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With Disease Resistance Comes Insect Susceptibility12-27-16 | Education

With Disease Resistance Comes Insect Susceptibility

U.K. University Study on Ash Trees

Threats to the health of ash trees include ash dieback and the emerald ash borer. New research from the University of Exeter and the University of Warwick indicate that resistance to one of these threats creates greater susceptibility to the other.

Ash dieback is a fungal disease of ash trees that has spread throughout Europe, with the first suspected cases reported in Poland in 1992. Spores can be transmitted by wind, leading to rapid spread of the disease. Ash dieback, in conjunction with the emerald ash borer, has the potential to be devastating to ash trees.

Researchers at the University of Exeter and the University of Warwick studied the chemical composition of ash trees that were resistant or susceptible to ash dieback, and found that resistant trees have fewer defenses against insects that prey on ash trees.

In other words, selecting trees for their fungal resistance could put them at risk from emerald ash borer, which was found in Moscow in 2003 and has since spread west through Europe, reaching as far as Sweden.

The research is part of a study involving several universities and government institutes that looked at the DNA of ash trees to identify ash dieback resistance. The Exeter and Warwick scientists looked at chemical composition instead.

"Our findings underline the need for further research to ensure that we select ash trees resilient to present and future threats," said study co-author Professor Murray Grant of the University of Warwick.