Scientists at the University of York and the John Innes centre have identified genetic markers that could assist in identifying ash trees that are resistant to Ash Dieback.

Ash Dieback, is caused by the fungus Hymenoscyphus fraxineus (previously Chalara fraxinea) which often results in tree mortality. It is hoped that the research will lead to a test to find trees with a low susceptibility to the fungus which could then be used to replaced lost ash trees.

http://www.telegraph.co.uk/news/earth/environment/12098065/Ash-dieback-breakthrough-as-scientists-learn-to-spot-resistant-trees.html