Dispersal of Erwinia carotovora subsp. atroseptica in splash droplets

Water drops, diameter 4 mm, fell 13 mm onto suspensions of cells ofErwinia carotovora subsp.atroseptica containing Mg (ANS) dye. The resulting splash droplets were collected on ohotographic film, on Petri plates containing pectate agar or on fresh potato slices. Fewer droplets produced craters in the pectate than were detected on the film by fluorescence of the dye. Slices did not rot at some distances and with some bacterial concentrations, although craters developed in adjacent pectate plates suggesting that fewer bacteria could produce a crater than were needed to initiate a rot in a slice. The proportion of droplets producing craters increased as the concentration of bacteria increased from 102 to 108 cells ml1. In still air, droplets and craters were not detected beyond ca. 125 cm from the point o