Radial-growth and wood anatomical changes in Abies alba infected by Melampsorella caryophyllacearum: A dendroecological assessment of fungal damage

Abstract

The fungus Melampsorella caryophyllacearum causes serious damage on Abies alba. However, radial-growth loss caused by the fungal infection has not been quantified before. In the Spanish Pyrenees, three stands were sampled (dasometry, incidence, intensity), and cores were taken from asymptomatic and symptomatic trees for dendroecological analyses. Climate-growth correlations were assessed through correlation functions relating monthly mean temperature and total precipitation with radial growth. The incidence of the disease significantly increased with tree dominance. The maximum reduction of radial growth (20%) in symptomatic trees was observed during 1983-2002, when xylem showed frequent traumatic resin ducts. During the year before growth, the radial-growth loss was positively correlated to a wet December. In the year of tree-ring formation, growth loss was negatively correlated with minimum temperatures in February, March and April. The climatic effects on radial-growth of asymptomatic and symptomatic trees are discussed. © INRA, EDP Sciences, 2006.