Exploiting foliar yeasts for fungal pathogen inhibition and mycotoxin degradation

Exploiting foliar yeasts for fungal pathogen inhibition and mycotoxin degradation

Microbial Ecology

Contact Person:

Droevendaalsesteeg 10
6708 PB Wageningen

Suitable for Master students for at least six months.

Fusarium graminearum is a fungal foliar pathogen and the causal agent of Fusarium head blight (FHB), a devastating wheat disease that annually causes considerable economic losses, with yield losses up to 70%. This fungus produces a variety of mycotoxins, small low molecular weight compounds with a toxic effect on both food and feed. Multiple strategies have been employed to lower or prevent Fusarium growth through: i) fungicide application, ii) breeding for FHB-resistant cultivars, and iii) microbial inoculations. Fungicide application has proven to be effective in reducing FHB incidence, however, these chemicals are harmful to the environment and human and animal health, while breeding for resistant cultivars is time-consuming and pathogens quickly overcome the resistance. Therefore, the focus of this project is to explore the potential of foliar yeasts for novel microbiome-based approaches to protect plants from pathogen infections.       

Yeasts have proven to be able to suppress fungal growth (Figure 1) and absorb toxic compounds in their cell walls. Yeasts are adapted to harsh abiotic conditions, including toxic compounds such as fungicides and toxins. In this project, we will employ our previously established ‘Phyllosphere Yeast Repository’ (Gouka et al., 2022), an extensive collection of yeast isolates and genomes, to investigate their ability to protect wheat plants against F. graminearum infection. Additionally, we will track their colonization and abundance in planta through qPCR and microscopy and quantify the production of mycotoxins.

  • Figure 1. A. Different confrontation assays to investigate the possible antagonistic activity of phyllosphere yeast. B. SEM of interaction zone
  • Figure 2. Detached leaf assay for high-throughput in vivo screening
  • Goal: Determine the potential of yeasts to inhibit the fungal pathogen F. graminearum and degrade mycotoxins.
  • Techniques:  Different techniques in microbiology, molecular biology and analytical chemistry will be applied.
    Detached leaf assay (Figure 2), DNA and RNA isolation for (RT)-qPCR, (Fluorescent) microscopy and HPLC-UV for mycotoxin quantification.
  • Importance: Fusarium graminearum causes substantial economic and crop yield losses worldwide, especially in product quality due to contamination of food and feed with mycotoxins, threatening human and animal health.
  • Supervisors and location: Department of Microbial Ecology, Netherlands Institute of Ecology, Wageningen, The Netherlands

For further information and applications: MSc. Linda Gouka (daily supervisor L.Gouka@nioo.knaw.nl) and Dr. Viviane Cordovez (V.Cordovez@nioo.knaw.nl)


Relevant literature

Description of the ‘Phyllosphere Yeast Repository’ which will be used in this project:

Genetic, phenotypic and metabolic diversity of yeasts from wheat flag leaves. Gouka, L. et al., 2022. Frontiers in Plant Science

Example of different techniques that will also be used in this project:

Selection of fungal endophytes with biocontrol potential against Fusarium head blight in wheat. Rojas, Edward C. et al., 2020 Biological Control