Colony morphology and virulence of Vd<i>Δnoxb</i> and Vd<i>Δpls1</i>.

<p><b>A.</b> Colony morphology of wild-type V592, Vd<i>Δnoxb</i> and Vd<i>Δpls1</i> mutant strains, and Vd<i>Δnoxb</i>/<i>VdNoxB</i> and Vd<i>Δpls1</i>/<i>VdPls1</i> complemented strains on PDA plates after 2 weeks post-incubation. Both mutants show rapid growth and dramatically reduced melanin production, and complemented strains restore to the wild-type morphology. <b>B.</b> Disease symptoms of cotton plants infected with V592, mutant and complemented strains at 30 days post-incubation (dpi). The incidence of disease was evaluated with three replicates of 36 plants, and standard deviations are indicated by the error bars. <b>C.</b> Stem sections from inoculated cotton plants on PDA plates. Each section was from a different plant.