Inoculum density of <i>Verticillium dahliae</i> from point sampling.

<p>Histogram (A) and spatial pattern (B) of estimated inoculum density (CFU g^-1 of soil) of <i>Verticillium dahliae</i> in three commercial cotton fields (W_A, W_B, and W_C) using a real-time quantitative PCR method. Within each row, 35 soil samples (at depth 0–20cm) were taken; the circle size is proportional to the CFU estimate at the point (the largest circle corresponds to 300 CFU g^-1 of soil in W_C).