GreenspectIR: revealing "hidden" plant spectral signatures

 

Multispectral imaging can be used in agriculture to uncover information about plant health before visible symptoms appears.

Like every object, plants reflect a part of the light that they receive from the sun. Depending on factors such as diseases, pests or stress levels, the plants are reflecting the light in specific ways. By looking beyond the visible spectrum, the GreenspectIR can measure variations of the light reflected and use it to detect signals of plant stress or diseases before they are visible to the human eye.

Vegetation indices

By comparing the light reflected by a plant at different wavelengths, multispectral imaging can be used to build vegetation indices such as NDVI or EVI. These indices focus on plant vigor, or in other words on how “green” a plant really is. A stressed plant will turn less green. But in the early stage of stress these differences in greenness are hard to detect with the human eye. Yet, being aware of these early signals are vital in crop management and provide farmers with “hidden” information on stress levels in the field, allowing them to take early actions.

Chlorophyll levels

However, plant stress level is not always a clear indicator of plant health. That is why we are also using multispectral imaging to build chlorophyll maps. The GreenspectIR is looking at specific wavelengths that are different from those used to build vegetation indices in order to reveal additional information on plant health. With this information farmers can detect signs of diseases earlier.

Here you can see how much information « hidden » in the RGB image is revealed when you look at an EVI image and at a chlorophyll map:

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Do you want to learn more about how GreenspectIR can assist your crop protection efforts? Contact us here or at info@polariks.com.

 
Polariks