Plant Exudates Improve the Mechanical Conditions for Root Penetration Through Compacted Soils
Overview
Authors
Affiliations
Background And Aim: Plant exudates greatly affect the physical behaviour of soil, but measurements of the impact of exudates on compression characteristics are missing. Our aim is to provide these data and explore how plant exudates may enhance the restructuring of compacted soils following cycles of wetting and drying.
Methods: Two soils were amended with Chia ( seed exudate at 5 concentrations, compacted in cores to 200 kPa stress (equivalent to tractor stress), equilibrated to -50 kPa matric potential, and then compacted to 600 kPa (equivalent to axial root stress) followed by 3 cycles of wetting and drying and recompression to 600 kPa at -50 kPa matric potential. Penetration resistance (PR), compression index (C) and pore characteristics were measured at various steps.
Results: PR decreased and C increased with increasing exudate concentration. At 600 kPa compression, 1.85 mg exudate g soil increased C from 0.37 to 0.43 for sandy loam soil and from 0.50 to 0.54 for clay loam soil. After 3 wetting-drying cycles the clay loam was more resillient than the sandy loam soil, with resilience increasing with greater exudate concentration. Root growth modelled on PR data suggested plant exudates significantly eased root elongation in soil.
Conclusion: Plant exudates improve compression characteristics of soils, easing penetration and enhancing recovery of root induced soil compaction.
The primacy of temporal dynamics in driving spatial self-organization of soil iron redox patterns.
Dong X, Richter D, Thompson A, Wang J Proc Natl Acad Sci U S A. 2023; 120(51):e2313487120.
PMID: 38096416 PMC: 10742380. DOI: 10.1073/pnas.2313487120.
Uncovering root compaction response mechanisms: new insights and opportunities.
Pandey B, Bennett M J Exp Bot. 2023; 75(2):578-583.
PMID: 37950742 PMC: 10773992. DOI: 10.1093/jxb/erad389.
Tapping into Plant-Microbiome Interactions through the Lens of Multi-Omics Techniques.
Mishra A, Sudalaimuthuasari N, Hazzouri K, Saeed E, Shah I, Amiri K Cells. 2022; 11(20).
PMID: 36291121 PMC: 9600287. DOI: 10.3390/cells11203254.
Root exudate composition reflects drought severity gradient in blue grama (Bouteloua gracilis).
Ulrich D, Clendinen C, Alongi F, Mueller R, Chu R, Toyoda J Sci Rep. 2022; 12(1):12581.
PMID: 35869127 PMC: 9307599. DOI: 10.1038/s41598-022-16408-8.
A glass bead semi-hydroponic system for intact maize root exudate analysis and phenotyping.
Lopez-Guerrero M, Wang P, Phares F, Schachtman D, Alvarez S, van Dijk K Plant Methods. 2022; 18(1):25.
PMID: 35246193 PMC: 8897885. DOI: 10.1186/s13007-022-00856-4.