The topic of the PhD project is: ‘Environmental fate of double stranded ribonucleic acid (dsRNA) plant-incorporated protectants from genetically modified crops’.
Pest control in agriculture heavily relies on the use of crops that are genetically modified to express insecticidal plant-incorporated protectants. The next generation of such genetically modified crops is currently coming to the market: RNAi crops. These produce double-stranded RNA (dsRNA) biopesticides that target specific insect pests feeding on the crops by a cellular regulation process called RNA interference. The use of RNAi crops will result in the release of dsRNA molecules to agricultural soils and surrounding water bodies. The environmental fate of these dsRNA molecules remains poorly studied and understood. Yet, fate information is urgently needed for ecological risk assessment of dsRNA biopesticides. The overall goal of this project is to investigate processes that govern dsRNA environmental fate in agricultural soils.
The PhD project aims at overcoming existing knowledge deficits on the fate of dsRNA molecules in agricultural soils by systematically investigating two major fate processes: sorption of dsRNA molecules to mineral and organic soil particle surfaces and the abiotic and biotic transformation of dsRNA molecules in soils. The focus will be on laboratory experiments carried out under well-controlled conditions to identify (i) the major interactions governing dsRNA adsorption and (ii) the reaction mechanisms involved in dsRNA transformation. The project aims at advancing our mechanistic understanding of dsRNA fate in soils, and will improve our ability to assess the long-term stability and fate of dsRNA molecules in soils.
The PhD student will have access to state-of-the art experimental systems and analytical techniques. The PhD student will further gain experience in developing new methods to characterize the fate of emerging biopesticides in environmental systems. In addition, the student will develop expertise in the underlying principles and concepts that determine the behavior of biomacromolecules in soils. Beyond these immediate outcomes, the PhD project is expected to advance our general understanding of the fate of genetic material in the environment. The project is part of a larger research focus within the Environmental Chemistry group at ETHZ on the fate of biomacromolecules (including proteins, viruses, polymers and genetic material) in natural Systems.