Soil Compaction Changes How Beneficial Fungi Affect Water Movement in Soil

Jenn Hoskins
30th May, 2024

Soil Compaction Changes How Beneficial Fungi Affect Water Movement in Soil

Image Source: Natural Science News, 2024

Key Findings

  • Researchers at the Institute of Botany of the Czech Academy of Sciences studied the impact of arbuscular mycorrhizal fungi (AMF) on soil water holding capacity (WHC)
  • They found that AMF can either decrease or increase the WHC of soil, depending on the level of substrate compaction
  • In compacted substrates, AMF might reduce WHC, while in less compacted substrates, AMF can enhance water retention by improving capillary movement
Arbuscular mycorrhizal fungi (AMF) are known to provide numerous nutritional benefits to their host plants, including enhanced water uptake. However, their impact on soil hydraulic properties has not been extensively studied. Recent research conducted by the Institute of Botany of the Czech Academy of Sciences[1] has revealed intriguing findings about the influence of AMF on the water holding capacity (WHC) of soil substrates. In a series of experiments involving dwarf tomato plants and the AMF species Rhizophagus irregularis 'PH5', researchers discovered contrasting effects on the WHC of a sand-zeolite-soil mixture. Initially, they observed that the presence of AMF slightly but significantly reduced the WHC of the substrate. However, in a subsequent experiment, the opposite effect was noted, with the mycorrhizal substrate retaining more water than the non-mycorrhizal substrate. To understand these conflicting results, the researchers hypothesized that substrate compaction might play a crucial role. They suggested that in compacted substrates, AMF might have no effect or even decrease the WHC. Conversely, in less compacted substrates, the hyphae of AMF can weave through the pores, enhancing the capillary movement of water and causing more water to remain in the pores after free water has drained. This phenomenon indicates that the physical structure of the substrate can significantly influence the hydraulic properties mediated by AMF. These findings build upon previous studies that have highlighted the role of AMF in plant water relations. For instance, AMF have been shown to enhance the soil's capability to transport water and extend the effective root length, thereby improving crop tolerance to drought[2]. Additionally, AMF colonization has been associated with increased root branching and changes in root morphology, which can further influence water uptake and retention[3]. The ability of AMF to transport water directly to host plants has also been demonstrated, with studies showing that AMF can account for a substantial portion of the water transpired by host plants[4]. The current study adds a new dimension to our understanding of AMF by suggesting that their influence on soil hydraulic properties is not straightforward and can vary depending on the physical characteristics of the substrate. This insight is crucial as it underscores the need for further research to elucidate the mechanisms by which AMF affect soil-water dynamics. In summary, the research conducted by the Institute of Botany of the Czech Academy of Sciences highlights the complex interplay between AMF and soil hydraulic properties. By showing that substrate compaction can alter the effects of AMF on WHC, this study opens new avenues for investigating how mycorrhizal fungi can be leveraged to improve soil water management in agricultural systems. Future research should focus on understanding the conditions under which AMF can enhance or diminish soil water retention, thereby providing valuable insights for optimizing crop performance in varying soil environments.

EnvironmentMycology

References

Main Study

1) Soil compaction reversed the effect of arbuscular mycorrhizal fungi on soil hydraulic properties.

Published 29th May, 2024

https://doi.org/10.1007/s00572-024-01153-9

Related Studies

2) The role of arbuscular mycorrhizal symbiosis in improving plant water status under drought.

https://doi.org/10.1093/jxb/erad249

3) Arbuscular mycorrhizal induced changes to plant growth and root system morphology in Prunus cerasifera.

Journal: Tree physiology, Issue: Vol 15, Issue 5, May 1995

4) Routes to roots: direct evidence of water transport by arbuscular mycorrhizal fungi to host plants.

https://doi.org/10.1111/nph.18281


Related Articles

An unhandled error has occurred. Reload 🗙