Field measurements of airborne concentration and deposition rate of maize pollen

In recent years there has been interest in the dispersal of maize ( Zea mays) pollen from crops, particularly in relation to gene flow and seed quality. We report the results of experiments that measured maize pollen dispersal from a 20 m×20 m experimental crop. The experiments were done in a commercial farm in France during the summer of 2000. Pollen production was estimated to range from 10 4 to 2×10 6 grains per day per plant. Pollen concentrations and deposition rates decreased rapidly with distance from the crop: concentrations decreased by about a factor of 3 between 3 and 10 m downwind of the source; deposition rates at 30 m were