Abstract

The fungus Neonectria fuckeliana has become an increasing problem on Norway spruce (Picea abies) in the Nordic countries during recent years. Canker wounds caused by the pathogen reduce timber quality and top-dieback is a problem for the Christmas tree industry. In this study, four inoculation trials were conducted to examine the ability of N. fuckeliana to cause disease on young Norway spruce plants and determine how different wound types would affect the occurrence and severity of the disease. Symptom development after 8-11 months was mainly mild and lesion lengths under bark were generally minor. However, N. fuckeliana could still be reisolated and/or molecularly detected. Slow disease development is in line with older studies describing N. fuckeliana as a weak pathogen. However, the results do not explain the serious increased damage by N. fuckeliana registered in Nordic forests and Christmas tree plantations. Potential management implications, such as shearing Christmas trees during periods of low inoculum pressure, cleaning secateurs between trees, and removal and burning of diseased branches and trees to avoid inoculum transfer and to keep disease pressure low, are based on experiments presented here and experiences with related pathogens.

Keywords

Picea abies; Nordic countries; canker; microconidia; inoculation; lesion length; infection

Published in

Forests
2018, Volume: 9, number: 3, article number: 105
Publisher: MDPI

SLU Authors

• Pettersson, Martin

  • Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
    

• Rönnberg, Jonas

  • Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network


UKÄ Subject classification

Forest Science


Publication identifier

DOI: https://doi.org/10.3390/f9030105

Permanent link to this page (URI)

https://res.slu.se/id/publ/95811