A simple method for two-dimensional color analyses of plant leaves.
Coloration and color pattern are basic information for plant physiology, ecology, and taxonomy. Until recently, such color analysis of biological materials required expensive equipment. Here we report a convenient method for analyzing color of plant leaves with ImageJ, free software. Color digital images of croton leaves were divided with ImageJ into Red, Green, and Blue images, and then exported as two-dimensional numeric data. After processing images with Adobe Photoshop Elements and Microsoft Excel, color patterns were obtained as histograms. A comparison of the histograms evaluated characteristics of croton leaf variegation. The method successfully quantified color information of the plant leaves with an inexpensive PC set. Apart from taxonomic applications, the simple algorithms allow application of the present methodology to various types of color and color pattern analyses.