Skip to main content Skip to navigation

Dr Simon Jeffery

Supervisor Details

Simon is a soil microbial ecologist by training with a PhD in this subject area from Cranfield University in Bedfordshire. His main interests are in ecosystem functioning and in particular how soil organisms drive processes and functions across a range of scales from local to global. His work has been focused on understanding such processes with the aim of harness them to the benefit of us all in terms of increasing the productivity and sustainability of our use of soils.

Research Groups

EcoInsect Research Project


Project Details

Dr Jeffery is the primary supervisor on the below project:

The impact of regenerative agriculture on mechanisms underlying above-belowground interactions

Secondary Supervisor(s): Dr Joe Roberts, Dr Tom Pope 

University of Registration: Harper Adams University

BBSRC Research Themes: Sustainable Agriculture and Food (Plant and Crop Science), Understanding the Rules of Life (Plant Science, Soil Science)

Apply here!

Deadline: 4 January, 2024

Project Outline

It has become increasingly clear that conventional agricultural production systems negatively impact environmental health. Greater awareness of this issue has led to increased uptake in alternative crop production methods. Conservation agriculture is one such approach that aims to increase agricultural sustainability by treating soil as a living component of an ecosystem and working with soil biota to utilise the ecosystem services that they provide. Interest in this approach to crop production has increased in recent years. Alongside increased interest in regenerative agriculture, there has been an attitude shift regarding the interconnectedness of above-belowground interactions. It is widely accepted that aboveground and belowground interactions cannot be considered in isolation from one another, with changes in either one impacting the wider ecological network. Given that conservation agriculture aims to manipulate belowground interactions, there are likely to be consequences for aboveground interactions using this approach. Increasing our understanding of abode-belowground interactions has the potential to improve the sustainability of agriculture while concurrently minimising its negative impacts on the environment (Orrell and Bennett, 2013).

Arbuscular mycorrhizal (AM) fungi are a key group of soil biota for many arable crops, which act to augment plant health and resilience through increased provision of soil nutrients and water (Ceballos et al., 2013). These organisms are more prolific in conservation agricultural production systems due to its ethos of minimising soil disturbance. While belowground interactions between AM fungi and plants are well understood, their interactions with aboveground plant traits, particularly the fungus-plant-insect nexus, are comparatively understudied. Evidence indicates that belowground organisms such as AM fungi can enhance aboveground herbivore pest control in a range of crops (Schausberger et al., 2012). Pest control by belowground organisms is achieved through several routes: (1) plant defence priming, (2) priority effects and (3) volatile signalling to recruit natural enemies. Belowground organisms also act on other beneficial plant-insect interactions as AM fungi have been shown to enhance pollination by modifying floral traits (e.g., flower number and size) that increase pollinator visitation rates (Gange and Smith, 2005). Although the impact of belowground organisms on aboveground plant traits is well-documented, there has been limited field-scale research carried out in UK arable crops.

This project will quantify plant-AM fungi interactions in an ongoing conservation versus conventional agriculture field experiment and investigate how these belowground interactions influence both positive (e.g., pollination, pest control) and negative (e.g., herbivore feeding) aboveground interactions. Focus will be on determining how AM fungi influence chemically mediated plant-insect interactions.

References

Ceballos et al., 2013. The in vitro mass-produced model mycorrhizal fungus, Rhizophagus irregularis, significantly increases yields of the globally important food security crop cassava. PLoS One8, e70633.

Gange and Smith, 2005. Arbuscular mycorrhizal fungi influence visitation rates of pollinating insects. Ecological Entomology30, p.600-606.

Orrell, and Bennett, 2013. How can we exploit above–belowground interactions to assist in addressing the challenges of food security? Frontiers in plant science4, p.432.

Schausberger et al. 2012. Mycorrhiza changes plant volatiles to attract spider mite enemies. Functional Ecology26, p.441-449.

Techniques

  • Investigations of soil health by application of biomarkers and soil physicochemical analysis
  • Staining and microscopy to investigate mycorrhizal fungal root colonisation
  • Air entrainments to collect volatile organic compounds from organic material
  • Gas chromatography-mass spectrometry to identify volatile organic compounds
  • Insect assays to determine behavioural responses to a variety of stimuli

Dr Jeffery is also the co-supervisor on a project with Dr Marie Kirby.