PhD network

Impacts of agronomic practices on wheat stem diseases

PhD student: Bela Fistric
Main supervisor: Jon West

​

Wheat is the primary arable crop produced in the United Kingdom and Denmark. One of the key threats to wheat crops are fungal pathogens which can account for 15-20% yield loss per annum. One crop protection strategy is the use of chemical fungicides however, fungicides are costly and can be detrimental to local wildlife and water systems. Another way to help mitigate these pathogens whilst using less fungicides is by adapting agronomic practices. The severity of stem pathogens such as Eyespot (Oculimacula sp) is affected by the agronomic practices used in the fields such as crop rotation or tillage but it unknown exactly how much of this control can be attributed to agronomy versus fungicide use. This project will be comparing farms in the UK and Denmark as both countries have very similar climates however, farmers in Denmark tend to use far lower fungicide doses (spending an average of £46.29 or 397.72DKK less per hectare).
This project aims to investigate stem pathogen phenotypes, use molecular profiling to precisely diagnose pathogens, and investigate the relationship between agronomic practices and pathogen prevalence. This research should help to inform best practice and widen our knowledge of wheat stem diseases.

​

​

Towards a mechanistic understanding of disease suppressive soils

PhD student: Kelis Fisher
Main supervisor: Tim Daniell

​

My focus is on what is happening in and around the soil to create the phenomena: disease suppressive soils. These have been found in many systems and are known to reduce crop disease, improving the reliability of yields. This project aims to investigate what might be causing the conditions that promote crop health, with the aim to adapt the mechanisms to allow for application and promotion of suppressive soils on farm land.

​

​

Using environmental DNA to assess soil health bioindicators and their relationship to crop nutrition and production under different

agricultural regimes.
 

PhD student: Sabina Schneider
Main supervisor: Penelope Watt

​

Healthy crops start with healthy soils. Yet the European Soil Observatory reports that up to 89% of agricultural soils show critical functional decline, a symptom of widespread soil degradation driven by intensive agriculture. Focusing on soil health as a critical pillar of the One Crop Health framework, this project monitors earthworms as bioindicators of soil health using eDNA metabarcoding, a high-throughput alternative to traditional sampling methods. Utilising both the One Crop Health farms network and field experiments, including Rothamsted’s Large Scale Rotation experiment and the University of Copenhagen’s CRUCIAL trial, we will investigate the effects of contrasting agricultural regimes on earthworm diversity and abundance. As ecosystem engineers, earthworms mediate soil processes including nutrient cycling, organic carbon sequestration, aggregate formation, and water infiltration. There is also growing evidence that earthworm activity is associated with yield benefits in agricultural
systems, particularly in low-nutrient soils. We will therefore also assess soil physicochemical properties, crop growth, yield, and nutrition via micronutrient analysis. We expect agricultural regimes that benefit soil biota and earthworms to show enhanced soil health functioning, with benefits to crop performance.

​

​

The impact of functional biodiversity in insect-weed interaction

PhD student: Caroline Bayer Frøhling
Main supervisor: Stine Kramer Jacobsen

​

Pesticides are commonly applied to suppress weeds and arthropods, but in doing so they also disrupt agroecological interactions that can enhance the natural defenses of both the crop system and individual plants. When managed strategically, weeds can function as beneficial components of the agroecosystem, contributing to the induction of resistance mechanisms in the main crop. By utilizing agroecological resilience in the cropping system, it is possible to reduce the need for pesticides, by strengthening ecological processes that regulate pest populations.
I have three different objectives, that explore different aspects of agroecological resilience:

1. Investigate induced resistance mechanisms to insect pests in cereal crops as a response to increased weed diversity.
2. Link functional diversity of weed and arthropod species communities, a trait-based approach correlating community responses to changes in weed diversity.
3. Assess arthropod predators’ utilization of weed resources by molecular analysis of predator feeding guilds.

Together, these objectives address agroecological resilience from the plant, community, and trophic-interaction perspectives. My research is a combination of greenhouse experiments, in-field sampling, chemical analysis, and molecular analysis.

​

​

Harnessing eDNA for surveillance and management of agro-biodiversity

PhD student: Zhao Li
Main supervisor: Natasha de Vere

​

My project, Harnessing eDNA for surveillance and management of crop health pests and beneficials in agroecosystems, focuses on testing how environmental DNA (eDNA) and DNA metabarcoding can be used to characterize aerial and terrestrial biodiversity in farmland ecosystems. My work investigates soil communities, including fungi, plants, arthropods, and microbes, and also uses eDNA collected from leaf surfaces to study aboveground biodiversity associated with crops. In addition, I identify pollen and fungal spores from air samples to better understand aerial biodiversity dynamics. These datasets are compared with existing records on pests, weeds, diseases, and beneficial organisms across the One Crop Health farm networks. My main contribution to the project is generating biodiversity data from Danish farms and contributing to the development of biodiversity indicators for agricultural systems. By combining molecular tools with ecological data, my work aims to improve our understanding of biodiversity patterns in farmland and explore

how these data can support practical and sustainable farm management.

​

​

Breaking the bank: Weed seed decay in arable soils

PhD student: Leon Bedekovic Arnaut
Main supervisor: Paul Neve

​

My PhD investigates how the soil microbiome regulates weed seed banks in agricultural systems and explores whether healthy soils can naturally suppress weed species. By applying the 'epidemiological triad' framework, my research examines how the interaction between the environment (agricultural management and climate), the host (seed identity), and the agent (soil microbiome) determines the rate of seed decay in an agroecosystem. Through a combination of field and glasshouse experiments, and microbiome characterisation across contrasting soil types and management intensities, I intend to identify the mechanisms driving seed decay. The research aims to determine whether manipulation of soil microbial communities can accelerate weed seed degradation and shift weed community dynamics. This work sits at the intersection of plant ecology, microbial ecology, and agroecology, addressing questions about the potential for developing weed-suppressive soils. By linking soil health to weed management, the project contributes to broader efforts in regenerative agriculture and reduced pesticide dependency.

​

​

Companion cropping to support weed-arthropod interactions, biodiversity

and ecosystem services in arable fields
 

PhD student: Suresh Banisetti
Main supervisors: Bo Melander and Claus Rasmussen

​

My research focuses on how companion cropping shapes plant diversity, weed communities, and arthropod populations, and how these interactions support ecosystem services such as natural pest control and pollination. Specifically, I study the use of legume companion crops to suppress weed growth while providing valuable resources for beneficial insects. I also examine the ecological role of weeds, particularly their importance as habitats and floral re-sources for arthropods that contribute to pest regulation. By exploring the synergies and trade-offs between biodiversity, weed suppression, and crop productivity, my research aims to develop more sustainable crop management systems. Ultimately, this project aims to reduce reliance on synthetic pesticides by developing nature-based strategies for pest and weed regulation to support productive, resilient, and biodiversity-friendly farming systems.

​

​

Mechanistic co-simulation of Insects, Weeds and Plant Infestation

in Agricultural Fields

 

PhD student: Eva Enevoldsen
Main supervisor: Sune Darkner

​

My project concerns mechanistic co-simulation of insect pests, weeds, and diseases. The idea is to simulate multiple crop threats at once to better map how the different threats interact and how they affect the crop, as part of finding ways to
minimise pesticide use on fields. The main crops to look at will be winter oilseed rape and winter wheat. In addition to exploring how a crop reacts to multiple crop threats at once, there will also be an exploration of how a field is infested which will likely be done using epidemiological modelling to model densities of different crop threats on the field. The simulations will mostly be done in APSIM. Additional simulation will be done in smaller simulators to test ideas in a simpler setting before simulating at a larger and more detailed scale in APSIM.

​

​

​

​