Nocturnal Fungi: Airborne Spores in the Canopy and Understory of a Tropical Rain Forest1

ABSTRACT Pathogens and other symbiotic fungi that infect above‐ground plant parts commonly disperse as airborne spores. Here we present diel patterns of the density of airborne fungal spores in the canopy and understory of a tropical rain forest. Spores were 52‐fold more abundant in the understory than in the canopy. Additionally, spores were 5‐ to 35‐fold more abundant at night than during the day, associated with environmental conditions conducive to germination and plant infection.