Population structure and diversity of two pine needle pathogens in Colombia

Abstract

Planting Pinus species has contributed significantly to plantation forestry worldwide. Although mostly native to the Northern Hemisphere, pines have become established in most Southern Hemisphere countries due to their adaptability to almost all climatic conditions and various soil types. Their introduction into countries beyond their native habitats has inadvertently led to the anthropogenic introduction of pathogens into these non-native ranges. This dissertation focuses on two pine needle pathogens present in the Colombian pine plantations, namely Lecanosticta pharomachri and Dothistroma septosporum. A set of microsatellite and mating type markers was developed for Lecanosticta pharomachri and used to screen 120 isolates. The population genetics structure and diversity were then investigated. Existing microsatellite and mating type markers for Dothistroma septosporum were utilised in the investigation of the population structure and diversity of the pathogen which is now infecting trees which were previously thought to be tolerant to the disease.