A mesocosm‐based assessment of whether root hairs affect soil erosion by simulated rainfall

Abstract

Although plant canopies are widely recognized to protect the soil and help mitigate soil erosion, recent research has shown that the majority of soil scour prevention can be attributed to the roots. Because roots are more difficult and time‐consuming to measure than shoots, research in this area has largely been limited to understanding the influence of large roots and/or whole root systems, and there is little understanding on how smaller root traits, such as root hairs, contribute to the root system's ability to mitigate soil erosion. Therefore, this study subjected a root hairless mutant (brb) of barley (Hordeum vulgare L. cv. Pallas) and its wild‐type (WT) genotype to simulated rainfall. The results showed that increasing root presence significantly reduced soil erosion, but the impact of root hairs was less clear. Soil detachment significantly decreased as root length density increased, with no apparent genotypic difference in this relationship. The brb root systems produced significantly thinner (0.8‐fold) roots and a higher percentage (1.1‐fold) of fine roots, with both traits previously associated with increased ability to mitigate soil erosion. However, brb mesocosms produced a similar quantity of eroded soil to WT mesocosms, suggesting that root hairs in WT plants could have compensated for their root systems' reduced ability to mitigate soil erosion.Highlights It is not known whether root hairs affect a root system's ability to mitigate soil erosion. Soil yield following simulated rainfall was compared for a root hairless mutant (brb) and its WT. Root traits of brb favoured erosion mitigation, but brb and WT mesocosms eroded to the same degree.

Building soil sustainability from root–soil interface traits

“…However, it is less clear if they result in meaningful impacts in the field. Even in a laboratory study, hairless root mutants of Hordeum vulgare had a similar capacity to stabilise soil against erosion as their wildtype parent, but root system architecture confounded interpretation [68]. As in this work, many other studies have used hairless mutants to disentangle mechanisms, but meaningful data for crop breeders needs to contrast commercially viable varieties with differing root hairs and rhizodeposition [69].…”

Characterization of root traits for phosphorus deficiency tolerance using chromosome segment substitution lines

“…The root surface area was calculated using the following equation: 1, 0.1-0.2, 0.2-0.5, 0.5-1.0, and >1 where RSA is the root surface area and D i and RL i are the mean diameters (0.05, 0.15, 0.35, 0.75, and 1.5 mm) and root length of the five diameter classes, respectively. RSA is the sum of root surface area of five diameter classes under the assumption that the root is cylindrical (Burak et al (2020).…”

“…and Kato (2011and Kato ( , 2013. The root surface area was calculated us 166 following equationBurak et al (2020): is the root surface area and Di and RLi are the mean diameters (0.05, 0.1 170 0.75, and 1.5 mm) and root length of the five diameter classes, respectively. RSA is 171 of root surface area of five diameter classes under the assumption that the root is cy172 173 Root anatomical trait measurements 174 In Exp2, hand cross-sections were observed to estimate root anatomical structures.…”

Responses of soil microbial metabolic limitations to erosion under contrasting soil types and management practices

“…Hence, it should have the ability to regulate the negative effects of erosion on soil microbial processes. On the contrary, crops in agricultural land could diminish soil erosion by reducing the kinetic energy of raindrops through canopy and litter components, and root fixation can also prevent soil erosion and may offset the effects of erosion on soil microbial processes (Burak et al, 2021; Tamta et al, 2023). Additionally, the erosion processes and their effects on soil nutrients varied significantly with soil types.…”