CANYON When disease and insect problems in crops are visible to the naked eye, it may be too late to treat. Thats why Dr. Christian Nansen, Texas AgriLife Research entomologist, likes to take a closer look.
A hyperspectral look, that is.
Nansen, small grains entomologist at the Texas AgriLife Research and Extension Center at Lubbock, uses a hyperspectral camera to determine how light is being reflected off plant leaf surfaces. He discussed the technology at the High Plains Vegetable Conference in Canyon.
Just like when we start having the flu, our body responds and we get a fever, he said. The fever is because our body is mobilizing its immune system. When a plant undergoes stress caused by diseases, insects or the environment (like drought), it will cause changes in its metabolism and that leads to subtle changes in the way it reflects light.
We can use this camera to detect stress at an earlier stage than by visual inspection.
For instance, Nansen said, root rot is all underground, and generally plants are half dead when the damage becomes visible.
But if you could see it earlier, you may have time to treat for the fungus causing the problem, he said.
The hyperspectral camera detects diseases in any plant, Nansen said. And with insect damage, the key parameter to control is early detection.
When scouting for spider mite infestation, you have to take a lot of samples to see mites when the infestation level is low, he said. But with spectral imaging, you can see it earlier and it is less intrusive.
The technology is similar to that of remote sensing, Nansen said. However, instead of putting the camera in an airplane, it is placed just over the canopy of a crop, perhaps mounted on a four-wheeled all-terrain vehicle or on the center-pivot irrigation system.
He said his research team is in the early stages of testing the technology. They are starting by collecting spectral
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Texas A&M University - Agricultural Communications