Project

Genetics and evolution of toxin production by Aspergillus flavus

Mycotoxin contamination in maize and other important crops like groundnuts is a major problem in Zambia, throughout Africa and beyond. Maize is often infested by mixed communities of fungi and unfortunately some of these fungi produce so-called mycotoxins. Our main objective therefore is to reduce mycotoxin contamination of maize through effective use of biological agents that promote replacement of producer by non-toxin producer strains.

Background

Central is the conceptual framework of niche exclusion that can occur in mixed communities of multiple species. In natural systems species co-exist and evolve as complex communities which is determined by the niche environment and the biological properties of each species. We will use theoretical models that use the ecological relationships between individuals and species to formulate predictions for the dynamics of mixed fungal maize-infesting communities.

Aim

These predictions will then be used to, firstly test their significance in describing inter-species dynamics and long-term stability of eco-systems. For the identified niches in maize, we will map how biotic and abiotic factors shape species interactions and stability of fungal communities. Secondly, we will design ways to destabilise these communities favouring non-toxigenic strains over toxigenic strains and will test methods for practical implementation to protect maize and other staple foods.

Approach

We will use the conceptual framework of niche theory and competitive exclusion to formulate experimental predictions for our species dynamics in mixed fungal communities. Firstly, we will elucidate what fungal toxigenic and non-toxigenic species are present and map how biotic and abiotic factors shape species interactions and community stability of fungal communities. Secondly, we will design ways to destabilise these communities such that non-toxigenic fungal strains are favoured over toxigenic strains. Finally, we will test methods for practical implementation to protect maize and other staple foods.

Student opportunities

We are open to applications for thesis projects! We have different thesis topics available, including projects with Field Work and/or Molecular Work. Are you interested? Contact Sijmen.Schoustra@wur.nl.