Some results of dynamic modelling for the dust tail formation of comet C/2006 P1 (McNaught) are presented. The clear transversal striae in its tail are characteristic features of the comet during observations near the perihelion. This phenomenon can be explained by the presence of local active areas on the surface of the rotating nucleus. The striated features are due to different dust production rate depending on whether the active areas are located on the sunlit or shaded side of the rotating nucleus. The tail of comet C/2006 P1 (McNaught) was fitted under the assumption that not only the dust flows uniformly from the nucleus, but also the considerable fraction of the dust streams out from three active local sources. Our model experiments give the period of comet C/2006 P1 (McNaught) to be 21 hours.