Correlation between Wilting Index of Plant Morphology Defined by 2DFT Spectrum and Micro-environmental Factors

Wilting is one of life-features of plants responding to drought stress. Early identification of plant wilting is of importance for effective use of water in crop production. For this purpose, a laser scanner based on the principle of triangulation project was used to obtain 3D images of plants and the DC component of 2DFT was extracted as a wilting index. Four species, including zucchini, gourd, pumpkin and okra, were tested. The experimental results demonstrated that this index could identify the early wilting for each species and has a good linear correlation with the wilting degrees (R2 > 0.82). In addition, the statistical models of multiple linear regression, which relates the wilting index to DVPD and the solar effective radiation, was proposed; and it can be used as the qualitative index of plant water deficit stress degree.