ways to get rid of spider mites on houseplants and garden crops is to spray the plant with water to knock the mites off. There are pesticides that will kill them, but spider mites have a knack for becoming resistant. Oils are also used to smother the mites. Biological control agents like predatory mites can be particularly effective.

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🏆Congratulations🏆 to these 5 fans on our Deep Look Community Tab for identifying the sharp mouthparts of the Persimilis mite – chelicerae!

Ivar Golubenko
Yann Cohen

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