Different Algorithms for Detection of Malondialdehyde Content in Eggplant Leaves Stressed by Grey Mold Based on Hyperspectral Imaging Technique

Abstract

The feasibility of using hyperspectral imaging (HSI) technique to measure malondialdehyde (MDA) content in eggplant leaves stressed by grey mold was evaluated in this paper. Hyperspectral images of infected and healthy eggplant leaves were obtained in the spectral region of 380 to 1030 nm, and their spectral reflectance of region of interest (ROI) was extracted by Environment for Visualizing Images (ENVI 4.7) software. Several pre-processing methods were adopted and partial least squares (PLS) models were established to estimate MDA content in eggplant leaves. In order to reduce high dimensionality of spectral data, competitive adaptive re-weighted sampling (CARS) and latent variables (LV) were carried out to identify the most effective wavebands. The result showed that PLS model based on baseline pre-processing had a good performance for prediction set. On the basis of the effective wavelengths suggested by CARS and LV, PLS and multiple linear regression (MLR) models were established, respectively. Among...