Leaf water content is one of the most important indicators of the plant growth status. However, the traditional measurement of leaf water content requires a destructive process. A new technique using near infrared (NIR) imaging with the aid of chemometrics was developed to predict leaf water content. This method makes it possible to evaluate the leaf water content without destruction. Ligustrum japonicum leaves were taken, and then the water content and spectroscopic images at the wavelength of 1450 nm were obtained by a vidicon camera fitted with a band-pass filter. A calibration model able to predict water content with high accuracy was found by partial least square analysis, using cumulative histograms based on the luminance brightness as the explanatory variables. This research confirmed the feasibility of NIR chemometric imaging to monitor the plant growth condition.
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