FIGURE 2.

Attachment of A. tumefaciens strain C58 to tomato root hairs in a 1/10 dilution of MS medium containing a 1/20 dilution of AB minimal medium (A) and in 60 mM CaCl₂, 7 mM sodium acetate, and 247 mM mannitol pH 5.8 (B). Note the large decrease in attachment in the presence of the CaCl₂-containing medium Laterally attached bacteria are visible at the white arrows in (B); polarly attached bacteria are indicated by the black arrows. Approximately 10⁶ bacteria per ml were incubated with cut tomato roots for 24 h.