Root growth of maize as studied with minirhizotrons and monolith methods

Abstract

The root minirhizotron technique (MT) has been used to monitor nondestructively the root growth of field crops. The objective of this study was to compare the ability of MT to measure the root length density (RLD) of maize (Zea mays L.) as compared to the quadrate monolith method (QMM). The experiment was conducted at the Gucheng Ecological-Meteorological Experiment Station in China during the summer of 2007. RLD was estimated using MT and QMM. Results showed that the vertical distribution of RLD decreased top-down gradually, starting at the top of the root zone. The growth rate of RLD decreased as soil depth increased based on both methods. RLD was underestimated by MT at depths between 0 and 40 cm at the milk and maturity stages and overestimated by MT at depths between 0 and 20 cm at the jointing and tasseling stages. There was a significant correlation (r 2 = 0.715, α = 0.05) between RLD estimates based on QMM and MT. The results of this study indicate that properly calibrated MT is a reliable method to screen nondestructively the root growth of maize.

Rainfed maize root morphology in response to plant population under no‐tillage

“…Quantification of maize and wheat ( Triticum aestivum L.) root morphology in response to agronomic practices using the CI‐600 In Situ Root Imager has been successfully performed in the past (Munoz‐Romero, Benítez‐Vega, López‐Bellido, & López‐Bellido, 2010; Sindt, 2017) and were deemed a reliable method to investigate maize root growth by Liao et al. (2015). The digital images were analyzed using the RootSnap!…”

Relating Profile Wall Root-Length Density Estimates to Monolith Root-Length Density Measurements of Cover Crops

“…Root-length density (RLD) of cover crops is frequently assessed in crop studies due to its high relevance for crop functions such as nitrogen uptake from deep soil layers [1][2][3][4][5], erosion control [6] and crop productivity [7]. Different quantitative methods have been employed to measure RLD in the field, of which soil core sampling [4,5,[8][9][10][11][12], field installation of minirhizotrons [1][2][3]9,[13][14][15] and soil monolith (MO) extraction [8,9,16,17] are the most frequently used. These methods are considered to be either very time consuming and/or expensive, but believed to be the most accurate in representing real values [8,18,19].…”