title: Substantial heritable variation for susceptibility toDothistroma septosporumwithin populations of native British Scots pine (Pinus sylvestris).
abstract: The threat from pests and pathogens to native and commercially planted forest trees is unprecedented and expected to increase under climate change. The degree to which forests respond to threats from pathogens depends on their adaptive capacity, which is determined largely by genetically controlled variation in susceptibility of the individual trees within them and the heritability and evolvability of this trait. The most significant current threat to the economically and ecologically important species Scots pine (Pinus sylvestris) is dothistroma needle blight (DNB), caused by the foliar pathogenDothistroma septosporum. A progeny-population trial of 4-year-old Scots pine trees, comprising six populations from native Caledonian pinewoods each with three to five families in seven blocks, was artificially inoculated using a single isolate ofD. septosporum. Susceptibility toD. septosporum, assessed as the percentage of non-green needles, was measured regularly over a period of 61 days following inoculation, during which plants were maintained in conditions ideal for DNB development (warm; high humidity; high leaf wetness). There were significant differences in susceptibility toD. septosporumamong families indicating that variation in this trait is heritable, with high estimates of narrow-sense heritability (0.38-0.75) and evolvability (genetic coefficient of variation, 23.47). It is concluded that native Scots pine populations contain sufficient genetic diversity to evolve lower susceptibility toD. septosporumthrough natural selection in response to increased prevalence of this pathogen.
authors: Centre for Ecology and Hydrology Bush Estate Penicuik Midlothian EH26 0QB UK.
authors: A
authors: A
authors: Perry
authors: Centre for Ecology and Hydrology Bush Estate Penicuik Midlothian EH26 0QB UK; Institute of Dendrology Polish Academy of Sciences Parkowa 562-035 Kórnik Poland.
authors: W
authors: W
authors: Wachowiak
authors: Forestry Commission 231 Corstorphine Road EH12 7AT UK.
authors: A V
authors: AV
authors: Brown
authors: Institute of Evolutionary Biology The University of Edinburgh Ashworth Building Charlotte Auerbach Road, King's Buildings Edinburgh EH9 3JF UK.
authors: R A
authors: RA
authors: Ennos
authors: Forest Research Northern Research Station Roslin Midlothian EH25 9SY UK.
authors: J E
authors: JE
authors: Cottrell
authors: Centre for Ecology and Hydrology Bush Estate Penicuik Midlothian EH26 0QB UK.
authors: S
authors: S
authors: Cavers
keywords: Dothistroma septosporum; Scots pine; adaptation; evolvability; heritability; susceptibility