FIG 1.
Two-dimensional schematic representing mutational neighborhoods of φ6 P3. Circles represent P3 mutational neighborhoods of the mutants, which are the centers of circles. The geometric shapes are known P3 mutants. It is assumed that they are distributed on the mutational neighborhood (circles) in a nonrandom way. The arrows are events, such as host range expansion. PA, P. syringae pv. atrofaciens; PT, P. syringae pv. tomato.