The relationship between pruning and the incidence of Neonectria fuckeliana in Pinus radiata

Abstract

Background: Nectria flute canker is an important disease of Pinus radiata in the South Island of New Zealand. The causal agent of the disease, Neonectria fuckeliana, is a known wound invader of Picea abies in Europe. To test the hypothesis that pruning wounds are necessary for infection of Pinus radiata by N. fuckeliana, the presence of the fungus was assessed in pruned and unpruned trees. Methods: The presence of the fungus was investigated in a total of 180 trees (90 pruned and 90 unpruned) using both DNA and microbial culturing techniques over three consecutive years. The data was analysed using a logistic regression analysis. Results: It was found that there was no significant difference in the presence of the fungus in pruned and unpruned trees. Conclusions: These results indicate that pruning wounds are not the primary infection court for N. fuckeliana and that the fungus is able to enter the tree through an alternative infection point. © 2013 Ramsfield et al.