Adaptive Minirhizotron for Pepper Roots Observation and Its Installation Based on Root System Architecture Traits

In this study, researchers developed an adaptive minirhizotron, reduced to a microrhizotron (1.1 × 1.1 × 1.2 cm), to non-destructively observe and measure root traits of pepper plants (Capsicum annuum). They reconstructed the root system architecture using a three-dimensional caliper to determine optimal installation patterns. The best performance in root interception was achieved with a horizontal angle of 45°, a radius of 30 mm, and a vertical angle of 45°, showing a 96.7% interception probability. The microrhizotron effectively observed fine roots as small as 0.1 mm in diameter, with relative errors of 12.1% in root length and 15.4% in root diameter compared to soil sampling. This tool can be used for various research applications, including quantitative trait locus analysis and studying root hair growth.