FIG. 2.

Lesion formation by B728a and mutant derivatives on bean leaves. Bacterial suspensions were made from King's medium B plates grown for 2 days at 28°C. Bacteria were suspended in water and diluted to 10⁶ CFU per ml in 10 mM phosphate buffer (pH 7.2). Bacteria were infiltrated locally into the leaves of 14-day-old bean plants. The photograph was taken 3 days postinoculation using a Kodak DCS420 digital camera. The arrows indicate the pathogenic reaction caused by infiltration of B728a or BALG1. The small circular wounds within the area infiltrated by BGACΩ1 were caused by the infiltration process.