Effects of DC3000 inoculation time on disease development. (A) Photographs were taken 6 days after DC3000 inoculation. (B) Bacterial populations were measured at 1 hour and 3 days post-inoculation (OD = 0.1). The data represent mean values (± SD) of colony forming units (CFU) per square centimeter from five biological replicates, each replicate consisting of three leaf discs. Means denoted by the same letter did not significantly differ at p < 0.05 according to Duncan’s multiple range test. Initial bacterial numbers (1hpi) was quantified to ensure the uniformity of inoculation of DC3000. Black and white boxes correspond to dark and light periods, respectively, during a normal growth chamber day. The experiment was repeated twice with similar results.