Pathogen incidence on tree and liana seedlings along a chronosequence of tropical forest recovery in Panama

To assess how pathogen incidence affects plant community assembly during tropical forest recovery, we recorded foliar fungal pathogen incidence on 6,010 seedlings (5-200 cm tall) of 176 tree and 71 liana species along a chronosequence of ten forest sites in Panama ranging in age from 9 to 129 years. We used this dataset to test the hypotheses that pathogen incidence (1) increases with forest successional age, (2) increases with local species seedling abundance, (3) is greater for liana than tree seedlings, and (4) varies with tree species’ life-history strategy.

Methods
Pathogen incidence was scored at the plant level by visual inspection. A plant was scored as infected with foliar pathogens if one or more of its leaves showed necrotic lesions, black or orange rust spots, auras around missing leaf area, and/or a white powdery surface.