Pieter Pelser is a Lecturer in Plant Systematics and the director of the herbarium at the University of Canterbury in Christchurch, New Zealand. One research interest is the evolutionary history of the tribe Senecioneae, one of the largest tribes in the largest family of flowering plants.[1] He wrote the most recent attempt to define and delimit this tribe and its problematic founding species Senecio.[2] He also studies insects that eat these plants (Longitarsus) which contain pyrrolizidine alkaloids and what makes them choose which plants they eat.[3]
Another research interest is the Philippine members of the genus Rafflesia, which has the biggest flowers of any plant, and in particular the conservation of them.[1]