A high quality low-cost digital microscope minirhizotron system

An easily reproducible system is presented for minirhizotron image acquisition based on a digital microscope and entirely built with low-cost components. The system weighs 2.28 kg, is connected to a portable computer through USB, and allows collection and storage of high-quality digital images without other components or power sources. Settings at 25 x magnification provide pixel sizes of 25 and 12 mu m respectively with a medium pixel density microscope (640 x 480 pixel), and a high pixel density microscope (1280 x 1024 pixel). This kind of system coupled with recent developments of robotics and automatic image analysis for minirhizotron frames allows to envisage fast, low-labour and low-cost root investigation methods with a high degree of automation. (C) 2011 Elsevier B.V. All rights reserved.