The Executive Board of Wageningen University & Research has appointed Geert Smant as full professor and chairholder of Nematology at the Plant Sciences Group. He is the successor of Prof. Jaap Bakker, who held this position since 1998. The change already applies as per 1 March 2020.
After studying Plant Pathology in Wageningen (cum laude), Geert Smant focused in his PhD research on salivary proteins of potato cyst nematodes. These microscopically small roundworms are the soil-dwelling causal agents of disease in various Solanaceous plants. He completed his PhD research in 1998 under supervision of Prof. Bakker.
Geert Smant is fascinated by the success of nematodes as one of most species-rich groups within the animal kingdom. Although genetically diverse, most nematode species are morphologically hard to distinguish. However, remarkable differences are sometimes observed – particularly in parasitic nematodes - in the shape of the oral cavity and associated salivary glands. These special adaptations in the salivary glands provide a strong incentive to focus the research on parasitic nematodes on proteins secreted by these minute organs.
How nematodes penetrate host plant by secreting saliva
Over the years, the research of Geert Smant has contributed to several breakthroughs in the field of nematology, mostly related to the origin, complexity and functions of saliva of plant parasitic nematodes. For instance, salivary proteins are involved in the degradation of plant cell walls during host invasion by plant parasitic nematodes. The nematode genes encoding these plant cell wall modifying proteins have a striking similarity with homologs in soil bacteria. It is therefore thought that horizontal gene transfer from bacteria to nematodes has played a significant role in the evolution plant parasitic nematodes.
More recently it has become clear that salivary proteins of plant parasitic nematodes are also required for remodelling vascular tissue of host plants into permanent feeding structures. These permanent feeding structures enable nematodes, whilst being inside a plant for several weeks, to selectively extract assimilates from neighbouring plant cells. The salivary proteins contribute to the establishment and maintenance of the permanent feeding site by suppressing local host autoimmune responses.
For future research and education of the chair group Nematology, Geert Smant will particularly focus on setting up and further intensifying collaborations with groups having complementary expertise, such as soil ecology, medical and veterinary parasitology, and plant developmental biology.