Vertical and horizontal dispersion of conidia of Stenocarpella macrospora and Stenocarpella maydis

Experiments were carried out in the field to quantify airborne dispersal of Stenocarpella maydis and S. macrospora conidia from naturally infected corn (Zea mays) straw. The data indicated that 93% and 88% of the total number of sampled conidia of S. maydis and S. macrospora, respectively, were trapped during the day, differing statistically from the night period. The number of sampled conidia of both fungi, was inversely proportional to the vertical and horizontal distance of spore traps from the inoculum source. Conidia were collected up to a height of 2.0 m and up to 120.0 m from the inoculum source. In both experiments, the frequency and the number of collected spores were the highest at a height of 25.0 cm and at a distance of 20.0 m from the inoculum source. Conidia was dispersed in the air as individual spores and/or grouped in cirri and not essentially associated to rain splashes.

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