Marijke Steenackers is biologist specialized in breeding and diseases of forest trees. She started in 1983 at the Institute with research on resistance breeding of tree species such as poplar (Populus sp.), willow (Salix sp.), Wild cherry (Prunus avium) and common ash (Fraxinus excelsior). Since 2007 she lis leading the poplar breeding programme to bring new poplar cultivars on the market for the wood production in Europe. She's also responsible for the marketing of the poplar cultivars. 

For several years she is also researching the resistance of common ash to ash dieback (Hymenoscyphus fraxineus) with the view to bringing disease tolerant ash trees onto the market.