Diplodia sapinea in Swedish forest nurseries

Diplodia sapinea is a common forest pathogen on Pinus spp. in a large part of the world. In 2013, disease caused by this pathogen on Scots pine (Pinus sylvestris) trees in Sweden was reported for the first time. In this study, we report the first detection of D. sapinea on diseased seedlings of P. sylvestris from two Swedish forest nurseries. Infected seedlings were collected July-November 2019. Diplodia sapinea was identified by morphological characteristics of fungal structures on plant tissues and from culture grown on Hagem agar media, followed by sequencing of fungal ITS rDNA. The result emphasizes the susceptibility of P. sylvestris seedlings. More research is needed to better understand the risk for disease spreading within forest nurseries and into the forest through infected plant material.