A look into the genetic diversity of Lecanosticta acicola in northern Europe

Abstract

For northern Europe Lecanosticta acicola is an emerging pine needle pathogen. This study gives a first look into the population genetics of the pathogen in Estonia, the first population documented in that region. The main aim of this study was to investigate the genetic diversity and population structure of the pathogen in this new region for the fungus. For this purpose, 104 isolates from 2010 to 2017 were analysed with 11 microsatellite and mating type markers. The stand where the pathogen's jump from an exotic host to the native Scots pine was recorded was also involved in this analysis. The analysis revealed low genetic diversity and a high number of clones that indicated L. acicola is an invasive species in northern Europe. Results suggest that several separate introductions have taken place and anthropogenic activity has apparently affected the spread of the pathogen. Clonal reproduction is dominating and although sexual reproduction is possible, it probably takes place infrequently.

Keywords: Brown spot needle blight; Estonia; Invasive species; Mycosphaerella dearnessii; Population genetics.